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Background: In addition to the integrity of the meniscal hoop function, both the anterior and posterior meniscus roots as well as the meniscotibial and meniscofemoral ligaments are crucial in restraining meniscal extrusion. However, the interaction and load sharing between the roots and these peripheral attachments (PAs) are not known. Purposes: To investigate the influence of an insufficiency of the PAs on the forces acting on a posterior medial meniscus root repair (PMMRR) in both neutral and varus alignment and to explore whether meniscal centralization reduces these forces. Study Design: Controlled laboratory study. Methods: In 8 fresh-frozen human cadaveric knees, an arthroscopic transosseous root repair (step 1) was performed after sectioning the posterior root of the medial meniscus. The pull-out suture was connected to a load cell to allow measurement of the forces acting on the root repair. A medial closing-wedge distal femoral osteotomy was performed to change the mechanical axis from neutral to 5° of varus alignment. The meniscus was completely released from its PAs (step 2), followed by transosseous arthroscopic centralization (step 3). Each step was tested in both neutral and varus alignment. The specimens were subjected to nondestructive dynamic varus loading under axial compression of 300 N in 0°, 15°, 30°, 45°, and 60° flexion. The changes in force acting on the PMMRR were statistically analyzed using a mixed linear model. Results: Axial loading in neutral alignment led to an increase of the force of root repair of 3.1 ± 3.1 N (in 0° flexion) to 6.3 ± 4.4 N (in 60° flexion). In varus alignment, forces increased significantly from 30° (3.5 N; 95% CI, 1.1-5.8 N; P =.01) to 60° (7.1 N; 95% CI, 2.7-11.5 N; P =.007) flexion, in comparison with neutral alignment. Cutting of the PAs in neutral alignment led to a significant increase of root repair forces in all flexion angles, from 7.0 N (95% CI, 1.0-13.0 N; P =.02) to 9.1 N (95% CI, 4.1-14.1 N; P =.003), in comparison with the intact state. Varus alignment significantly increased the forces in the cut states from 4.8 N (95% CI, 1.0-8.5 N; P =.02) to 11.1 N (95% CI, 4.2-18.0 N; P =.006) from 30° to 60° flexion, in comparison with the neutral alignment. Arthroscopic centralization led to restoration of the native forces in both neutral and varus alignment, with no significant differences between the centralized and intact states. Conclusion: An insufficiency of the PAs of the medial meniscus, as well as varus alignment, led to increased forces acting on a PMMRR. These forces were reduced via an arthroscopic meniscal centralization. Clinical Relevance: Performing arthroscopic meniscal centralization concomitantly with PMMRR may reduce failure of the repair by reducing the load of the root. [ABSTRACT FROM AUTHOR]

Background: Discoid lateral meniscus (DLM) is the most common congenital abnormality of the meniscus. Tears are common; treatment is frequently not definitive, often requiring reoperation. Purpose: To report the clinical manifestations, physical characteristics, operative treatments and findings, complications, and reoperations of DLM in pediatric patients from multiple centers across North America. Study Design: Case series; Level of evidence, 4. Methods: Consecutive patients who underwent treatment for symptomatic DLM at 9 institutions between 2000 and 2020 were included. Patient data, presenting symptoms and signs, surgical findings, treatments rendered, and postoperative complications, including reoperation rates, were collected. Means with ranges and counts with proportions are reported for continuous and categorical variables, respectively, and comparisons were made using either the chi-square or Fisher exact test. Results: In total, 784 patients (867 knees) were included with a mean age at diagnosis of 12 years (range, 1-22 years) and a mean follow-up of 22.6 months (range, 0-154 months). Common preoperative symptoms were locking (33%) and snapping (30%). At surgery, tears in the DLM were present in 647 knees (594 patients [76%]); 95 knees (11%) had multiple tears; and in 140 knees, tears extended into >1 zone. Tears, when present, were more common within the posterior horn (41%) or body (34%) than the anterior horn (25%). Peripheral rim instability was reported in 241 knees (28%). Significantly more knees had instability posteriorly (15%; P =.0004) and anteriorly (9%; P =.0013) than along the body (3%). Tear type was most commonly complex (38%) or horizontal (34%). A total of 358 knees in 333 patients with tears (42% of all patients) underwent repair (55% of knees with tears). A total of 175 complications were reported, occurring in 139 knees in 134 patients (17%); 116 of these knees with complications (83%) had a single complication, while 23 (17%) had >1. Of the 784 patients, 105 (13%) underwent reoperation, undergoing 135 additional procedures related to their DLM. Of those, 60 (44%) were repeat arthroscopy and meniscal trim; 40 (30%), arthroscopy and meniscal repair; and 17 (13%), an articular cartilage procedure. Conclusion: Locking and snapping were common presenting symptoms. Over three-quarters of patients had meniscal tears, which were most often complex and located posteriorly. Seventeen percent of patients experienced complications, and a sixth of patients with complications had >1. Reoperation was typically for persistent symptoms or meniscal retear. [ABSTRACT FROM AUTHOR]

Background: Few studies have compared the characteristics of meniscal allograft tears between medial and lateral meniscal allograft transplantation (MAT) using bone fixation. Purpose: To investigate the prevalence, location, and patterns of allograft tears after MAT with the bone fixation technique and compare tear patterns between medial and lateral compartments according to the time elapsed after surgery. Study Design: Cohort study; Level of evidence, 3. Methods: The charts of consecutive patients who underwent primary medial or lateral MAT between December 1996 and June 2019 were retrospectively reviewed. The location, pattern, and postoperative periods during which allograft tears occurred were evaluated by reviewing all series of follow-up magnetic resonance imaging (MRI) scans, which were performed at 6 weeks, 3 months, 6 months, and 1 year postoperatively and every 2 years thereafter with the patient's agreement. Postoperative periods for allograft tears were defined as the time between surgery and the follow-up MRI scan in which the meniscal tear was first confirmed. Allograft tears were compared between the medial and lateral MAT groups. Results: A total of 327 consecutive patients who underwent MAT (55 medial, 272 lateral) with a minimum 2-year follow-up were retrospectively reviewed. The incidences of allograft tears after medial and lateral MATs were 32.7% and 30.9%, respectively. The mean times for tears were 80.1 ± 81.1 months and 48.9 ± 46.3 months in the medial and lateral MAT groups, respectively (P =.130). In both the medial and lateral MAT groups, allograft tears were observed mainly in the posterior horn, with complex tears being the most commonly identified tear type. In medial MATs, root tears were the second most common at 27.8%, with a significantly higher proportion than the lateral MATs (P =.014). On the other hand, in lateral MATs, meniscocapsular separation and radial tears were the second most common at 15.5% each, albeit not significantly more common than in medial MATs (P =.123 and P =.454, respectively). All root tears in medial MATs and meniscocapsular separations in lateral MATs were observed within 1 year postoperatively. Conclusion: Significant differences in allograft tear patterns were identified between the medial and lateral MAT groups. The proportion of root tears in medial MATs was higher than that in lateral MATs; conversely, the proportion of meniscocapsular separation was more common in lateral MATs. Such tear patterns, which may require surgical repair or graft resection, were observed only within 1 year of surgery. Therefore, close observation and regular follow-up in the earlier postoperative period are necessary after medial or lateral MATs. [ABSTRACT FROM AUTHOR]

Aims: Currently, it is advised to perform meniscal repair instead of meniscectomy in certain cases of primary anterior cruciate ligament reconstruction (ACLR). However, the level of evidence is low. Therefore, this study aimed to compare the effectiveness of meniscectomy and meniscus repair in addition to ACLR. Methods: The systematic search was conducted in three online databases (EMBASE, MEDLINE, and Cochrane) from inception until October 2021 for the literature on primary ACLR and concomitant meniscal surgery. Eligible studies compared the following outcomes between meniscal repair and meniscectomy groups: the Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm score, International Knee Documentation Committee (IKDC) score, and KT-arthrometer examinations. Lastly, we calculated pooled mean differences (MDs) with 95 % confidence intervals (CIs) from the change between pre- and post-intervention values. Results: Of 10,565 studies, 22 met the inclusion criteria, with a follow-up between 6 and 43 months. We found no difference when comparing the KOOS subscale changes—only in the KOOS pain subscale (MD = −1.6; CI: −2.48, −0.72). However, these results were not clinically significant. We analyzed the lateral and media meniscal injuries separately and concluded the same results regarding KOOS changes. We found no significant differences in the Lysholm score change (MD = −2.61; CI: −5.51, 0.29), changes in IKDC score (MD = 1.08; CI: −4.05, 6.21) or the change for the KT-arthrometer side-to-side difference (MD = −0.50; CI: −1.06, 0.06). Conclusion: Based on our result, we did not find a clinically significant difference between meniscus repair and meniscectomy during primary ACLR regarding patient-reported outcomes in a short-term follow-up. Translational potential: Our research supports the prompt integration of findings into clinical practice for treating meniscus injuries during ACL reconstruction. We recommend considering both meniscus repair and meniscectomy, as the available data indicate their effectiveness. Further studies are necessary to assess the long-term impacts, particularly on osteoarthritis, and to identify patient subgroups that may benefit most from each technique.

Background: Meniscal repair has been associated with long-term benefit in patients compared with meniscectomy. As a generalization, meniscal repair in older patients is less likely to be successful, leading to reduced adoption of meniscal repair compared with younger patients. Purpose: To establish the clinical performance of meniscal repair in "older" patients (age, ≥40 years) and compare it with performance in "younger" patients (age, <40 years). Study Design: Systematic review; Level of evidence, 4. Methods: A systematic literature review was performed in September 2021 using Embase and PubMed to identify published English-language studies that reported on a meniscal repair in >5 patients aged ≥40 years. Outcomes of interest were success/failure rate (as defined by the study), revision meniscal procedure rate, and patient-reported outcomes. Meta-analyses were used to synthesize outcomes across all studies in older patients. Meta-analyses were also used to compare outcomes between older and younger patients across studies, providing data on both age groups. Results: Fourteen studies were identified. Meniscal repair in older patients was determined to have a failure rate of 12% (95% CI, 7.3% to 19.4%) and a revision meniscal procedure rate of 9.8% (95% CI, 6.2% to 15.0%). The postoperative Lysholm score was 86.7 (95% CI, 81.7 to 91.7). No statistically significant differences were observed between older and younger patients in failure rate (relative risk [RR], 0.73 [95% CI, 0.44 to 1.21]; P =.2205), revision meniscal procedure rate (RR, 0.69 [95% CI, 0.41 to 1.16]; P =.1613), or Lysholm scores (mean difference, 2.3 [95% CI, –4.7 to 9.2]; P =.5278, 4 studies). Conclusion: Meniscal repair in selected patients aged ≥40 years resulted in good success rates and patient-reported outcome measures, which appear similar to those reported for patients aged <40 years. Therefore, meniscal repairs can be performed in at least a specific portion of "older" patients, and age per se should not be the sole determining factor in whether to perform a meniscal repair. [ABSTRACT FROM AUTHOR]

Background: The outcomes of medial meniscal allograft transplantation (MMAT) combined with high tibial osteotomy (HTO) compared with isolated MMAT remain unclear. Purpose: To compare the clinical and radiological results of MMAT combined with HTO and isolated MMAT. Study Design: Cohort study; Level of evidence, 3. Methods: This retrospective study included 42 consecutive patients, who were divided into group M (isolated MMAT; n = 22) and group H (MMAT combined with HTO with a varus angle >3°; n = 20). Group differences in subjective knee scores, isokinetic muscle strength test, and radiological outcomes (Kellgren-Lawrence grade, mechanical axis, graft extrusion, graft status, and articular cartilage loss) were compared. Results: The mean follow-up period was 29.2 ± 4.9 months and 27.4 ± 5.3 months for groups M and H, respectively. The Lysholm score improved from 55.4 ± 9.5 to 81.3 ± 9.7 and from 52.6 ± 8.9 to 84.2 ± 10.2 in groups M and H, respectively (both P <.001). The International Knee Documentation Committee subjective score improved from 51.4 ± 10.3 to 79.6 ± 9.4 and from 49.3 ± 11.4 to 81.4 ± 8.3 in groups M and H, respectively (both P <.001). Both groups showed no significant differences in subjective knee scores and isokinetic extensor strength at the final follow-up. The rate of preoperative and postoperative high International Cartilage Regeneration & Joint Preservation Society grade (≥3) did not differ between the 2 groups. Group M showed greater coronal graft extrusion than did group H (3.3 ± 0.7 mm vs 2.7 ± 0.8 mm; P =.014); the rate of pathologic graft extrusion (≥3 mm) was not higher in group M (40.9%) than in group H (20%) with the number of patients available (P =.143). Both groups showed no significant difference in the graft status. Graft tears were observed in 2 patients (9%) in group M and 1 patient (5%) in group H (P =.607). Conclusion: Clinical scores significantly improved after isolated MMAT and MMAT combined with HTO compared with preoperative values, and their short-term outcomes were similar. Postoperative graft extrusion was greater in patients who underwent isolated MMAT, implying that active correction of varus alignment during MMAT may help in intra-articular biomechanics. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to evaluate the integrity of medial meniscus root repairs performed using an inlay transosseus single-tunnel repair technique. Methods: Fifteen cadaveric fresh frozen whole knee specimens (7 left, 8 right, ages 40-62) with intact collaterals, cruciates and meniscocapsular attachments were utilized for the study. All specimens underwent diagnostic knee arthroscopy to confirm that the medial menisci (MM) were intact. Of the 15 knees, only 11 (6 left, 7 right) cadaveric specimens had intact MM and underwent further testing. One metallic tracer (Arthrex Mini Corkscrew 2.5 mm x 7 mm fully threaded anchors) were placed into the medial tibial spines and another into the midsubstance of the posterior horns of the MM in all tested specimens. The intact MM roots were then detached using arthroscopic scissors, and root repair was performed using a transosseus single-tunnel repair technique (Arthrex 6 mm FlipCutter, two 0 FiberLink luggage tag sutures, one 4.75 mm PEEK SwiveLock anchor). The knee specimens were then attached to a proprietary jig and loaded in full extension using an Instron. Mini C-arm fluoroscopic anterior posterior views were obtained to document the posterior horn/medial tibial spine metallic tracer spatial relationships. The knee specimens underwent the following loading conditions: 1. Intact MM loaded statically with 1700 N (roughly 2.5 x body weight for a 75 kg patient). 2. Cut MM loaded statically with 1700 N. 3. Repaired MM loaded statically with 1700 N 4. Repaired MM root after cyclic loading with 1700 N x 250 cycles and then loaded statically with 1700 N in full extension. The knee specimens underwent repeat knee arthroscopy after cycling to assess the clinical integrity of the MM root repairs. Post hoc measurements were performed between the medial tibial spine/posterior horn metallic tracers to calculate meniscal displacement in the different loading scenarios. Results: All 11 tested specimens demonstrated intact MM root repairs after cyclic loading upon direct arthroscopic inspection. We compared the relationship of the medial tibial spine/posterior horn MM metallic markers to the entire medial tibial plateau for each knee specimen. When comparing the different testing scenarios, we found that there was statistically significant meniscal displacement between the intact and cut MM loading states (p = 0.011). Additionally, when loading the MM root repair, we noted statistically significant meniscal displacement between the intact and repaired MM loading states (p = 0.004) and the intact versus repaired and cycled MM states (p = 0.012). There was no difference in meniscal displacement noted between the repaired and cut MM loading states (p = 0.6), and no difference in meniscal displacement between the repaired and the repaired and cycled MM states as well (p = 0.5). Conclusions: MM root repairs performed using a transosseus single-tunnel repair technique do not withstand simulated physiologic cyclic weightbearing in full extension. Although the repair construct does not catastrophically fail, the repair construct allows for high amounts of creep/strain and resulting meniscal displacement that rivals the cut state. The lack of statistical significance between all repaired and cut states indicates that there is unacceptable meniscal displacement with this repair technique. This research highlights the clinical importance that creep/strain within a construct can pose, and correlates positively with recent publications regarding this method of fixation. Direct aperture fixation at the tibial plateau articular surface would theoretically perform better for MM root tears because it would allow for diminished working length of the construct, ultimately decreasing strain. [ABSTRACT FROM AUTHOR]

