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Purpose: To perform a systematic review of the literature to evaluate (1) activity level and knee function, (2) reoperation and failure rates, and (3) risk factors for reoperation and failure of autologous osteochondral transfer (AOT) at long-term follow-up., Methods: A comprehensive review of the long-term outcomes of AOT was performed. Studies reported on activity-based outcomes (Tegner Activity Scale) and clinical outcomes (Lysholm score and International Knee Documentation Committee score). Reoperation and failure rates as defined by the publishing authors were recorded for each study. Modified Coleman Methodology Scores were calculated to assess study methodological quality., Results: Twelve studies with a total of 495 patients and an average age of 32.5 years at the time of surgery and a mean follow-up of 15.1 years (range, 10.4-18.0 years) were included. The mean defect size was 3.2 cm 2 (range, 1.9-6.9 cm 2 ). The mean duration of symptoms before surgery was 5.1 years. Return to sport rates ranged from 86% to 100%. Conversion to arthroplasty rates ranged from 0% to 16%. The average preoperative International Knee Documentation Committee scores ranged from 32.9 to 36.8, and the average postoperative International Knee Documentation Committee scores at final follow-up ranged from 66.3 to 77.3. The average preoperative Lysholm scores ranged from 44.5 to 56.0 and the average postoperative Lysholm scores ranged from 70.0 to 96.5. The average preoperative Tegner scores ranged from 2.5 to 3.0, and the average postoperative scores ranged from 4.1 to 7.0., Conclusions: AOT of the knee resulted in high rates of return to sport with correspondingly low rates of conversion to arthroplasty at long-term follow-up. In addition, AOT demonstrated significant improvements in long-term patient-reported outcomes from baseline., Level of Evidence: Level IV, systematic review of Level I-IV studies., Competing Interests: Disclosures The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: J.F.O. reports paid consultant for Kaliber.ai; M.H. reports paid consultant for DJO–Enovis, Moximed, and Vericel; publishing royalties, financial or material support from Elsevier; and editorial or governing board for Journal of Cartilage and Joint Preservation. C.L.C. reports paid consultant for Arthrex; research support from Major League Baseball; and publishing royalties, financial or material support from Springer. A.J.K. reports research support from Aesculap/B. Braun; editorial or governing board for American Journal of Sports Medicine; IP royalties, paid consultant for Arthrex; board or committee member for Arthroscopy Association of North America and International Cartilage Repair Society; and editorial or governing board for Springer. All other authors (M.E.D., F.W.F., J.A.P., A.P., L.H.) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate and compare isokinetic knee muscle (extension and flexion) strength, single-leg hop (SLH) test performance, anterior knee laxity, subjective knee function, and the 2-year revision surgery risk between patients who underwent anterior cruciate ligament reconstruction (ACLR) with semitendinosus tendon (ST) autografts and patients who underwent ACLR with ST and gracilis tendon (ST-G) autografts., Methods: We identified patients aged 16 years or older who underwent primary ACLR with hamstring tendon autografts at our institution from January 2005 to December 2020 and had no associated ligament injuries. Isokinetic knee muscle strength and SLH test performance were assessed 6 months postoperatively. Anterior knee laxity (KT-1000 arthrometer, 134 N) was assessed preoperatively and 6 months postoperatively. The Knee Injury and Osteoarthritis Outcome Score (KOOS) was collected preoperatively and 1 and 2 years postoperatively. Patients who underwent revision ACLR at any institution in Sweden within 2 years of primary surgery were identified through the Swedish National Knee Ligament Registry., Results: A total of 6,974 patients (5,479 with ST and 1,495 with ST-G) were included. There were no significant differences in extension and flexion strength or SLH test performance between the groups. Preoperatively, there was no significant difference in knee laxity between the ST and ST-G groups. Postoperatively, the ST-G group had significantly increased mean side-to-side (STS) laxity (2.1 ± 2.3 mm vs 1.7 ± 2.2 mm, P < .001) and showed a trend toward increased STS laxity according to the International Knee Documentation Committee form, with significantly fewer patients with STS laxity of 2 mm or less (58.4% vs 65.8%) and significantly more patients with STS laxity between 3 and 5 mm (35.0% vs 29.9%) or greater than 5 mm (6.6% vs 4.3%) (P < .001). The only significant difference in subjective knee function was for the KOOS Quality of Life subscale score in favor of the ST group preoperatively (37.3 ± 21.4 vs 35.1 ± 19.9, P = .001). No other significant differences between the groups were found preoperatively and 1 and 2 years postoperatively for any of the KOOS subscales. The overall revision ACLR rate within 2 years of primary surgery was 2.0% (138 of 6,974 patients). The revision ACLR risk in the ST-G group (1.7%, 25 of 1,495 patients) was not significantly different from that in the ST group (2.1%, 113 of 5,479 patients) (hazard ratio, 0.80; 95% confidence interval, 0.50-1.24; P = .32)., Conclusions: The addition of the gracilis tendon to an ST autograft was not associated with knee muscle strength, SLH test performance, subjective knee function, or the risk of revision surgery after ACLR., Level of Evidence: Level III, retrospective comparative study., Competing Interests: Disclosures The authors report no conflicts of interest in the authorship and publication of this article. Full ICMJE author disclosure forms are available for this article online, as supplementary material., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Purpose: (1) To determine the effect of concomitant ipsilateral knee pain (IKP) on short-term outcomes after hip arthroscopic treatment of femoroacetabular impingement syndrome (FAIS) and (2) to determine whether IKP would improve with surgery., Methods: Data between September 2021 and May 2022 were reviewed. Patients with a diagnosis of FAIS who underwent hip arthroscopy with a minimum of 1-year follow-up were included. The exclusion criteria were prior ipsilateral hip or knee surgery, hip Tönnis grade greater than 1, knee Kellgren-Lawrence grade greater than 2, hip conditions (avascular necrosis, Legg-Calvé-Perthes disease, pigmented villonodular synovitis, osteoid osteoma, synovial chondromatosis, and developmental dysplasia of the hip), and spine diseases. All patients underwent knee magnetic resonance imaging preoperatively. Preoperative and short-term (1-year) patient-reported outcomes were collected, consisting of the Hip Sports Activity Scale score, weekly sports participation, modified Harris Hip Score (mHHS), 12-component International Hip Outcome Tool (iHOT-12) score, and visual analog pain scale (VAS) scores for the hip and the ipsilateral knee. The percentages of patients achieving the minimal clinically important difference and patient acceptable symptom state (PASS) for the mHHS and iHOT-12 score were calculated. Multivariate regression analysis was performed to determine the effect of IKP severity on postoperative outcomes. Subgroup analysis was performed between patients with IKP alleviation and those without IKP alleviation., Results: Among the 107 patients included, 47 presented with preoperative IKP. Compared with patients without IKP, the IKP cohort had comparable knee structural abnormalities (all with P > .05). Still, the IKP cohort showed inferior preoperative values for the mHHS (P = .003), iHOT-12 score (P = .016), hip VAS score (P = .001), and weekly sports participation (P = .039). Postoperatively, the IKP cohort had a lower mHHS (P = .046), lower iHOT-12 score (P = .037), and lower hip VAS score (P = .003) and were less likely to achieve the PASS for the mHHS (P = .021) and iHOT-12 score (P = .049). Patients with higher knee VAS scores were less likely to achieve the PASS for the mHHS (odds ratio, 0.61; P = .023). Within the IKP group, the knee VAS score improved from 2.3 to 1.0 (P < .001). Patients with alleviated IKP showed superior postoperative iHOT-12 scores (P = .038) compared with patients with persistent IKP., Conclusions: Concomitant IKP at baseline negatively affected preoperative status and short-term clinical outcomes after arthroscopic treatment of FAIS. Patients with IKP were less likely to meet clinical thresholds. Most patients achieved IKP alleviation postoperatively, which was associated with superior clinical outcomes., Level of Evidence: Level III, retrospective cohort study., Competing Interests: Disclosures The authors report no conflicts of interest in the authorship and publication of this article. Full ICMJE author disclosure forms are available for this article online, as supplementary material., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To simulate the effect of supratuberosity tibial anterior closing-wedge osteotomy (ACWO) in knees with posterior tibial slope (PTS) ≥12° on patellar height when aiming for a target PTS of 5°., Methods: The authors retrospectively reviewed true lateral radiographs of the knees of skeletally mature patients scheduled for primary anterior cruciate ligament reconstruction and included all knees with excessive PTS (≥12°). Coordinates of 11 landmarks were digitized to calculate patellar height (Caton-Deschamps index, CDI) and mid-shaft posterior tibial slope (mPTS). The change in patellar height following a simulated supratuberosity ACWO was calculated and compared for knees with patella norma versus alta. A linear univariable regression model predicted the effect of change in mPTS on CDI., Results: In the final cohort of 83 patients, a simulated supratuberosity ACWO increased CDI from 1.13 (range, 0.73-1.74) to 1.29 (range, 0.84-1.91; P < .001). In 56 patients with patella norma, a simulated supratuberosity ACWO increased CDI from 1.02 (range, 0.73-1.19) to 1.18 (range, 0.84-1.41; P < .001), whereas in patients with patella alta, a simulated supratuberosity ACWO increased CDI from 1.33 (range, 1.20-1.74) to 1.52 (range, 1.36-1.91; P < .001). The linear regression model revealed that a 1° decrease in mPTS increased CDI by 0.02., Conclusions: Simulation of a supratuberosity ACWO revealed that the procedure increases patellar height in all knees but did not induce significant differences in patellar height characteristics between knees with patella norma versus alta. A linear regression model revealed that a 1° decrease in mPTS could theoretically increase CDI by 0.02., Clinical Relevance: If preoperative planning indicates that supratuberosity ACWO would increase patellar height from norma (CDI <1.2) to alta (CDI ≥1.2), the surgeon could consider a trans- or infra-tuberosity ACWO, which is less likely to increase patellar height., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To provide comprehensive information about the anterolateral ligament (ALL) prevalence, morphometry, isometry, insertions, histology, and its relationship with the lateral meniscus (LM)., Methods: The study was performed, according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Eligible cadaveric studies investigating the frequency of the ALL presence, and anatomical features were identified through an online search of the PubMed, Scopus, and Cochrane Central databases from inception to June 2022. Statistical analysis was conducted with the open-source R programming language using the "meta" package. The Higgins I2 statistic was used for quantifying heterogeneity., Results: Thirty-three studies (1,478 cadaveric knees) were included. The ALL had a 79% prevalence. It was attached to the LM periphery in 97% of studies. Most studies reported a femoral insertion of the ALL, just proximal and posterior to the lateral epicondyle. Tibial attachment is constant at the midpoint between Gerdy's tubercle and fibular head. The mean ALL thickness at the joint line was 1.6 [1.2; 2.0] mm. The ALL length was found to significantly change across the knee flexion (P < .01). It was increased from 0° to 60° and decreased after 60° flexion. Seven histological studies demonstrated a typical ligamentous microstructure., Conclusion: The ALL is a thin ligament, distinct to the knee capsule, which may be found in 79% of the knees having an almost constant attachment to the LM. The ALL is not isometric. It becomes tense during internal rotation and between 30° and 60° knee flexion. Pooled results should be interpreted with caution due to the high heterogeneity among the included studies., Clinical Relevance: This study sheds light on controversial issues and provides comprehensive and accurate information about the essential anatomical knowledge on ALL, which may contribute to optimizing ALL reconstruction surgical techniques and biomechanical settings., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare the changes in patellofemoral (PF) joint alignment, focusing on multiple planes, between two different types of biplanar medial opening-wedge high tibial osteotomy (OWHTO)., Methods: Patients who underwent biplanar OWHTO between July 2017 and May 2021 were retrospectively evaluated. They were allocated to either the supra-tubercular (ST)- or retro-tubercular (RT)-OWHTO group. The following radiologic parameters were compared between the two groups: 1) weight-bearing line ratio (WBLR), 2) patellar height, 3) posterior tibial slope (PTS), 4) tibial tubercle-trochlear groove (TT-TG) distance, 5) TT-TG angle, and 6) femoral shaft-patellar tendon (FS-PT) angle. Clinical outcomes and the minimal clinically important difference (MCID) were