Background: Collagen meniscal implant (CMI) is considered an effective procedure for reducing knee pain and improving knee function after previous meniscectomy. Nevertheless, the current knowledge regarding long-term patient reported-outcome measures after CMI is limited. Purpose: To evaluate clinical outcomes, reoperations, and failures of CMI at a minimum 10-year follow-up. Study Design: Case series; Level of evidence, 4. Methods: Consecutive patients who underwent CMI at a single institution were screened for eligibility. Inclusion criteria for the present study were (1) medial or lateral CMI; (2) isolated or combined procedure with anterior cruciate ligament reconstruction, knee osteotomy, or cartilage treatment; and (3) follow-up between 10 and 15 years. Demographics and surgical details were obtained via chart review. Patients were asked if they were satisfied with the procedure and were evaluated with the Lysholm score, Knee injury and Osteoarthritis Outcome Score (KOOS), visual analog scale for pain, and Tegner score at the final follow-up. Cases requiring partial or total scaffold removal for any reason (including scaffold breakage, infection, or surgery for osteoarthritis progression) were considered surgical failure. Survival analysis was performed with Kaplan-Meier curve, and clinical scores were analyzed based on the Patient Acceptable Symptom State (PASS). Results: A total of 92 patients (mean age, 42.2 years were included in the analysis. A significant improvement in all clinical scores was reported between the preoperative evaluation and the last follow-up. A chondropathy with Outerbridge grade ≥3 was associated with significantly overall lower clinical scores, while a timing from meniscectomy to CMI of ≥5 years determined more pain at rest and reduced Quality of Life in the KOOS subscale. No significant difference was found in terms of clinical scores between patients undergoing isolated and combined procedures. At the final follow-up, the mean Lysholm score was 76.3 points. In total, 12 cases (13%) were considered surgical failures. Sixteen patients (17%) did not reach PASS for the Lysholm score, with a total of 28 cases (30%) classified as clinical failures. Overall, 19% (KOOS Pain) and 40% (KOOS Symptoms) of patients did not achieve the PASS in the KOOS subscales. Chondropathy with Outerbridge grade ≥3 was associated with a higher risk of not achieving the PASS in all the KOOS subscales, while age at surgery of ≥45 years resulted in a lower risk of not achieving PASS in the Pain subscale. At the last follow-up, 63% of patients were still involved in sports activity, with 41% at the same or higher level. Finally, 80% of the patients were satisfied with the procedure. Conclusion: Up to 10 years after surgery, around 70% of the patients who underwent CMI reported satisfactory clinical results, with clinical subjective scores still higher compared with the preoperative evaluation. Overall, 30% of cases were considered clinical failures, with 13% considered surgical failures and 17% not meeting the PASS for the Lysholm score. In addition, cartilage status and time from meniscectomy were shown to have a negative impact on the outcomes, while an age ≥45 years was associated with less pain. There was no clinical difference between patients who underwent isolated CMI or combined procedures. [ABSTRACT FROM AUTHOR]

Purpose of the study: This study aimed to reach a consensus for ideal surgical treatment of discoid lateral meniscus (DLM) and to evaluate its long term surgical and radiological outcome. Methods: All authors independently searched for peer reviewed publications with keywords like discoid lateral meniscus, tibial menisci abnormalities, tibial menisci surgery and clinical outcome and their representative Medical Subjects Headings (MeSH) in databases of PubMed, EBSCO, Cochrane Central Register of Controlled Trials, from inception to December 2022. Original articles in English language on discoid lateral meniscus reporting clinical, surgical, or radiological outcomes with five or more years of follow-up were included in this systematic review. Study details and outcome data were analysed according to the age, follow-up period, kind of surgery, DLM type, and alignment. Results: Our search strategy yielded 654 articles in PubMed, 222 articles in EBSCO and 5 articles in CENTRAL i.e. a total of 881 articles. After detailed assessment and screening, 12 articles were included in the final analysis, which included 444 DLM cases. The mean patient age at surgery ranged from 9.9 to 35.9 years, and the mean follow-up period ranged from 5.2 to 16 years. Partial meniscectomy and meniscoplasty are the recommended treatment because of the concerns of degenerative arthritis development after the total and subtotal meniscectomies. Two studies have documented better results with meniscal allograft transplantation. Conclusion: Satisfactory clinico-radiological outcome can be obtained after surgical treatment of discoid lateral meniscus with meniscus reshaping and repair of peripheral unstable part. Meniscal allograft transplantation (MAT) is gaining popularity in patients with total meniscectomy with satisfactory long term functional outcome. [ABSTRACT FROM AUTHOR]

Background: Satisfactory clinical results of meniscal allograft transplantation (MAT) have been reported in recent years. However, it remains unclear whether the clinical outcomes of MAT when combined with an osteotomy are inferior to those of isolated MAT. Purpose: To compare the survival rates and clinical outcomes of patients who received isolated medial MAT with those of patients undergoing medial MAT combined with high tibial osteotomy (HTO). Study Design: Cohort study; Level of evidence, 3. Methods: A total of 55 patients underwent arthroscopic medial MAT using the soft tissue technique and HTO (mean age, 41.3 ± 10.4 years; 9 female); after fuzzy case-control matching on demographics, 55 controls who underwent isolated medial MAT were also included. Survival analyses were performed using the Kaplan-Meier method with surgical failure, clinical failure (Lysholm score, <65), and reoperation as endpoints. Subjective clinical scores were collected preoperatively and at the final follow-up. Results: The mean follow-up time was 5.4 years, up to 8 years. All outcomes significantly improved at the last follow-up (P <.001). No differences were identified between MAT and MAT + HTO groups preoperatively and at the last follow-up (P >.05). At the final follow-up, 8 of 55 (14.5%) of the MAT + HTO patients and 9 of 55 (16.4%) of the MAT patients had a Lysholm score <65 (P =.885). Overall, 90% of the patients declared they would repeat the surgery regardless of the combined procedure. Surgical failure was identified in 6 of 110 (5.5%) patients: 5 of 55 (9.1%) in the MAT + HTO group and 1 of 55 (1.8%) in the MAT group (P =.093). Clinical failure was identified in 19 of 110 (17.3%) patients: 11 of 55 (20%) in the MAT + HTO group and 8 of 55 (14.5%) in the MAT group (P =.447). A significantly lower survivorship from surgical failure was identified in the MAT + HTO group (hazard ratio, 5.1; P =.049), while no differences in survivorship from reoperation and clinical failure were identified (P >.05). Conclusion: Patients undergoing medial MAT + HTO showed similar clinical results to patients undergoing isolated medial MAT at midterm follow-up, and thus a surgically addressed malalignment does not represent a contraindication for medial MAT. However, the need for a concomitant HTO is associated with a slightly higher failure rate over time. [ABSTRACT FROM AUTHOR]

Although arthroscopic meniscus repair is the definitive treatment for meniscal tears, some patients have the fear of undergoing such surgery. In this study, we hypothesized that patients with meniscal tears would have a specific reason to avoid arthroscopic meniscus repair and that those who had opted for or avoided surgery would differ in terms of sociodemographic data, preoperative concerns regarding surgery, and/or functional status. A total of 176 patients (32 males, 144 females; mean age: 46.32±11.80 years) were included in the study. All patients had been diagnosed with meniscal tears by clinical and radiological examinations (X-ray, MRI) and recommended surgical treatment between 2018 and 2020. A single question was asked to the patients: “Why would you like to avoid surgery?” and their answers were recorded. In 63.6% of the patients, the reason for avoiding surgery was the fear of not being able to walk. Similarly, 59.1% of the patients stated that they had a fear of getting worse after surgery. More than half (54.5%) of the patients said that they knew people who had undergone similar surgery and did not benefit from it. A great majority (90.9%) of the patients stated that they had concerns about being bedridden after surgery. The proportion of the patients who thought no one would take care of their children if they had an operation was 27.3%. About 80% of the patients inquired whether they could receive an alternative conservative treatment before the surgery. Over half (59.1%) of the patients thought that they would not recover even if they underwent surgery. The most obvious reason for patients avoiding surgery was the fear of getting worse than the current state. [ABSTRACT FROM AUTHOR]

Background: Medial opening-wedge high tibial osteotomy (MOWHTO) is performed to treat young adults with medial compartment knee osteoarthritis associated with varus deformity. However, factors influencing joint space width (JSW) vary according to the type of medial meniscal tear and have not yet been completely elucidated. Purpose: To examine changes in JSW according to the type of medial meniscal tear after MOWHTO and analyze the influencing factors. Study Design: Cohort study; Level of evidence, 3. Methods: This study was conducted on 134 patients who underwent MOWHTO for medial osteoarthritis and were followed up for >2 years. The patients were classified into 3 groups based on medial meniscal status: intact, nonroot tear, and root tear. The authors then measured the JSW preoperatively and at 3 months, 6 months, 1 year, and >2 years postoperatively; analyzed whether the change in JSW varied according to meniscal status; and determined the association of these changes with the preoperative cartilage grade of the medial femoral condyle (MFC) and medial tibial plateau (MTP). International Knee Documentation Committee (IKDC) scores were used to evaluate clinical function. Results: Of the 134 patients, the medial meniscus was intact in 29 patients, a nonroot tear was observed in 58 patients, and a root tear was observed in 47 patients. Postoperatively, JSW increased for all groups, but the timing of the increase varied between the groups (P <.001). JSW increased the most 6 months postoperatively in the intact group and 3 months postoperatively in the nonroot tear and root tear groups (P <.001). Additionally, the increase in JSW was the greatest in the root tear group. Preoperatively, MFC and MTP cartilage status differed among the groups; MTP status did not affect the JSW, but MFC status did (P <.001). The IKDC score increased from the preoperative to postoperative time point in all groups, but there was no significant difference between groups. Conclusion: The authors observed that the amount and timing of increase in JSW were dependent on the pattern of medial meniscal tear observed when MOWHTO was performed. In addition, the cartilage grade of MFC before surgery was associated with changes in JSW. The IKDC score was not significantly different between groups. However, a longer follow-up period is needed to analyze the correlation with the meniscal tear pattern and JSW. [ABSTRACT FROM AUTHOR]

Background: Recently, all-suture, all-inside meniscal repair devices—including devices containing flat sutures or tapes—have been introduced. Similar to those in suture anchors, these modifications may have different performance characteristics than conventional sutures and polyether ether ketone (PEEK)-anchored devices. Purpose: To compare the biomechanical characteristics of all-suture meniscal repair devices with those of a conventional PEEK-anchored device and an inside-out meniscal suture construct. Study Design: Controlled laboratory study. Methods: A total of 48 adult porcine menisci with simulated bucket-handle tears were included. Single-device repairs were performed with the SuperBall Meniscal Repair System, FiberStitch, and FAST-FIX 360 with 2 PEEK anchors, and a vertical mattress inside-out suture repair was performed using a Ti-Cron No. 2-0 braided polyethylene terephthalate suture. All specimens were preloaded (10 N) and cycled 200 times (between 10 and 50 N). Specimens surviving cyclic loading were then destructively tested. Endpoints included maximum failure load, stiffness, cyclic displacement, and failure mode. The goal was 12 successful tests in each group. Metrics between groups were compared using analysis of variance with post hoc tests to control for multiple comparisons. Results: The SuperBall (108.9 N) was significantly stronger than the FAST-FIX 360 (67.3 N) and Ti-Cron (75.2 N), and the FiberStitch (102.8 N) was significantly stronger than the FAST-FIX 360 (P ≤.01 for all). Cyclic stiffness increased during cyclic loading for all constructs (P <.001). The Ti-Cron was significantly stiffer than the SuperBall during 5 to 200 cycles (P <.001). Cyclic displacement significantly increased in all constructs during cycling (P <.001) but did not differ between devices. Failure mode varied by device: the Ti-Cron repairs failed because of suture breakage, the SuperBall and FAST-FIX 360 failed at the anchor, and the FiberStitch showed both failure modes. Conclusion: The all-suture, all-inside meniscal repair devices demonstrated superior strength to the PEEK-anchored device and the classic inside-out suture meniscal repair but no statistically significant difference in cyclic displacement. [ABSTRACT FROM AUTHOR]

Background: As a subset of symptomatic discoid lateral meniscal (DLM) tears, anterior horn (AH) meniscal tears are not well studied in the pediatric population. There are even fewer studies reporting patient-reported outcomes after surgical treatment of AH tears in DLM. Purpose: To compare reported outcomes after surgical treatment of DLM tears involving the AH versus other locations in pediatric patients. Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective review of prospectively collected patient data between 2013 and 2020 was conducted. Patients aged <18 years who underwent arthroscopic treatment of a symptomatic DLM were included. Pathology was classified as tears of the AH or tears not involving the anterior horn (NAH). Demographic data along with patient-reported outcome scores (Pediatric International Knee Documentation Committee [Pedi-IKDC] and Patient Assessment Questionnaire [PAQ]) were collected preoperatively through 24 months of follow-up. Results: A total of 41 patients were included (median age, 12.9 years; range, 7-17 years; 32% female, 68% male). The mean follow-up time for was 25 months (range, 8-58 months). There were 17 (41%) patients in the AH group and 24 (59%) patients in the NAH group. Of the AH group, 16 (94%) were treated with meniscal repair (vs menisectomy), while 19 (79%) of the NAH group were treated with meniscal repair. All patients achieved significant pre- to postoperative improvement on both the Pedi-IKDC and the PAQ. At 24-month follow-up, there were no differences between the AH and NAH groups on the Pedi-IKDC (92.51 vs 89.72; P = .18) or the PAQ (2.57 vs 2.61; P = .06). Conclusion: Patients who underwent meniscal repair for AH DLM reported positive postoperative outcomes. [ABSTRACT FROM AUTHOR]

Background: Anterolateral knee laxity (ALLx) has been linked to tears of the lateral meniscus (LM) and anterior cruciate ligament (ACL) injury. Purpose: To investigate the longitudinal relationship between the signal intensity (SI) of the repaired LM on magnetic resonance imaging (MRI) and residual ALLx after ACL reconstruction (ACLR). Study Design: Cohort study; Level of evidence, 3. Methods: Included were 87 patients who underwent double-bundle ACLR and lateral meniscal repair (mean age, 23.5 years; body mass index, 23.7 kg/m2; 56 women) at a single institution between 2010 and 2019. Proton density-weighted (PDW) and T2-weighted (T2W) MRI was performed at 3, 6, and 12 months postoperatively, and the SI ratio (SIR) was calculated as (SI of the repaired LM)/(SI of the posterior cruciate ligament). At the 12-month follow-up, ALLx was evaluated using the pivot-shift test; an International Knee Documentation Committee grade ≥1 indicated residual ALLx. Results: Overall, 12 patients (13.8%) exhibited ALLx at 12 months postoperatively. At 3 months postoperatively, the SIR on PDW images (SIR-PDW) was significantly higher in patients with ALLx versus those without ALLx (1.98 ± 0.77 vs 1.49 ± 0.52, respectively; P = .007); there was no difference in the SIR on T2W images between the groups. SIR-PDW at 3 months postoperatively was correlated negatively with patient age (r = -0.308, P = .004). When patients were stratified into a younger (≤22 years; n = 53; ALLx = 7 [13.2%]) and an older (>22 years; n = 34; ALLx = 5 [14.7%]) group, the area under the receiver operating characteristic curves (AUCs) for SIR-PDW in the younger group were statistically significant for predicting the prevalence of ALLx at all follow-up times (AUCs, 0.733-0.788) with optimal cutoff values of 2.00 at 3 months, 1.50 at 6 months, and 1.50 at 12 months. Logistic regression analysis revealed that if younger patients consistently had higher SIR-PDW values than the cutoff values, they were more likely to have residual ALLx (odds ratios, 10.24-23.57). Conclusion: For younger patients who underwent both ACLR and lateral meniscal repair, higher MRI SI of the repaired LM was associated with a higher prevalence of residual ALLx. [ABSTRACT FROM AUTHOR]

Background: While posterior medial meniscus root (PMMR) techniques have evolved, there remains a need to both optimize repair strength and improve resistance to cyclic loading. Hypothesis: Adjustable tensioning would lead to higher initial repair strength and reduce displacement with cyclic loading compared with previously described transtibial pull-out repair (TPOR) fixation techniques. Study Design: Controlled laboratory study. Methods: A total of 56 porcine medial menisci were used. Eight intact specimens served as a control for the native meniscus. For the others, PMMR tears were created and repaired with 6 different TPOR techniques (8 in each group). Fixed PMMR repairs were executed using 4 different suture techniques (two No. 2 cinch sutures, two cinch tapes, two No. 2 simple sutures, and two No. 2 sutures in a Mason-Allen configuration) all tied over a cortical button. Adjustable PMMR repairs using Mason-Allen sutures were fixed with an adjustable soft tissue anchor fixation tensioned at either 80 N or 120 N. The initial force, stiffness, and relief displacement of the repairs were measured after fixation. Repair constructs were then cyclically loaded, with cyclic displacement and stiffness measured after 1000 cycles. Finally, the specimens were pulled to failure. Results: The PMMR repaired with the 2 cinch sutures fixed technique afforded the lowest (P < .001) initial repair load, stiffness, and relief displacement. The adjustable PMMR repairs achieved a higher initial repair load (P < .001) and relief displacement (P < .001) than all fixed repairs. The 2 cinch sutures fixed technique showed an overall higher cyclic displacement (P < .028) and was completely loose compared with the native meniscus functional zone. Repairs with adjustable intratunnel fixation showed displacement with cyclic loading similar to the native meniscus. With cyclic loading, the Mason-Allen adjustable repair with 120 N of tension showed less displacement (P < .016) than all fixed repairs and a stiffness comparable to the fixed Mason-Allen repair. The fixed Mason-Allen technique demonstrated a higher ultimate load (P < .007) than the adjustable Mason-Allen techniques. All repairs were less stiff, with lower ultimate failure loads, than the native meniscus root attachment (P < .0001). Conclusion: Adjustable TPOR led to considerably higher initial repair load and relief displacement than other conventional fixed repairs and restricted cyclic displacement to match the native meniscus function. However, the ultimate failure load of the adjustable devices was lower than that of a Mason-Allen construct tied over a cortical button. All repair techniques had a significantly lower load to failure than the native meniscus root. Clinical Relevance: Knotless adjustable PMMR repair based on soft anchor fixation results in higher tissue compression and less displacement, but the overall clinical significance on healing rates remains unclear. [ABSTRACT FROM AUTHOR]

Objectives: Anterior cruciate ligament reconstruction (ACLR) restores passive knee stability but does not reduce the rate of osteoarthritis (OA). Meniscal status, requiring repair or meniscectomy, is a known component of degenerative progression. Regarding the patellofemoral joint (PFJ) specifically, traditional imaging modalities have shown some evidence that patellar tendon autograft (BPTB) is associated with an increased risk of OA. T2 relaxation time using quantitative MRI (qMRI) is an established method to identify early cartilage changes. However, T2 relaxation in the PFJ as a function of graft type and meniscal status has not been previously evaluated. We aimed to evaluate the effect of autograft type (BPTB, hamstring [HT] and quadriceps tendon [QT]) as well as concomitant meniscal surgery (repair or meniscectomy) at the time of ACLR on T2 relaxation time in PFJ cartilage. We hypothesized that BPTB grafts, concomitant meniscal repair, and meniscectomy would result in higher (worse) T2 relaxation times at 6 months after ACLR. We also evaluated the effect of abnormal joint loading during gait on the PFJ cartilage. We hypothesized that T2 relaxation times would not differ in any group after controlling for knee joint loading during walking. Methods: Thirty-four participants aged 15-35 years were enrolled prospectively within 1 month of ACL injury. Exclusion criteria included prior knee injury or surgery, concomitant grade III tear to other knee ligaments that was symptomatic or required surgical intervention and presence of chondral damage. Sagittal qMRIs were obtained within 1 month of injury (but prior to ACLR) and 6 months after ACLR. Articular cartilage of the PFJ was manually segmented using ITK-SNAP software (Penn Image Computing and Science Laboratory, University of Pennsylvania) and was confirmed for accuracy by a board-certified, fellowship-trained musculoskeletal radiologist (Figure 1). Mean T2 relaxation times were extracted from the trochlear and patellar cartilage. Non-physiological T2 relaxation times less than 10 ms and greater than 90 ms were excluded. Gait biomechanics were captured using two in-ground force plates (Bertec Corporation, Columbus, OH) sampled at 1,080 Hz and retroreflective markers with an 8-camera motion capture system (Qualisys, Göteborg, Sweden) sampled at 120 Hz. Data was processed using Visual 3D software (C-motion, Bethesda, MD). Using an inverse dynamic approach, joint angle and force plate data were used to calculate the knee flexion moment (KFM) impulse normalized to mass and height during the stance phase. Separate one-way ANOVAs were used to evaluate the relationship between graft type and concomitant meniscus surgery with the percent change in T2 relaxation time in PFJ cartilage from baseline to 6 months after ACLR. To determine the influence of gait biomechanics on T2 relaxation time across groups, general linear models were used with the interlimb ratio (involved/uninvolved) of KFM impulse as a covariate. Results: The 34 participants had a mean age of 19.0±4.7 years, and 21 (61.8%) were female. Grafts used during ACLR included 22 BPTB, 4 HT and 8 QT. Seventeen participants (50.0%) had a concomitant meniscus repair and 3 (8.8%) had a meniscectomy. Overall, T2 relaxation time increased 8.7±7.3% in the patellar cartilage (pre-ACLR: 39.1±2.6 ms, 6 months: 42.4±3.6 ms, p<0.001) and 7.1±7.3% in the trochlear cartilage (pre-ACLR: 46.3±2.6 ms, 6 months: 49.5±2.7 ms, p<0.001). The change in T2 relaxation time 6 months after ACLR did not differ based on graft type in either the patellar (p=0.729) or trochlear cartilage (p=0.525) (Figure 2). Group differences remained insignificant after controlling for knee loading (KFM impulse) during gait (patellar: p=0.594; trochlear: p=0.222). Meniscal status was also not associated with a change in T2 relaxation time in either the patellar (p=0.392) or trochlear cartilage (p=0.190) (Figure 3) although there was a trend toward higher T2 relaxation times in those with a concomitant meniscus repair or meniscectomy. Group differences remained statistically insignificant after controlling for the KFM impulse during gait (patellar: p=0.400; trochlear: p=0.197). Conclusions: Our findings provide insufficient evidence that graft type is associated with worse quantitative chondral changes within the PFJ at 6 months following ACLR. While meniscal status is a known risk factor for increased contact pressure in the involved compartment and subsequent degenerative progression, our data does not demonstrate statistically significant changes to the PFJ cartilage when meniscal tears were present, likely due to the limited sample size and large variation within groups. Future work with larger cohorts is needed to confirm our findings and further investigate the role that graft type and meniscal status may play within the PFJ after ACLR. [ABSTRACT FROM AUTHOR]

Objectives: Root tears encompass avulsion injuries affecting the bony or soft tissue root attachments of the meniscus, as well as radial tears occurring within 1 cm of these attachment points. Meniscal root tears have been increasingly recognized as contributors to early onset osteoarthritis and disrupted joint kinematics and insights from animal, cadaveric, and clinical studies have resulted in a paradigm shift from meniscectomy towards repair. The purpose of this study is to define the minimal clinically important difference (MCID) and patient-acceptable symptomatic state (PASS) for patient-reported outcome measures (PROMs) following isolated posterior medial meniscal root repair (PMMR) and to investigate the role of preoperative, demographic, and intraoperative variables for predicting achievement of these thresholds. We hypothesized that patients have a greater likelihood of achieving MCID with lower preoperative outcome scores and a greater likelihood to achieve PASS with higher preoperative outcome scores. Furthermore, certain preoperative and intraoperative factors are likely to influence achievement of MCID and PASS following PMMR. Methods: This is an IRB approved retrospective study of prospectively collected data from a single, high-volume institution. Inclusion criteria were patients who underwent arthroscopic PMMR performed by one of three fellowship-trained attending surgeons with a minimum of two year postoperative follow up. Exclusion criteria consisted of patient with KL grade >3 osteoarthritis and concomitant ligamentous procedures. Patients who had ipsilateral knee surgery within 2 years of undergoing meniscal root repair were also excluded. PROMs were collected from January 2017 to September 2023 and an electronic medical record was reviewed for demographic variables, intraoperative details, and postoperative complications. PROMs analyzed in this study include the International Knee Documentation Committee Score (IKDC), the Knee Injury and Osteoarthritis Outcome Score Jr. (KOOS Jr.) and the Veterans Rand 12 Physical Function (VR12 P). MCID was determined to be one-half the standard deviation of the difference from baseline in PROM scores at minimum two-year follow-up. PASS thresholds were calculated using an anchor-based approach. Receiver operating characteristic (ROC) analysis for the calculation of PASS was conducted and optimal thresholds were calculated using the Youden Index to maximize the sensitivity and specificity of threshold values. Multivariate logistic regression analyses were conducted to identify patient-related factors at baseline and intraoperative variables associated with the attainment of MCID and PASS. Results: Seventy patients were included in the final analysis. The demographics of included patients is listed in Table 1. The mean preoperative score, mean postoperative score, MCID threshold, MCID achievement rate, PASS threshold, and PASS achievement rate for IKDC, KOOS Jr., and VR12 physical are listed within Table 2. The predictive value for all PASS thresholds was good to excellent, with AUC values for IKDC, KOOS Jr., and VR12 Physical being 0.858, 0.864, and 0.755, respectively (Figure 1). For IKDC, lower BMI (OR 0.73, p = 0.03) and lower preoperative score (OR 0.94, p = 0.02) were predictive of MCID achievement, whereas lower BMI (OR 0.87, p < 0.01) and greater preoperative score (OR 1.04, p = 0.04) were predictive of PASS achievement. For KOOS Jr., use of two sutures (OR 6.98, p < 0.01) was predictive of MCID achievement, whereas use of two sutures (OR 6.91, p < 0.01) and lower BMI (OR 0.81, p < 0.01) were predictive of PASS achievement. For VR12 Physical scores, younger age (OR 0.92, p = 0.04), lower BMI (OR 0.84, p = 0.01), and lower preoperative score (OR 0.89, p < 0.01) were predictive of MCID achievement, whereas use of two sutures (OR 7.24, p = 0.02), lower BMI (OR 0.92, p < 0.01), and greater preoperative score (OR 1.19, p = 0.02) were predictive of PASS achievement. Conclusions: This study defines the thresholds for MCID and PASS achievement at minimum two-year follow-up for IKDC, KOOS Jr., and VR12 Physical scores in a large cohort of patients undergoing isolated posterior-medial meniscal root repair at a single, high-volume institution. More patients achieved MCID than PASS. Lower BMI, use of fewer sutures, and preoperative scores were the most common predictors of MCID and PASS achievement. Additionally, younger age was an independent predictor of MCID achievement for VR-12 Physical Function. [ABSTRACT FROM AUTHOR]