also evaluated., Results: In total, 104 knees that underwent ST-OWHTO and 105 knees that underwent RT-OWHTO were evaluated. The patellar height significantly decreased only after ST-OWHTO (P < .001). The TT-TG distance and FS-PT angle significantly increased, more after ST-OWHTO than RT-OWHTO (mean change value: 5.72 mm vs 1.91 mm; P < .001 for TT-TG distance; and 4.72° vs 1.80°; P < .001 for FS-PT angle). The TT-TG angle increased significantly after ST-OWHTO (mean change value: 7.62°; P < .001) but decreased after RT-OWHTO mean change value: -4.30°; P < .001). The PTS more increased after RT-OWHTO than after ST-OWHTO (mean change value: 0.91° vs 1.69°; P = .003). Clinical outcomes in both groups improved postoperatively, and no significant differences were observed between the groups., Conclusions: RT-OWHTO resulted in lesser changes in multiplane PF joint alignment than ST-OWHTO. However, no difference was observed in clinical outcomes between both groups, and PTS increased after RT-OWHTO. Therefore, these aspects of RT-OWHTO should also be considered., Level of Evidence: Level III, retrospective cohort study., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To analyze the effect of the arthroscopic meniscal procedure in adult discoid lateral meniscus (DLM) according to the age and meniscal-preserving by making comparisons with the nondiscoid lateral meniscus (N-DLM)., Methods: From March 2014 to October 2020, a comparative analysis was performed in adults with DLM who underwent arthroscopic meniscal procedures (operative DLM: 134 knees), nonoperative treatment (nonoperative DLM: 56 knees), and adult N-DLM who underwent arthroscopic meniscal procedures (operative N-DLM: 64 knees). These patients were between 20 and 65 years old and completed a minimum follow-up of 2 years. Patients with DLM who underwent arthroscopic procedure were divided into subgroups according to age and extent of the meniscal-preserving. The following parameters were assessed and compared between the groups: (1) coronal limb alignment, (2) osteoarthritis grade, and (3) clinical outcomes and the minimal clinically important difference., Results: The coronal limb alignment was significantly changed to valgus in the order of operative DLM, N-DLM, and nonoperative DLM (Δ mechanical hip-knee-ankle angle: 3.23 ± 1.85 vs 1.35 ± 1.03° vs -0.57 ± 1.88°; P < .05). Operative DLM showed most prominent osteoarthritic change in the lateral compartment, followed by the N-DLM and nonoperative DLM groups (40.3% vs 17.2% vs 5.3%; P < .05). These changes in operative DLM were more prominent in older adults who underwent meniscal-sacrificing procedures and resulted in less-satisfactory clinical outcomes (all P < .05)., Conclusions: Arthroscopic surgery for adult DLM resulted in progression to valgus alignment and lateral compartment degeneration compared with nonoperative treatment and arthroscopic surgery of the adult N-DLM. Old ager and having a meniscal-sacrificing procedure showed more rapid radiographic changes and lower clinical outcomes., Level of Evidence: Level III, retrospective comparison study., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To report the clinical outcomes, radiologic evolution, and survivorship of a series of patients affected by the postmeniscectomy syndrome and treated with a polyurethane scaffold at a minimum 10-year follow-up. In addition, the radiologic evolution of these patients was also assessed., Methods: All the patients operated on with a polyurethane meniscal scaffold implantation to treat postmeniscectomy syndrome from 2008 to 2011 were prospectively followed. Clinical evaluations and radiologic studies were assessed at the preoperative period, at 5-year follow-up, and at minimum 10-year follow-up. Clinical outcomes were based on patient-reported outcomes (e.g., the Knee injury and Osteoarthritis Outcome Score, International Knee Documentation Committee, Lysholm, and Tegner). Radiographical evaluation of the joint-space narrowing was done in the Rosenberg view. Failure was defined as patients who required surgery to remove the scaffold or those patients who needed surgery for a total or partial knee replacement., Results: Twenty-one of 27 patients, with a mean age of 56 ± 9.8 years, were available for the final follow-up. The mean follow-up was 11.8 (range, 10-12.7) years. Six patients were lost to follow-up. All functional scores showed a significant improvement (P < .001) at the 5- and 10-year follow-up. The exception was the Tegner score, which remained stable. The joint-space width was maintained from the preoperative period (1.9 ± 1.2 mm) up to the 