Context: Recently, blood flow restriction (BFR) training has gained popularity as an alternative to high-load resistance training for improving muscle strength and hypertrophy. Previous BFR studies have reported positive treatment effects; however, clinical benefits to using BFR following meniscal repair or chondral surgery are unknown. The purpose of this study was to determine the effect of resistance exercises with BFR training versus exercises alone on self-reported knee function, thigh circumference, and knee flexor/extensor strength postmeniscal or cartilage surgery. Design: Single-blinded randomized controlled trial in an outpatient military hospital setting. Twenty participants were randomized into 2 groups: BFR group (n = 11) and control group (n = 9). Methods: Participants completed 12 weeks of postoperative thigh strengthening. The BFR group performed each exercise with the addition of BFR. Both groups continued with the prescribed exercises without BFR from 12 weeks until discharged from therapy. Thigh circumference and self-reported knee function were measured at 1, 6, 12, and 24 weeks postoperatively along with knee extensor and flexor strength at 12 and 24 weeks. Change scores between time points were calculated for knee function. Limb symmetry indices (LSI) were computed for thigh circumference and knee strength variables. Results: Seventeen participants were included in the final analyses (BFR = 8 and control = 9) due to COVID-19 restrictions. There were no interactions or main effects for group. Time main effects were established for change in knee function scores, thigh circumference LSI, and knee extensor strength LSI. However, knee flexor strength LSI had no main effect for time. Conclusion: The outcomes of this trial suggest that resistance exercises with and without BFR training may result in similar changes to function, thigh atrophy, and knee extensor strength postmeniscus repair/chondral restoration, though further study with larger sample sizes is needed. [ABSTRACT FROM AUTHOR]

Objective. Females have reduced osteoarthritis (OA) in surgical models. The objective of the current study was to evaluate a sex-linked gut microbiome in the pathogenesis of OA. Methods. We induced OA via destabilization of the medial meniscus surgery in adult male and female C57BL6/J mice with and without opposite-sex microbiome transplantation. Eight weeks later, animals were euthanized, and OA severity, synovitis, and osteophyte scores were determined. Serum lipopolysaccharide was measured chromogenically, and serum cytokines were quantified via multiplex immunoassay. Cecal microbiome profiles were generated using 16S deep sequencing. Results. Males had worse OA histology (3.5x, P = 6 × 10−7 ), synovitis (2.4x, P = 5 × 10−4 ), and osteophyte scores (3.7x, P = 3 × 10−4 ) than females. Male-into-female transplantation worsened all outcomes (histology 1.8x, P = 0.02; synovitis 2.0x, P = 3 × 10−5 ; osteophyte 2.1x, P = 0.01) compared to females, whereas female-into-male transplantation improved all outcomes except for synovitis (histology 0.53x, P = 2 × 10−4 ; osteophyte 0.28x, P = 5 × 10−4 ) compared to males. In the gut microbiome analysis, 44 clades were different in at least one group comparison; 5 clades were correlated with the Osteoarthritis Research Society International score (Lactobacillus R = −0.40, Aldercreutzia R = −0.40, rc4_4 R = −0.55, Sutterella R = −0.37, and Clostridiales R = 0.36). In the cytokine analysis, 10 analytes were different in at least one group comparison; 3 were different in two groups (female and female-into-male transplants vs male comparisons, all reduced in female and female-into-male transplants), including interleukin-12 (0.66x, P = 0.02; 0.66x, P = 0.02, respectively), eotaxin (0.74x, P = 5 × 10−6 ; 0.57x, P = 0.03), and tumor necrosis factor α (0.49x, P = 0.03; 0.52x, P = 0.009). Conclusion. Sex-linked differences in the mouse gut microbiome are associated with OA outcomes, are reversible by opposite-sex microbiome transplantation, and are associated with serum cytokine changes. [ABSTRACT FROM AUTHOR]

Background: Meniscal allograft transplantation (MAT) is an accepted and effective treatment option in the context of unsalvageable menisci, particularly in young and active patients. It has been shown to reduce pain and improve knee function in previously symptomatic patients. However, there is still limited knowledge about the long-term survival rates of allografts, the durability of clinical results, and the influence of patient-specific parameters, such as leg alignment, tibial slope, and preoperative International Cartilage Regeneration & Joint Preservation Society (ICRS) grade. Purpose: To determine (1) the long-term clinical success rate after MAT with bony fixation in a large, single-center cohort of consecutive patients, and (2) if patient-specific and procedural variables influence the clinical, anatomic, and subjective outcomes and risk of failure. Study Design: Case-control study; Level of evidence, 3. Methods: Data on 185 consecutive knees undergoing MAT in a single institution were prospectively collected and screened for inclusion in this study. The minimum follow-up time was 2 years. Radiographic variables (ICRS grade and Kellgren-Lawrence grade) were assessed preoperatively and at follow-up. Subjective patient-reported outcome measures (PROMs) (Lysholm score, Knee injury and Osteoarthritis Outcome Score [KOOS] including subscores, International Knee Documentation Committee [IKDC] score, and visual analog scale [VAS] score) were collected preoperatively and at follow-up. Clinical failure was defined as revision surgery due to graft failure or conversion to total knee arthroplasty. Anatomic failure was considered a tear covering >20% of the allograft, any peripheral tear, and unstable peripheral fixation leading to dislocation of the graft. Subjective failure was defined as Lysholm score ≤65. Preoperative tibial slope and leg alignment were assessed. Survival analyses were performed using the Kaplan-Meier estimate. Univariate and multivariate analyses were performed to determine risk factors for clinical and anatomic failure. Results: A total of 157 knees met inclusion criteria. After a mean follow-up time of 7 ± 3.5 years, 127 (80.9%) knees were free of clinical, anatomic, and subjective failure. Fourteen (8.9%) knees experienced clinical failure, 26 (16.6%) knees were identified as having experienced anatomic failure, and 13 (8.3%) patients experienced subjective failure with a reported Lysholm score of ≤65 at a mean follow-up of 7 years. Concurrent osteochondral allograft transplantation was identified as a predictor of both clinical (hazard ratio [HR], 4.55; 95% CI, 1.46-14.17; P =.009) and anatomic (HR, 3.05; 95% CI, 1.34-6.92; P =.008) failure. Cartilage damage of ICRS grade 3 or 4 of the index compartment conveyed an increased risk for clinical (HR, 3.41; 95% CI, 1.05-11.01; P =.04) and anatomic (HR, 3.04; 95% CI, 1.31-7.11; P =.01) failure. High-grade cartilage damage preoperatively (HR, 10.67; 95% CI, 1.037-109.768; P =.046), patient age >25 years (HR, 5.44; 95% CI, 0.120-246.070; P =.384), and a body mass index >30 (HR, 2.24; 95% CI, 0.748-6.705; P =.149) were associated with subjective failure. PROMs including KOOS and IKDC were significantly improved at final follow-up compared with preoperative scores across all measurements (P <.005). Conclusion: MAT showed good to excellent clinical results at a mean follow-up of 7 years. Low ICRS lesion grade was associated with a higher clinical and anatomic survival rate. Patients with concurrent OCA transplantation are at a higher risk of clinical and anatomic failure, but still report significantly improved PROMs. These results suggest that MAT has a lasting beneficial effect both in isolation and in complex cases with ≥1 concurrent procedures. [ABSTRACT FROM AUTHOR]

Introduction. Despite trends to repair meniscal defects, meniscectomy continues to be a common procedure. Degenerative changes following these surgeries become candidates for meniscal allograft transplantation. Purpose. The purpose of this meta-analysis was to review published articles that compared methods of meniscal allograft transplantation (bone plug, suture only, or bone bridge) for their biomechanical effects on tibiofemoral mean contact pressure and contact area in relation to intact meniscal states. Materials and methods. PubMed database search on July 15, 2020 for articles evaluating the knee kinematics of MAT in a biomechanical model. Results. The greatest contact area was found in the setting of an intact meniscal state, with a mean difference of 188.886 mm³ (95%CI 148.059-229.672, p < 0.001) and 78.713 (95%CI 78.713-103.733, p < 0.001), when compared to meniscectomy and MAT respectively. Although MAT showed a lower contact area vs the intact knee, it did have a greater contact area than meniscectomy by 94.951 mm² (95%CI, 71.590118.312, p < 0.001). The dovetail bone bridge technique was shown to have the highest difference in mean contact area of 207.676 mm² (95%CI 85.288-330.065, p < 0.001) when compared to bone plug technique. Conclusions. Meniscal allograft transfer demonstrated significantly less contact area than a meniscus intact knee and significantly higher contact area than meniscectomy. In the systematic review, bone bridge meniscal allograft transplant techniques offered the closest reproduction of native knee biomechanics when compared to bone plug and suture only. [ABSTRACT FROM AUTHOR]

Background: Medial meniscal root repairs are devastating injuries that can cause long-term knee problems if not properly addressed. Some common issues when addressing these injuries surgically include the "bungee-cord" effect seen with implants that sit too far from the tibial plateau surface and loss of tension on the sutures after cycling of the knee after the repair. This video will discuss the presentation of a patient with a medial meniscal root repair treated with a novel technique to counteract these aforementioned issues. Indications: Based on the patient's medial meniscal root tear and minimal arthritis seen on radiograph, he was indicated for a meniscal root repair to prevent meniscal extrusion and reinforce normal meniscal hoop stresses to limit progression of his arthritis. Technique Description: This technique uses a novel re-tensionable all-suture anchor through a transtibial tunnel with 2 repair sutures through the meniscal root that sits just below the tibial plateau, allowing the surgeon the ability to re-tension the implant after cycling the knee. Results: Arthroscopic repair of the medial meniscal root allowed the patient to return to his previous level of activity. Discussion/Conclusion: In this case, arthroscopic medial meniscal root repair can yield good results in patients to get them back to their previous level of activity while minimizing the chance of rapid arthritic progression that is typically seen with nonoperative management of these injuries. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication. [ABSTRACT FROM AUTHOR]

Background: Blood flow restriction (BFR) is a training tool that involves wearing a tourniquet or occlusive device during exercise. Data support that low-load training with BFR may produce muscle hypertrophy similar to standard high-load training. Because of the weight-bearing and range of motion (ROM) restrictions after meniscal repair, patients encounter substantial atrophy of lower extremity musculature. We perform BFR for these patients to limit atrophy postoperatively with the goal of facilitating their return to prior function and sports. Indications: We incorporate BFR in the postoperative rehabilitation protocol for patients undergoing meniscal repair not involving the root. Patients with the following are excluded: acute or severe cardiac disease, peripheral vascular disease, blood pressure over systolic 180 mm Hg or diastolic 100 mm Hg, hemophilia, thrombophlebitis or history of deep vein thrombosis, severe anemia, and sickle cell disease. Technique Description: An automated BFR device calculates the patient's limb occlusion pressure (LOP) and titrates to 50% to 80% of LOP for lower extremity exercises. Exercise parameters typically consist of 4 sets of each exercise, totaling 75 repetitions, with 30-second interset rest. Patients undergo a standard 3-phase postoperative rehabilitation protocol. Phase I (weeks 0-6): Patients are nonweightbearing, may be either footflat weightbearing or partial weightbearing at the surgeon's, with ROM restricted 0 to 90 in a hinge knee brace throughout the phase. Exercises include quadriceps sets with neuromuscular electrical stimulation and straight leg raises and short/long arcs quadriceps. Phase II (weeks 7-8): Patients progress to weightbearing and ROM as tolerated and begin exercises including double mini squats, hamstring curls, double leg press, and double leg heel raises. Phase III: (weeks 9+): Patients perform double and single leg bridges, double leg bridges on ball with knee band, squats, single leg press, and single leg heel raises, all with the goal of returning to sports. Results: Prior systematic review data demonstrate low-load training with BFR increases muscle strength and induces hypertrophy relative to low-load training alone. No significant differences for Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales between BFR training group and control group. Discussion: BFR training may facilitate postoperative recovery in patients undergoing meniscal repair surgery by helping mitigate muscular atrophy. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication. [ABSTRACT FROM AUTHOR]

Background: Knee laxity increases with medial meniscectomy in anterior cruciate ligament (ACL)–reconstructed knees; however, the biomechanical effect of an additional lateral extra-articular tenodesis (LET) is unknown. Purpose/Hypothesis: The purpose of this study was to determine the kinematic effect of a LET in knees that underwent combined ACL reconstruction (ACL-R) and partial medial meniscus posterior horn (MMPH) meniscectomy. It was hypothesized that the addition of LET would reduce laxity in the ACL-reconstructed knee. Study Design: Controlled laboratory study. Methods: Ten fresh-frozen human cadaveric knees (mean age, 41.5 years) were tested using a robotic system under 3 loads: (1) 89.0 N of anterior tibial (AT) load, (2) 5 N·m of internal rotation (IR) tibial torque, and (3) a simulated pivot shift—a combined valgus of 7 N·m and IR torque of 5 N·m—at 0°, 15°, 30°, 45°, 60°, and 90° of knee flexion. Kinematic data were acquired in 4 states: (1) intact, (2) ACL-R, (3) ACL-R + partial MMPH meniscectomy (MMPH), and (4) ACL-R + partial MMPH meniscectomy + LET (MMPH+LET). Results: In response to AT loading, there was a significant increase seen in AT translation (ATT) in the MMPH state at all knee flexion angles compared with the ACL-R state, with the highest increase at 90° of knee flexion (mean difference, 3.1 mm) (P <.001). Although there was a significant decrease in ATT at 15° of knee flexion with MMPH+LET (P =.022), no significant differences were found at other knee flexion angles (P >.05). In MMPH with IR torque, a significant increase was observed in IR at all knee flexion angles except 90° compared with the ACL-R state (range, 2.8°-4.9°), and this increase was significantly decreased at all flexion angles with the addition of LET (range, 0.7°-1.6°) (P <.05). Conclusion: Performing a partial MMPH meniscectomy increased ATT and IR in response to AT and IR loads compared with the isolated ACL-R state in a cadaveric model. However, when the LET procedure was performed after partial MMPH meniscectomy, a significant decrease was seen at all knee flexion angles except 90° in response to IR and torque, and a significant decrease was seen at 15° of knee flexion in response to AT load. Clinical Relevance: LET may be a useful adjunct procedure after ACL-R with partial MMPH meniscectomy to reduce knee laxity. [ABSTRACT FROM AUTHOR]

Background: Posterior medial meniscus root (PMMR) tears are a challenge to assess and treat. However, the forces sustained at the PMMR are yet to be fully characterized. In addition, it has been shown that meniscotibial ligament (MTL) injuries happen before PMMR tears, suggesting that insufficiency of the MTL results in a change of forces acting on the PMMR. Purpose/Hypothesis: The purpose of this study was to evaluate the 3-dimensional forces acting on the PMMR in the intact, MTL cut, and MTL tenodesis states. It was hypothesized that the MTL cut state would increase medial shear forces seen at the PMMR, whereas the medial shear force in the MTL tenodesis state would return PMMR forces to that of the intact state. Study Design: Controlled laboratory study. Methods: Ten fresh-frozen cadaveric knees were tested in 3 states (intact, MTL cut, and tenodesis). A 3-axis load cell was installed below the posterior tibial plateau and attached to the enthesis of the PMMR. The specimen was mounted to a load frame that applied an axial load, an internal torque, and an external torque. The amount of compression-tension, mediolateral shear force, and anteroposterior shear force acting on the PMMR was measured. Results: When the joint was loaded in compression, the MTL cut state significantly increased compression of the PMMR (P =.0368). The tenodesis state did not significantly restore forces of the PMMR (P =.008). When the joint was loaded in external torque, the MTL cut state significantly increased compression (P <.0001) and significantly decreased anterior shear on the PMMR (P =.0003). The tenodesis state did not significantly restore forces on the PMMR to the intact state (P <.0001). Increased flexion angle significantly increased medial shear forces of the PMMR when the joint was loaded in compression (P <.007 at every angle). Conclusion: When evaluated biomechanically, MTL insufficiency resulted in increased compressive force at the PMMR. A single-anchor centralization procedure did not restore PMMR forces to that of the intact state. Increased knee flexion angle resulted in increased medial shear force on the PMMR. Clinical Relevance: The findings in this study provide clinicians information on PMMR forces when the MTL is disrupted. These data can aid in the decision-making for adding an MTL repair to augment PMMR repairs. [ABSTRACT FROM AUTHOR]

Background: Unlike the adult meniscus, the fetal meniscus possesses robust healing capacity. The dense and stiff matrix of the adult meniscus provides a biophysical barrier for cell migration, which is not present in the fetal meniscus. Inspired by developmental characteristics, modifying the matrix of the adult meniscus into a fetal-like, loose and soft microenvironment holds opportunity to facilitate repair, especially in the avascular zone. Hypothesis: Modifying the dense and stiff matrix of the adult meniscus into a fetal-like, loose and soft microenvironment could enhance cell migration to the tear interface and subsequent robust healing capacity. Study Design: Controlled laboratory study. Methods: Fresh porcine menisci were treated with hyaluronidase or collagenase. The density and arrangement of collagen fibers were assessed. The degradation of proteoglycans and collagen was evaluated histologically. Cell migration within the meniscus or the infiltration of exogenous cells into the meniscus was examined. Dendritic silica nanoparticles with relatively large pores were used to encapsulate hyaluronidase for rapid release. Mesoporous silica nanoparticles with relatively small pores were used to encapsulate transforming growth factor–beta 3 (TGF-β3) for slow release. A total of 24 mature male rabbits were included. A longitudinal vertical tear (0.5 cm in length) was prepared in the avascular zone of the medial meniscus. The tear was repaired with suture, repaired with suture in addition to blank silica nanoparticles, or repaired with suture in addition to silica nanoparticles releasing hyaluronidase and TGF-β3. Animals were sacrificed at 12 months postoperatively. Meniscal repair was evaluated macroscopically and histologically. Results: The gaps between collagen bundles increased after hyaluronidase treatment, while collagenase treatment resulted in collagen disruption. Proteoglycans degraded after hyaluronidase treatment in a dose-dependent manner, but collagen integrity was maintained. Hyaluronidase treatment enhanced the migration and infiltration of cells within meniscal tissue. Last, the application of fibrin gel and the delivery system of silica nanoparticles encapsulating hyaluronidase and TGF-β3 enhanced meniscal repair responses in an orthotopic longitudinal vertical tear model. Conclusion: The gradient release of hyaluronidase and TGF-β3 removed biophysical barriers for cell migration, creating a fetal-like, loose and soft microenvironment, and enhanced the fibrochondrogenic phenotype of reparative cells, facilitating the synthesis of matrix and tissue integration. Clinical Relevance: Modifying the adult matrix into a fetal-like, loose and soft microenvironment via the local gradient release of hyaluronidase and TGF-β3 enhanced the healing capacity of the meniscus. [ABSTRACT FROM AUTHOR]

Background: Previous biomechanical studies of the meniscotibial ligament have determined that it contributes to meniscal stability. An injury to it can cause the meniscus to extrude, and reconstruction of that ligament significantly reduces extrusion. Purpose: To assess the biomechanical effects of sectioning the lateral meniscotibial ligament (LMTL) and the meniscofibular ligament (MFL) with respect to the radial mobility of the lateral meniscus and to evaluate the biomechanical effects of the capsulodesis and centralization techniques. Study Design: Controlled laboratory study. Methods: The lateral meniscus of 22 porcine knees was evaluated. They were mounted on a testing apparatus to apply muscle and ground-reaction forces. The meniscus was evaluated at 30° and 60° of knee flexion using 2 markers placed on the posterior cruciate ligament and the lateral meniscus after applying an axial compression of 200 N to the knee joint. Measurements were recorded under 5 conditions: intact lateral meniscus, injury of the LMTL, subsequent injury of the MFL, the use of the open capsulodesis technique, and the reconstruction of the LMTL and the MFL with the centralization technique. Results: The distance between the 2 markers was significantly greater in the extrusion group (combined lesion of the LMTL and MFL) than in the intact or reconstruction groups (capsulodesis and centralization techniques; P <.001 in all cases). In the cases of load application, no significant differences were observed between the control group (intact meniscus) and the groups on which the reconstruction techniques were performed. There were also no differences when comparing the results obtained between both reconstruction techniques. In all settings, the distance between the 2 markers increased with the increase in the knee flexion angle. Conclusion: In a porcine model, the LMTL and the MFL participated as restrictors of the radial mobility of the lateral meniscus during loading. Their injury caused a significant increase in lateral meniscal extrusion, and the centralization and the capsulodesis procedures were able to reduce extrusion. Clinical Relevance: This study demonstrates the capacity of the LMTL and the MFL to restrict the radial mobility of the lateral meniscus during loading and how it is affected when they are injured. [ABSTRACT FROM AUTHOR]

Background: There are few studies examining anterior cruciate ligament reconstruction (ACLR) and RAMP lesion repair. However, no studies have investigated the level of functional performance and psychological state after ACLR and all-inside RAMP lesion repair. Hypothesis/Purpose: The aim of this study is to determine the effect of ACLR and RAMP lesion repair on psychological status. ACLR and meniscal RAMP lesion repair were hypothesized to be associated with better psychological outcomes. Study Design: This is a cohort study. Methods: Patients who underwent ACLR with semitendinosus and gracilis autografts by a single surgeon were determined retrospectively. Fifteen patients who underwent ACLR and all-inside meniscus RAMP lesion repair (ACLR-RR) and 15 patients who underwent isolated ACLR were compared. Patients were evaluated by a physiotherapist at least 9 months after surgery. The primary outcome measure was anterior cruciate ligament-return to sports after injury (ACL-RSI), and the psychological status of the patients was examined. Secondary outcomes were visual analog scale (VAS), Tegner activity score, Lysholm knee score, single hop tests, and limb symmetry index (LSI). While pain intensity at rest and during movement was evaluated with VAS, functional performance level was evaluated with the Tegner activity score, the Lysholm knee score, single hop tests, and limb symmetry index (LSI). Results: A significant difference was found in the ACL-RSI values in the ACLR-RR group compared to the isolated ACLR group (p = 0.02). The results of the groups in VAS scores at rest and during movement, Tegner activity levels, and Lysholm knee scores, in the intact and operated leg single hop tests (single leg hop, cross hop, triple hop, and six-meter hop test), and the LSI values in the single leg hop tests showed no significant difference. Conclusions: This study revealed different psychological outcomes and similar functional levels for ACLR and all-inside meniscus RAMP repair compared with isolated ACLR. It was observed that the psychological status of patients with RAMP lesions should also be evaluated. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to compare medial meniscus extrusion (MME) in patients with partial medial meniscus posterior root tears (MMPRTs) through magnetic resonance imaging (MRI) conducted at two-time points and to determine whether patient characteristics or MME measurements differ in patients who respond to nonoperative treatment compared with those who require surgical treatment. Methods: Thirty-seven patients with partial MMPRTs underwent two MRI scans during nonoperative management or before pull-out repair. Among these, 17 patients received nonoperative management, and 20 underwent pull-out repair. Partial MMPRTs were diagnosed based on the MRI findings. MME measurements were performed on both MRI scans. Statistical and receiver operating curve (ROC) analyses were performed. Results: The duration between the two MRI scans was significantly shorter in the pull-out repair group than in the nonoperative management group. The increase in MME (ΔMME) on MRI scans was significantly greater in the pull-out repair group than in the nonoperative management group. Linear regression analysis revealed a weak correlation between the MRI interval and ΔMME in the nonoperative management group and a moderate correlation in the pull-out repair group. In the ROC construction, the cut-off value for ΔMME that requires surgical intervention was 0.41 mm, with a sensitivity and specificity of 85.0% and 52.9%, respectively. Conclusion: Patients with partial MMPRTs requiring surgical treatment had greater MME progression in a shorter time and a time-dependent increase in MME. Therefore, a ΔMME of ≥ 0.41 mm may be useful in deciding surgical intervention based on MRI retests. Level of evidence: III. [ABSTRACT FROM AUTHOR]

Background: The medial and lateral menisci act as shock absorbers for the knee joint by converting and redistributing axial load into circumferential hoop stresses. Disruptions of these hoop stresses occur in the setting of meniscal deficiency and lead to long-term degenerative changes. Therefore, maintaining the distinctive composition and organization of the menisci is essential. In selective cases of meniscal deficiency, meniscus allograft transplantation can be a valuable treatment option. Indications: Meniscus transplantation should be considered in patients with symptomatic meniscal deficiency, without the presence of advanced degenerative pathologies, who have failed all conservative treatments. Technique description: We can divide the surgery into 4 steps: (1) graft preparation, (2) arthroscopic joint preparation, (3) allograft attachment preparation, and (4) graft fixation. Results: Meniscus allograft transplantation yields good to excellent results in up to 85% of cases. Improvement of pain and knee function occurs in approximately 70% of the patients at 10 years. The associated complications are mainly joint stiffness, early osteoarthritis, and incomplete healing accompanied by graft failure. Graft failure is the most feared complication, yet shows good results over the midterm. Conclusion: The bone plug technique we have shown here is a hybrid approach combining soft tissue and bone fixation techniques. It provides synergistic advantages with good osseous integration and is minimally invasive through arthroscopy without true arthrotomy. In our experience, this approach elegantly eases the complexity of this demanding surgery while yielding excellent results for patients. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication. Graphical Abstract This is a visual representation of the abstract. [ABSTRACT FROM AUTHOR]

Objectives: Coexistence of varus deformity of knee and Medial Meniscus Posterior Root Tear (MMPRT) is known to have a rapid progression to medial compartment arthritis. Medial open wedge high tibial osteotomy (MOWHTO) with transtibial suture pullout for MMPRR is currently a preferred technique, although it is technically demanding. We describe a combination of technique of root repair with an all-suture soft anchor along with MOWHTO. Methods: In this prospective study, 25 patients of proximal tibial varus of more than five degrees with MMPRT and up to grade 2 medial compartment osteoarthritis (Kellgren-Lawrence classification) were operated at a single tertiary center. Arthroscopic root repair was performed with an all-suture anchor, followed by standard MOWHTO using a titanium locking plate. Functional and radiological outcomes were evaluated at 2-year follow-up. Results: Mean deformity (femorotibial angle) improved from 12 degrees varus pre-operatively to 5 degrees valgus at 2-year follow-up. Mean MPTA increased from 80.6 to 87.2 degrees. There was statistically significant improvement in mean pre-operative Lysholm score of 32 to 85 at 2-year follow-up. Conclusions: MMPRT repair with an all-suture anchor along with MOWHTO is a relatively easier and reproducible single stage technique, giving good functional and radiological outcomes at 2-year follow-up. [ABSTRACT FROM AUTHOR]

Context: While arthrogenous muscle inhibition associated with knee injuries is evident, the relative magnitude of functional deficiency related to each individual knee pathology is unclear. Objective: To compare the knee joint and quadriceps dysfunction among patients with anterior knee pain (AKP) without surgical history and those with surgical history (anterior cruciate ligament reconstruction [ACLR]; meniscus surgery) without current AKP, with matched healthy controls. Design: Cross-sectional study. Setting: Laboratory. Participants: A total of 66 patients with knee pathologies and 30 controls. Main outcome measures: Pain perception and lower-extremity functional outcomes were assessed. Knee joint function was measured by replication tests. Quadriceps function was measured by strength, voluntary activation, and torque-generating capacity. Results: Patients with AKP reported greater pain perception compared with the other knee conditions (4.3 vs 0.1 of 10 in Numeric Pain Rating Scale, P < .0001). Compared with the controls: (1) patients with AKP showed a greater error on knee-flexion replications at 75° (2.9° vs 5.4°, P = .002), (2) patients with AKP and ACLR showed less quadriceps strength (AKP: 3.3 vs 2.6 N·m/kg, P = .002; ACLR: 3.3 vs 2.7 N·m/kg, P = .02) and voluntary activation (AKP: 0.982 vs 0.928, P < .0001; ACLR: 0.982 vs 0.946, P = .003), and (3) all knee pathologies reported lower scores on functional outcomes (79 vs 65 of 80 points in Lower-Extremity Functional Scale, P < .0001) and showed less quadriceps torque-generating capacity (10.7 vs 7.8 N·m/s/kg, P < .0001). Among the knee pathologies, patients with AKP showed less quadriceps voluntary activation compared with the patients with meniscus surgery (0.928 vs 0.964, P = .03). Conclusion: As patients with AKP had an additional impairment in knee joint flexion replications and reported a less score in functional outcomes, knee pain may produce a greater impact on functional deficiency. [ABSTRACT FROM AUTHOR]

Background: Knee instability due to posterior cruciate ligament (PCL) and posterolateral corner (PLC) deficiency is a devastating condition that negatively affects patient quality of life. This video presents the surgical management of a triple varus knee, including combined high tibial osteotomy (HTO), revision PCL and PLC reconstruction, and meniscus root repair. Indications: Combined HTO and revision PCL and PLC reconstruction is indicated for patients with previously failed PCL and PLC reconstruction in the setting of varus malalignment. Technique Description: The procedure begins with a medial opening-wedge biplanar HTO, which is fixed with a patient-specific locking plate. The PCL femoral tunnel is drilled via a low anterolateral portal, and the tibial insertion is debrided via a posteromedial portal. The medial meniscus is carefully freed from the posterior capsule, and 2 luggage tag sutures are placed through the posterior root. The PCL tibial tunnel and meniscus root tunnels are drilled via their respective guides. The meniscal sutures are passed through the tunnel but not fixed. An Achilles bone-block allograft is passed through the PCL tibial tunnel and fixed with suspensory fixation and an interference screw on the femoral side, while the tibial side is left free. A peroneal nerve neurolysis is performed. A fibular tunnel is drilled, and a semitendinosus allograft is whip-stitched on both sides and passed through the tunnel. A Beath pin is inserted into the femur, and the tunnel is over drilled. Both limbs of the graft are passed deep to the iliotibial band and into the tunnel. The tibial side of the PCL is fixed with an interference screw at 90° of knee flexion. The PLC grafts are fixed with an interference screw at 30° of knee flexion with slight valgus. The medial meniscus root sutures are tied over a button, with 60° of knee flexion. Screws from osteotomy fixation are replaced as needed. Results: Although outcomes following the combined procedure are lacking, good to excellent clinical outcomes have been reported in isolation following each procedure. Conclusion: A combination of HTO and revision PCL and PLC reconstruction should be considered for patients with persistent instability and/or pain in the setting of triple varus knee. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication. [ABSTRACT FROM AUTHOR]

Background: Quadriceps autograft, though well established for anterior cruciate ligament reconstruction, is underutilized in posterior cruciate ligament (PCL) reconstruction largely due to slow adoption. All-inside meniscal ramp repair and quadriceps tendon autograft PCL reconstruction have been described in isolation, but not concomitantly in a video journal. Indications: PCL reconstruction is indicated in grade 3 isolated tears with instability that have not improved with nonoperative management and in instances with associated injuries such as meniscal ramp tears, as observed in this 18-year-old division I football player. Graft selection is dependent upon surgeon and patient preference, with quadriceps autograft delivering a viable option with desirable long-term outcomes. Technique Description: A partial-thickness quadriceps tendon autograft was harvested, the remnant PCL stump was debrided, and a reamer was used to drill the all-inside tibial tunnel for traction suture passage. An accessory low anterolateral portal was utilized to drill the femoral tunnel for passage of the femoral traction stitch. Traction sutures were withdrawn, and the graft was passed into the tibia, docked into the femur, fixated with an interference screw, and tensioned over the tibial button. A medial meniscal ramp tear was also identified and repaired in all-inside fashion with a 90° SutureLasso, polydioxanone suture (PDS), and suturetape via standard arthroscopic knot tying. Following the procedure, the patient began a PCL reconstruction rehabilitation protocol with a PCL rebound brace. Due to the meniscal ramp repair, toe touch weightbearing with the knee in extension during ambulation was completed for 6 weeks. Physical therapy (PT) focused on early quadriceps and patellar mobilization as well as active-assisted range of motion exercises. Results: At 6 months postoperation, the patient continued to progress in PT without major concerns. A full recovery and return to sport are expected approximately 9 to 12 months after surgery, as is consistent with the standard protocol. Discussion/Conclusion: This study describes the treatment of chronic PCL with concomitant meniscal ramp tear in a division I athlete. Further adoption of PCL reconstruction utilizing quadriceps autograft, even in the context of concomitant ligamentous or meniscal reconstruction, such as medial meniscal ramp repair, will aid in the widespread treatment of PCL injuries. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication. [ABSTRACT FROM AUTHOR]

Background: Platelet-rich plasma (PRP) and bone marrow aspirate concentrate (BMAC) have gained popularity in recent years as biologic approaches to potentially augment healing after meniscus repair. There have been few studies comparing outcomes in patients undergoing meniscus repair with versus without biologic augmentation and, furthermore, little clarity on the role of biologic augmentation for meniscus repairs performed with concomitant anterior cruciate ligament reconstruction (ACLR). Purpose: To determine the association of BMAC or PRP augmentation with revision surgery after both isolated meniscus repair and meniscus repair performed concomitantly with ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: The PearlDiver Mariner dataset was queried to identify all patients who underwent primary meniscus repair, both with and without concomitant ACLR, and who received ipsilateral BMAC or PRP at the time of surgery. Patients who underwent similar surgery but without BMAC or PRP augmentation were then identified and matched in a 5:1 ratio according to age, sex, body mass index, and various comorbidities to 3 separate BMAC/PRP augmentation groups: overall cohort (with and without ACLR), repair with concomitant ACLR, and isolated repair. The primary outcome was revision meniscus surgery (meniscectomy or revision meniscus repair). Results: Overall, 3420 patients (570 with BMAC/PRP augmentation; 2850 matched controls without augmentation) were included. There were no significant differences in the reported demographics or comorbidities between any of the BMAC/PRP groups and their respective matched controls (P >.05 for all comparisons). There was no difference in revision rate between BMAC/PRP-augmented isolated meniscus repairs and matched controls (P =.235). Patients who underwent BMAC/PRP-augmented meniscus repair with concomitant ACLR experienced a significantly lower incidence of revision surgery compared with matched controls without BMAC/PRP augmentation (5.2% vs 7.9% respectively; odds ratio, 0.41; 95% CI, 0.27-0.63; P <.001), but the number of revisions was relatively small. Conclusion: There was no association between BMAC or PRP augmentation and the incidence of revision surgery after isolated primary meniscus repair. There was a statistically significant decrease in the rate of revision meniscus surgery when BMAC or PRP was used to augment meniscus repairs in the setting of concurrent ACLR; however, the overall revision rates were small. [ABSTRACT FROM AUTHOR]

Background: Performing meniscal repair with anterior cruciate ligament reconstruction (ACLR) has been shown to contribute to the long-term preservation of knee health and gait biomechanics. Purpose: To evaluate the role of meniscal repair in the performance of semiprofessional soccer players who returned to sport after ACLR. Study Design: Case series; Level of evidence, 4. Methods: This study included 51 male soccer players (mean ± SD age, 28.82 ± 5.33 years) who underwent ACLR at a single institution between July 2018 and July 2019. The players were divided into 3 groups according to surgery type: ACLR only (n = 30), ACLR with lateral meniscal repair (n = 9), and ACLR with medial meniscal repair (n = 12). Outcomes were evaluated through clinical examination, self-reported health questionnaires (Cincinnati Knee Rating System, Tegner activity score, Tegner Lysholm Knee Scoring Scale, Tampa Scale of Kinesiophobia, and ACL–Return to Sport After Injury), and biomechanical performance evaluations (balance, strength, coordination, and symmetry tests). Parametric and nonparametric tests were carried out for multiple comparisons. Results: The mean ± SD follow-up time was 20.75 ± 9.38 months. Although no significant differences emerged in clinical and self-reported health status, almost all the physical parameters tested resulted in lower performance in players treated with ACLR and meniscal repair. Moreover, patients with ACLR with lateral meniscal repair reported higher pain and fear of reinjury, with lower outcomes in terms of strength, symmetry, and coordination as compared with the other 2 groups. Balance abilities were significantly affected in players who underwent meniscal repair as compared with those who underwent ACLR only. Conclusion: The findings showed that biomechanical performance measures and fear of reinjury were significantly worse in soccer players with associated meniscal repair at a minimum 1-year follow-up, especially in those with a lateral meniscal tear. [ABSTRACT FROM AUTHOR]

Background: Meniscus root tears are associated with chondral injury, early degenerative change, and a high conversion rate to total knee arthroplasty. It is well-established that meniscus root tears lead to decreased femorotibial contact area, increased peak contact pressures, and increased stress on the articular cartilage. Purpose: To evaluate the biomechanical characteristics of the all-inside meniscus root repair procedure and compare it with the previously described transtibial technique. Study Design: Controlled laboratory study. Methods: Nine paired cadaveric knees were prepared by removing skin, subcutaneous tissues, quadriceps muscles, patella, and patellar tendon, while leaving the capsule in place. Pressure-mapping sensors were inserted, and specimens underwent compressive loading to obtain peak pressures, mean pressures, and femorotibial contact area in the medial and lateral compartments. Tests were performed as static compression tests with the knee locked at 0° of flexion. Compression testing was performed in 3 states: meniscus intact, meniscus root cut, and after meniscus root repair with an all-inside repair technique. Additionally, testing was completed on 9 pairs of cadaveric knees to compare stiffness and maximal load to failure between the all-inside and transtibial meniscus root repair techniques. Results: In the medial compartment, there were significant increases in median peak pressures and median mean pressures in the root cut state as compared with the intact state (+636 kPA [95% CI, 246 to 1026] and +190 kPA [95% CI, 49 to 330], respectively). All-inside meniscus root repair restored median peak pressures and median mean pressures to approach those of the intact meniscus (+311 kPA [95% CI, –79 to 701] and +137 kPA [95% CI, –3 to 277]). In the lateral compartment, there were also significant increases in median peak pressures and median mean pressures in the root cut state as compared with the intact state (+718 kPA [95% CI, 246 to 1191] and +203 kPA [95% CI, 51 to 355]). All-inside meniscus root repair restored median peak pressures and median mean pressures such that they were not significantly different from the intact state (+322 kPA [95% CI, –150 to 795] and +18 kPA [95% CI, –134 to 171]). There was no difference between repair techniques regarding load to failure (P =.896). Transtibial meniscus root repair had significantly more stiffness (mean ± SD, 24.8 ± 9.3 N/mm) as compared with the all-inside meniscus root repair technique (13.6 ± 3.8 N/mm, P =.015). Conclusion: All-inside meniscus root repair reduced median peak and mean pressures to those of the native intact meniscus with the knee in extension in the cadaveric model. When compared with a transtibial meniscus root repair technique, all-inside repair demonstrated decreased stiffness and a similar load to failure. Clinical Relevance: All-inside meniscus root repair restored mean and peak femorotibial pressures to those of the intact meniscus. Additionally, it offers a technically easier technique for management of meniscus root tears. [ABSTRACT FROM AUTHOR]

Background: The effect of a concurrent cartilage procedure in lateral meniscal allograft transplantation (MAT) in patients with bipolar cartilage lesions (high-grade lesions on both the femoral and the tibial side) is not well studied. An objective evaluation of graft status after MAT and a concurrent cartilage procedure has not been reported. Purpose: To investigate the effect of concurrent cartilage procedures and lateral MAT on objective and clinical outcomes, including survival, in patients with bipolar cartilage lesions. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 149 patients with high-grade (International Cartilage Regeneration & Joint Preservation Society grade 3 or 4) cartilage lesions were enrolled and assigned to 1 of 3 groups based on the cartilage procedure and cartilage status at the time of MAT. Femoral cartilage procedures (microfracture, n = 18; osteochondral autograft transfer, n = 13) and lateral MAT were performed in 31 patients with bipolar cartilage lesions (cartilage procedure group). Another 70 patients with bipolar lesions underwent only lateral MAT without cartilage procedure (bipolar lesion group). The remaining 48 patients, who had high-grade lesions only on the tibial side and underwent lateral MAT without a cartilage procedure, were selected as a control group (unipolar lesion group). Anatomic survival was objectively assessed by follow-up magnetic resonance imaging and second-look arthroscopy. Clinical survivorship was determined with a Lysholm score <65 or need for additional surgery, such as revision MAT. Results: The mean Lysholm score improved from 67.2 ± 15.9 preoperatively to 86.7 ± 11.1 with a mean follow-up of 78.0 ± 51.2 months (P <.001). The postoperative scores were not significantly different between the 3 groups. The estimated 5-year anatomic survival rate in the cartilage procedure group (86.7%) was higher than that in the bipolar lesion group (65.0%; P =.043) but comparable with that in the unipolar lesion group (90.2%; P =.572). The estimated 5-year clinical survival rates were not significantly different between the groups (P =.187). Conclusion: A concurrent femoral cartilage procedure improved the anatomic survival rate in patients with bipolar chondral lesions who underwent lateral MAT. This finding suggests that the cartilage procedure is an effective treatment choice and may improve the status of an allograft after lateral MAT for patients with bipolar cartilage lesions. [ABSTRACT FROM AUTHOR]

Background: Preoperative body mass index (BMI) is one of the correctable factors before surgery. Few studies have investigated the effect of BMI on the survivorship of lateral meniscal allograft transplantation (MAT). Hypothesis: Patients with a high BMI have inferior survivorship after lateral MAT when compared with those with a normal BMI. Study Design: Cohort study; Level of evidence, 3. Methods: Overall, 306 consecutive patients who underwent lateral MAT were retrospectively reviewed. According to the classification criteria of the World Health Organization, patients were split into 2 groups: normal weight (BMI <25.0) and overweight (BMI ≥25.0). There were 104 patients (34.0%) allocated into the overweight group. Given the demographic heterogeneity between the groups, propensity score matching was performed. Before and after propensity score matching, the anatomic and clinical survival rates of the 2 groups were compared by Kaplan-Meier survival analysis. Anatomic failure was defined as a tear covering >50% of the allograft or unstable peripheral rim on follow-up magnetic resonance imaging and second-look arthroscopy. Clinical failure was defined as a Lysholm score <65 or need for additional surgery, such as revision MAT. Results: For all patients, the mean ± SD follow-up period was 6.9 ± 4.2 years. The mean BMI of the overweight and normal weight groups was 27.8 ± 2.6 and 22.0 ± 1.9, respectively. The mean Lysholm scores at the last follow-up were not significantly different between the groups. However, the anatomic survival rate in the overweight group (77.9%) was significantly lower than that in the normal weight group (90.1%) (P <.001). The clinical survival rate (82.7%) in the overweight group was significantly lower than that in the normal weight group (95.0%) (P <.001). After propensity score matching for patient characteristics, which left 87 patients per group, the anatomic and clinical survival rates were significantly lower in the overweight group. Conclusion: Preoperative high BMI was associated with inferior anatomic and clinical survival rates. The results of the current study suggest that weight loss before lateral MAT may be required in overweight patients for the improvement of anatomic and clinical survival rates. [ABSTRACT FROM AUTHOR]

Objectives: Repair of posterior medial meniscus root (PMMR) tears demonstrates favorable patient outcomes and may prevent rapid progression of knee osteoarthritis, however, there is a paucity of data in literature regarding prognostic factors affecting postoperative outcomes. The medial meniscus plays an important role in the knee biomechanically by increasing tibiofemoral contact area and decreasing peak tibiofemoral contact pressures. Few studies exist that examine preoperative knee magnetic resonance imaging (MRI) findings and patient reported outcome measures (PROMs) following PMMR repair. Semi-quantitative MRI evaluation can offer improved detection of degenerative pathology. Identifying specific factors that may predict surgical outcomes is important when considering PMMR repair, as some patients with more advanced degenerative joint disease may benefit from consideration for knee arthroplasty instead of joint preservation with meniscus repair surgery. The purpose of this study was to identify factors on preoperative MRI that may predict postoperative outcomes following PMMR repair. We hypothesize that patients with worse knee overall quality would have worse postoperative PRO scores. Methods: Between 2012 and 2020, patients who underwent posterior medial meniscus root repair at a tertiary referral academic center by fellowship trained sports medicine surgeons were retrospectively identified, recruited, and enrolled in the study. Institutional review board approval and informed consent was obtained. Inclusion criteria included patients ages 18-70, posterior medial meniscus root repair through transtibial fixation technique, minimum two years postoperative follow-up, and a preoperative knee MRI. Exclusion criteria included prior ipsilateral knee meniscus or ligamentous injury, additional ipsilateral knee injury requiring surgery, and conversion to knee arthroplasty. Visual Analog Scale (VAS) pain and PRO surveys including Patient Reported Outcome Measures Information System Physical Function (PROMIS-PF) Computer Adaptive Test, Lysholm Knee Score, Knee Osteoarthritis and Injury Outcome Score (KOOS) with 5 sub-sections, were collected at minimum 2-years postoperative. Patient Acceptable State Score (PASS) values from a prior meniscus study were utilized to identify patients that met PASS for the KOOS subsections. A fellowship-trained musculoskeletal radiologist reviewed preoperative MRIs and calculated Whole Organ Magnetic Resonance Imaging Scores (WORMS) for meniscus, cartilage, bone marrow edema pattern (BMEP) in 6 knee locations as well as effusion/synovitis and meniscal extrusion. Radiographs were scored with Kellgren-Lawrence (KL) scores to assess presence and severity of osteoarthritis. Statistical analysis was performed with Stata (StataCorp) using two sample T-tests, Mann-Whitney, and Fisher's exact test for categorical variables. Significance was defined as p<0.05. Results: We evaluated 29 knees (22 female patients) with a mean age at surgery of 52.3±9.9 years, body mass index of 27.6±5.6 kg/m2, and at a mean follow-up of 59.6 months ± 26.5. median KL grade 2, and 44.8% with meniscal extrusion. Pain scores decreased significantly from before surgery to final follow-up (p<0.001), and the percentage of patients meeting PASS ranged from 44.8% for KOOS-Sport subscale to 72.4% for KOOS-Pain and KOOS-Quality of Life subscales (Table 1). There were 10 patients with medial tibial BMEP on pre-operative MRI and 19 with no medial tibial BMEP (Table 2). Patients with medial tibia BMEP had significantly lower Lysholm Knee Score (p=0.037), KOOS-Symptoms (p=0.028), and KOOS-QOL (p=0.029) (Figure 1). There were no significant differences in demographics between those with and without medial tibia BMEP. There was no significant difference in PRO scores when comparing those with medial femoral condyle BMEP, cartilage quality in any of the knee regions, or presence of meniscus extrusion. Conclusions: We observed that patients with medial tibia BMEP at baseline on their preoperative MRI had inferior PROMs for Lysholm Knee Score, KOOS Symptoms, and KOOS-QOL after PMMR repair compared to those without medial tibia BMEP. The presence of medial tibial BMEP could represent underlying damage that may not be evident in the cartilage itself, given most medial tibia cartilage was normal on MRI and cartilage quality was not a significant discriminant for outcomes. The presence of meniscus extrusion did not correlate with patient outcomes either. Limitations of this study include only VAS-Pain score as a pre-operative measure. Multivariate analysis was not possible due to the sample size available. A strength of this study is the mean follow up of approximately 5 years and preoperative MRI data on all patients. Posterior medial meniscus root tears are generally treated with surgical repair due to increased risk of progression to arthritis, however, some patients continue to have symptoms after repair. Our results show that patients with medial tibial BMEP on their preoperative MRI have worse PRO scores after posterior medial meniscus root repair, which can help surgeons better counsel patients towards optimal treatment options. In conclusion, the presence of medial tibia BMEP on preoperative MRI was a marker for inferior patient outcomes for Lysholm Knee Score, KOOS Symptoms, and QOL at minimum two years postoperative following posterior medial meniscus root repair. [ABSTRACT FROM AUTHOR]

Objectives: Meniscal injuries are among the most common orthopedic injuries in the United States. Radial meniscus tears were historically treated with partial meniscectomy, often leading to poor outcomes. Radial tear repair preserves meniscal tissue, may delay knee degeneration, and leads to better long-term outcomes. Repair techniques for radial tears vary and should be evaluated for differences in biomechanical properties and failure mechanisms. All-inside, meniscus-based suture repairs have shorter operating times, minimize risk of nerve injury, and are increasingly possible with novel devices. Our objective was to evaluate the strength based on load-to-failure of four all-inside meniscus-based repair techniques for radial tears in human cadaveric lateral menisci. We chose two techniques that bridged the tear directly - the Double Vertical (DV, Figure 1) and Double Vertical Cross (DVX, Figure 2). We chose two other techniques that added horizontal reinforcing stitches to engage the bridging stitches - the All-inside Rebar (AR, Figure 3) and our novel Oblique Box (OB, Figure 4). We hypothesized that AR and OB would have higher load to failure than DV and DVX. Methods: 36 fresh-frozen human adult lateral menisci were randomized into four groups of nine. Dissection, repair, and testing were completed one meniscus at a time to minimize the time period from thawing to testing. Each meniscus was dissected from its tibial bone block, and a complete radial tear was created at the midbody of the meniscus. Suture repairs were performed using 2-0 braided suture and a straight needle. Menisci were repaired using the DV, DVX, AR, and OB techniques with meniscus- based suturing to simulate the all-inside, meniscus-based approach. All suture dimensions were standardized as indicated on Figures 1-4, and all knots were tied on the superior surface of the menisci. The suture patterns for all repair types used loops that passed above the superior and below the inferior surfaces of the meniscus. The DV repair used two sutures in loops perpendicular to the tear. DVX used two sutures in loops that crossed over the tear. AR used two sutures in loops parallel to the tear acting as reinforcing rebar and two bridging sutures perpendicular to the tear and outside the rebar sutures. OB used two sutures to create a trapezoidal reinforcing box on either side of the tear and two bridging sutures in loops perpendicular to the tear and inside the box. The repaired menisci were loaded on an Instron 5944 test frame with 2 kN load cell using custom clamps. They underwent cyclic loading of 5-30 N for 500 cycles at 10 mm/min, a 30-minute resting period, and a single trial of load-to-failure at 10 mm/min. The ultimate load at failure was analyzed via one-way ANOVA with Tukey's test for pairwise comparisons and significance set at p<0.05. Results: Failure occurred due to suture cutout in all specimens. Repair constructs that lacked a reinforcing-type suture (DV and DVX) cut through or "cheese-wired" at lower loads than repairs with reinforcing sutures (AR and OB). Mean ± standard deviation ultimate load values for each repair group were 60 N ± 24.5 for DV, 58 N ± 17.4 for DVX, 168 N ± 33.9 for AR, and 105 N ± 9.0 for OB. The ultimate load for all repair techniques were significantly different from each other by Tukey's test with the exception of the DV and DVX comparison. These results show that reinforcing vertical suture meniscus repairs with some type of horizontal suture (e.g. AR or OB) significantly increases ultimate load at failure for all-inside, meniscus-based techniques. Conclusions: In a cadaveric lateral meniscus model, all-inside radial repairs using rebar suture, or horizontal suture reinforcing techniques, had higher ultimate load at failure and reduced risk of "cheese wiring". The AR repair sustained the highest ultimate load at failure, nearly 3x stronger than the two non-reinforcing type repair constructs. These data may provide useful information for surgeons during repair to radial meniscus tears. Future biomechanical study should compare all-inside vs. inside-out repairs to maximize patient outcomes. Cross reference of repair patterns with clinical outcomes using the prospective registry data may support optimal surgical techniques to improve meniscus repair outcomes. [ABSTRACT FROM AUTHOR]

Objectives: Meniscal injuries occur in as many as 1% of active people, and while outcomes for tears at the posterior medial meniscal root (PMMR) are well cited, the risk factors for injury have room for greater understanding. Incidence of disruption to the meniscotibial ligament (MTL) is correlated to occurrence of PMMR tears, suggesting that disruption to the MTL may increase forces at the PMMR and put the PMMR at greater risk of injury. The effect of an MTL disruption and repair on three-dimensional forces at the PMMR is unknown. The purpose of this study was to determine if MTL insufficiency alters forces at the PMMR., if a tenodesis procedure can restore PMMR forces to that of an MTL intact state, and to determine how knee flexion angle impacts PMMR root forces in the MTL intact and cut states. We hypothesize that all shear forces will increase following MTL disruption. Methods: Ten fresh-frozen cadaveric knees (Average age: 53.2 years) were tested in three conditions (Intact, MTL Cut, MTL Tenodesis). Specimens were dissected down to the knee capsule with ligaments intact. A 3D load cell construct (Figure 1) was installed inside the tibia such that 3D forces of the PMMR could be measured when the joint was loaded. Each specimen was mounted to a materials testing machine (Instron) via a custom fixture that allowed the specimen flexion angle to be changed in 30 degree increments. The specimen was first loaded to 500 N of compression with 0 N-m of torque, then to 5 N-m of internal torque with 50 N of compression, and finally to 5 N-m of external torque with 50 N of compression. 3D forces at the PMMR were recorded for all loading sequences, and the process was repeated for each flexion angle (0°, 30°, 60°, and 90°). PMMR forces along each axis (compression- tension, anterior-posterior shear, and medial-lateral shear) were compared across MTL testing states across flexion angles using linear mixed modelling. Results: When the joint was loaded in compression, MTL Cut state significantly increased compression of the PMMR (p = 0.0368), and the Tenodesis state did not significantly restore tension-compression forces of the PMMR (Intact → Tenodesis: p = 0.008)(Figure 1). When the joint was loaded in external rotation, the MTL Cut State significantly increased compression (p < 0.0001), significantly decreased anterior shear (p = 0.0003), and, in high flexion angles, significantly decreased ML shear forces of the PMMR (Figure 1). The Tenodesis state did not significantly restore tension-compression (Intact → Tenodesis: p < 0.0001) or AP forces (Intact → Tenodesis: p = 0.0002) of the PMMR (Figure 1). Conclusions: The key finding of this study is that MTL disruption increases compression forces and decreases AP shear forces seen at the root when the joint is loaded in compression and external rotation. These findings indicate that the intact MTL protects the PMMR from compression and shear loads during movements where the joint is loaded in compression and external rotation, movements that are clinically reported to put the knee joint at risk of PMMR injury. The authors believe these relationships are observed because the MTL may play a role in maintaining meniscal hoop stresses, which converts joint compression loads into tension and shear forces along the meniscal attachment points. When the MTL is disrupted, the other meniscal attachment points, the PMMR included, see elevated compression loads as a result. This is the first study to measure 3D forces at the PMMR, a necessary capability to assess PMMR injury risk. It is notable that the tenodesis procedure performed in this study did not restore PMMR forces. Future studies should develop improved centralization or tenodesis procedures to better restore PMMR forces and decrease likelihood for PMMR injury after MTL disruption. [ABSTRACT FROM AUTHOR]

Background: Medial meniscus posterior root tears (MMPRTs) disrupt the integrity and hoop tension of the meniscus, leading to cartilage degeneration and accelerated osteoarthritis (OA) progression. The management of patients with MMPRT is controversial, and the efficacy of different treatment options is unclear. Purpose: To compare the clinical, radiographic, and magnetic resonance imaging (MRI) outcomes of patients with MMPRT between trans–posterior cruciate ligament (trans-PCL) all-inside repair and partial meniscectomy. Study Design: Cohort study; Level of evidence, 3. Methods: We identified patients with MMPRT who underwent trans-PCL all-inside repair (group AR) or partial meniscectomy (group PM) between 2015 and 2019 at a single institution. The trans-PCL all-inside repair was performed by suturing the torn meniscus root to the PCL fibers. Patient-reported outcomes as well as radiographic and MRI outcomes were collected at baseline and final follow-up. Clinical failure was defined as conversion to total knee arthroplasty (TKA), and Kaplan-Meier survival analysis was used to investigate the survival rates of patients with different surgical procedures. Results: Included were 29 patients in group AR and 31 patients in group PM (mean age, 62.69 and 60.68 years, respectively; mean follow-up, 2.91 ± 1.33 and 3.45 ± 1.50 years, respectively). There were no differences in baseline patient characteristics between the groups. All patient-reported outcome scores improved significantly in both groups at the final follow-up. When we compared final outcomes between the groups, group AR had less joint space narrowing (P =.010), less Kellgren-Lawrence OA grade progression (P =.002), and less medial meniscal extrusion (MME; P =.002) than group PM. In addition, group AR showed less progression of bone marrow lesions and cartilage lesions (P <.05) than group PM. The rate of conversion to TKA was 6.90% in group AR and 29.0% in group PM. The 5-year survival rates in the AR and PM groups were 82.6% and 59.8%, respectively (P =.153). Conclusion: Trans-PCL all-inside repair for MMPRTs was associated with greater improvement in clinical function, better radiographic results, less MME and cartilage degeneration, and a lower rate of subsequent TKA compared with partial meniscectomy. [ABSTRACT FROM AUTHOR]

Background: In-office needle arthroscopy (IONA) has been described as a diagnostic alternative to magnetic resonance imaging (MRI) for intra-articular pathology. However, few studies have analyzed its impact on cost and wait times when used as a therapeutic intervention. The purpose of this study was to investigate the impact on cost and wait times associated with offering IONA for partial medial meniscectomy as an alternative to traditional operating room (OR) arthroscopy for patients with irreparable medial meniscus tears on MRI. Methods: Two models were created comparing the existing care pathway (current state) to a proposed future state utilizing IONA. Data sources were accounting data from an academically affiliated hospital in Canada and supplemented with literature values. A Monte Carlo simulation combined with DuPont analysis running 10,000 simulations was conducted to calculate the revenue, expenses, profits, and effect on surgical waitlists (i.e., throughput) between the states. Sensitivity analyses examined the influence of patient preference and revision rates on profit and throughput. Two-sample Student's t test was performed (p <.05). Results: An average of 198 (standard deviation (SD) 31) patients underwent arthroscopic meniscectomy or repair each year from 2016 to 2020. The IONA revision rate was calculated as 20.3%. Compared to the current state, annual expenses in the IONA pathway were significantly reduced ($266,912.68 versus $281,415.23, p <.0001), while improving throughput by 21.2% (3.54%). Sensitivity analysis revealed 10% of patients need to select IONA over traditional OR arthroscopy with the revision rate remaining below 40% for the proposed state profit to be higher than the current state. Conclusions: IONA is a cost-effective alternative to traditional OR arthroscopy in patients undergoing partial medial meniscectomy. The next steps are to assess patients' perceptions of IONA as an alternative to traditional OR arthroscopy, and to carry out clinical trials to determine the efficacy, patient-reported outcome metrics, and complications of IONA. [ABSTRACT FROM AUTHOR]

Meniscal tears are one of the most common knee pathologies, and arthroscopic meniscectomy is a frequently performed procedure. The importance of preserving the meniscus, due to its role in chondroprotection and secondary knee stability, is well-accepted. Meniscal repair techniques have evolved over time from initial open repairs to arthroscopic inside-out and outside-in repairs, and more recently to repairs using all-inside devices. In this article, the authors reviewed the function, anatomy and biomechanics of the meniscus, and discussed the literature to support the argument for repairing meniscal tears. [ABSTRACT FROM AUTHOR]

Background: The presence of a lateral meniscus root tear (LMRT) in patients with an anterior cruciate ligament (ACL) tear makes the knee more unstable and increases the risk of osteoarthritis and osteonecrosis. An all-inside suture repair technique without bone tunnels has been proposed to treat LMRT. Purpose: To compare the 1-year postoperative findings between patients who underwent ACL reconstruction combined with LMRT repair (LMRT group) and patients who underwent isolated ACL reconstruction (control group). Study Design: Cohort study; Level of evidence, 3. Methods: The LMRT group consisted of 19 patients, and the control group consisted of 56 patients. In this study, the authors compared the postoperative magnetic resonance imaging (MRI) findings (meniscal extrusion, ghost sign, and hyperintensity in the tibial plateau beneath the LMRT), functional outcomes (International Knee Documentation Committee [IKDC], Lysholm, and Tegner scores), and reoperation rate between groups. The primary endpoint was analyzed by comparing, in the LMRT group, the 1-sided 97.5% confidence interval (CI) of the mean lateral meniscal extrusion at 1 year to the limit of noninferiority (fixed at 0.51). To take into account imbalanced baseline characteristics between groups, adjusted mean meniscal extrusion (with 1-sided 97.5% CI) was assessed using a linear regression model. Results: The mean follow-up was 12.2 months (range, 7.7-14.7 months) in the control group and 11.5 months (range, 7.1-13.0 months) in the LMRT group (P =.06). For meniscal extrusion, the LMRT group was noninferior to the control group. The mean meniscal extrusion was 2.19 mm (97.5% CI, —infinity to 2.68 mm) in the LMRT group and 2.03 mm (97.5% CI,—infinity to 2.27 mm) in the control group, indicating that the upper boundary of the 1-sided 97.5% CI in the LMRT group was less than the noninferiority threshold of 2.78 (ie, 2.27 mm + 0.51 mm = 2.78 mm). There was a statistically significant difference in the IKDC score between the LMRT and control groups (77.2 ± 8.1 vs 80.3 ± 7.3, respectively; P =.04). There was no between-group difference in the other MRI parameters, the Lysholm and Tegner scores, or the reoperation rate. Conclusion: There was no significant difference in extrusion on MRI or clinical outcomes at 1-year follow-up in patients who underwent ACL reconstruction with all-inside LMRT repair compared with patients who did not have an LMRT. [ABSTRACT FROM AUTHOR]

Background: Discoid lateral meniscus (DLM) has a varied and complex morphology that can be challenging to assess and treat. Preoperative magnetic resonance imaging (MRI) is frequently used for diagnosis and surgical planning; however, it is not known whether surgeons are reliable and accurate in their interpretation of MRI findings when defining the pathomorphology of DLM. Hypothesis: Surgeons experienced in treating DLM are able to reliably interpret DLM pathology using MRI. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: Knee MRI scans from 44 patients (45 knees) were selected from a pool of surgically treated patients with DLM. Five reviewers (fellowship-trained pediatric sports medicine surgeons) performed independent review of each MRI scan using the PRiSM Discoid Meniscus Classification. Inter- and intraobserver reliability of the rating factors—primary (width, height, presence of peripheral instability or tear) and secondary (location of instability or tear, tear type)—was assessed using the Fleiss κ coefficient, designed for multiple readers with nominal variables (fair reliability, 0.21-0.40; moderate, 0.41-0.60; substantial, 0.61-0.80; excellent, 0.81-1.00). Reliability is reported as κ (95% CI). Results: Interobserver reliability in assessing most primary and secondary characteristics ranged from substantial (meniscal width) to moderate (peripheral instability, anterior instability, posterior instability, and posterior tear). Intraobserver reliability for most characteristics ranged from substantial (peripheral instability, presence of tear, anterior instability, posterior instability, and posterior tear) to moderate (meniscal width, anterior tear, and tear type). Notable exceptions were presence of tear, anterior tear, and tear type—all with fair interobserver reliability. Height had poor interobserver reliability and fair intraobserver reliability. Conclusion: Orthopaedic surgeons reliably interpret MRI scans using the PRiSM Discoid Meniscus Classification for the majority of DLM characteristics but vary in their assessment of height and presence and type of tear. MRI evaluation may be helpful to diagnose discoid by width and identify the presence of instability: 2 major factors in the decision to proceed with surgery. Arthroscopic evaluation should be used in conjunction with MRI findings for complete DLM diagnosis. [ABSTRACT FROM AUTHOR]

Background: Medial opening-wedge high tibial osteotomy (MOWHTO) reduces contact stress by altering the weightbearing axis from the medial to the lateral compartment, relieves knee pain, and slows the progression of osteoarthritis. Purpose/Hypothesis: To evaluate whether the volume of the medial meniscus affects outcomes after MOWHTO. It was hypothesized that reduced medial meniscal volume would be associated with worse midterm clinical and radiographic outcomes. Study Design: Cohort study; Level of evidence, 3. Methods: Included were 59 patients who underwent MOWHTO and had ≥4 years of follow-up data. The mean follow-up period was 66.5 ± 15.1 months (range, 48-110 months). The cohort was classified into 3 groups according to the status of the medial meniscus on arthroscopic examination before osteotomy: no meniscal tear, degenerative tear leading to partial meniscectomy, and degenerative tear leading to subtotal meniscectomy. The Hospital for Special Surgery score and Knee Society objective and functional scores were compared among the groups at 2 time points (preoperative and latest follow-up), and the medial joint space width (JSW) was compared among the groups at 3 time points (preoperative, 1 year postoperative, and latest follow-up). Results: Overall, 9 patients had no meniscal tear, 20 patients underwent partial meniscectomy, and 30 patients underwent subtotal meniscectomy. The clinical scores improved significantly from preoperatively to the latest follow-up (P ≤.001 for all), with no significant difference among the groups. Post hoc analysis indicated that at the latest follow-up, JSW was significantly lower in the subtotal meniscectomy group compared with the no-tear group on both 45° of flexion posterior-anterior (2.5 ± 1.3 vs 3.9 ± 1.8 mm; P =.004) and anterior-posterior (3.4 ± 1.1 vs 4.5 ± 0.9 mm; P =.011) radiographs. Conclusion: Subtotal meniscectomy of the medial meniscus performed during arthroscopic examination with MOWHTO was associated with decreased JSW at midterm follow-up. Efforts should be made to preserve the medial meniscus as much as possible during MOWHTO. [ABSTRACT FROM AUTHOR]

Background: The discoid medial meniscus is a rare congenital anomaly of the knee. The literature is limited to small case series. Purpose/Hypothesis: Our purpose is to report the clinical manifestations and operative treatments of discoid medial menisci in children from multiple centers in North America. We hypothesized that symptoms and signs, arthroscopic findings, surgical treatments, and outcomes are similar to those for symptomatic discoid lateral menisci. Study Design: Case series; Level of evidence, 4. Methods: A retrospective review identified patients with a diagnosed discoid medial meniscus confirmed at surgery across 8 children's hospitals between January 2000 and June 2021. The literature on discoid lateral menisci was reviewed and summarized for comparison. Results: A total of 21 patients (9 female, 12 male) with 22 discoid medial menisci were identified. The mean ± SD age at the time of diagnosis was 12.8 ± 3.8 years. The most common symptoms and signs were locking and/or clunking, present in 12 of 22 knees (55%), similar to that reported in patients with discoid lateral menisci. Twelve discoid medial menisci were complete (55%); 8, incomplete (36%); and 2, indeterminate (9%). Tears were present in 13 knees, most commonly horizontal cleavage (54%). Five discoid medial menisci were unstable (23%): 3 for posterior tears and 2 for rim insufficiency. All 22 knees underwent arthroscopic saucerization, and of the 13 torn menisci, 7 (54%) were repaired. The median follow-up was 24 months (range, 2-82 months). Four knees underwent reoperation. All knees that required reoperation had undergone repair for a posteriorly located tear. There was a significant association between operative repair and need for reoperation (P =.0048). High rates of peripheral instability were also noted in case series of patients with discoid lateral menisci. Conclusion: Patient presentations and treatments for those with discoid medial menisci were similar to those reported for patients with discoid lateral menisci. Knees with discoid medial menisci also demonstrated instability attributed to peripheral insufficiency and posterior tears. Tears were present in over half of knees with discoid medial menisci, and reoperation was more common in knees that underwent repair of tears than those without repair. [ABSTRACT FROM AUTHOR]