5-year follow-up (1.3 ± 1.5 mm, P = .3) and decreased by the last evaluation (0.6 ± 1.2 mm, P = .001) at the last follow-up. Two (9.5%) of 21 patients were converted to a total knee replacement during the study period. None of the other patients needed revision surgery during the study period., Conclusions: The polyurethane meniscal scaffold provides significant and stable pain relief over time and improved functional outcomes at a minimum of 10 years after surgery. However, degenerative changes progressed in the treated compartment, with a joint-space narrowing over the 10-year period., Level of Evidence: Level IV, retrospective case series., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To correlate changes in posterior tibial slope (PTS) with changes to static anterior tibial translation (SATT) with tibial deflexion osteotomy (TDO), in order to define a target postoperative tibial slope based on postoperative SATT., Methods: We reviewed a consecutive series of primary and revision anterior cruciate ligament reconstruction with TDO between 2011 and 2022. PTS and SATT were measured pre- and postoperatively directly from the radiographs by 2 independent reviewers. Regression analysis was performed to investigate the relationship of postoperative SATT with PTS, gender, graft type, and meniscal injury., Results: A total of 48 patients were included in this study. The mean (SD) decrease in PTS and SATT was 8.85° (3.03°; 12.5° to 3.59°, P < .01), and 7.93 mm (3.68; 5.37 to -2.55 mm, P < .01), respectively. Upon univariate analysis, the only factor influencing ΔSATT was ΔPTS. For each 1° of decreased slope, SATT was reduced by 0.46 mm. The mean (SD) PTS for a negative SATT was 2.81° (2.78°) compared to 5.09° (3.25°) for a SATT of 0 to 5mm (P < .01)., Conclusions: This study reports weightbearing SATT in association with PTS after TDO. The TDO successfully reduced the SATT, with the change in PTS the only significant predictor of postoperative SATT. Based on our results, our previously held target of 2° to 5° PTS overcorrected the SATT. Therefore, considering as a goal 0 to 5 mm of SATT, we suggest a new target of 4° to 6° PTS., Level of Evidence: Level IV, retrospective cohort study., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine clinical and radiographic outcomes of medial collateral ligament (MCL) pie-crusting during isolated medial meniscal root repair., Methods: A retrospective review was conducted between August 2013 and December 2019 in patients undergoing isolated medial meniscal root repair. Outcomes, including International Knee Documentation Committee (IKDC) score, Lysholm score, re-tears, MCL laxity, and conversion to total knee arthroplasty (TKA), were compared between pie crust (PC) and non-pie crust (NPC) cohorts. Other assessments included subjective instability or stiffness, infection, and intra-operative chondromalacia. Additionally, radiographic outcomes were compared to determine progression of medial compartment arthrosis., Results: Final analysis included 97 knees, 45 in the PC, and 52 in the NPC group. IKDC and Lysholm scores were similar between both groups preoperatively and 3 months postoperatively. However, at the 6,12, and 24-month follow up, the PC group had a significantly higher measured IKDC and Lysholm scores than the NPC group. PASS percentages for the IKDC score were significantly higher in the PC group at 6 months, 1 year, and 2 years (96.2%; P = .02) follow-up compared to the NPC group. MCID percentages for the IKDC score were also significantly higher at the 1- and 2-year (100%; P = .05) follow-up in the PC group compared to the NPC group. There was also a significantly higher rate of recurrent medial meniscal root tears in the NPC group (4 [8.9%]) compared to the PC group (0 [P = .03]). No MCL laxity was observed at 6 months follow-up., Conclusions: MCL pie-crusting during isolated medial meniscal root repair can be used as an alternative surgical technique, as it leads to improved clinical and patient outcomes compared to patients who do not undergo MCL pie-crusting in the short term. Additionally, those that underwent MCL pie-crusting had a lower incidence of recurrent tears, and no patients experienced MCL laxity at 6 months., Level of Evidence: Level III, retrospective cohort/comparative study., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Osteochondral injuries of the knee can be a frequent source of debilitating pain and dysfunction. Significant chondral (>1.5-2 cm 2 ) lesions of the femoral condyles can be especially difficult to manage with nonsurgical measures. Fresh osteochondral allograft (OCA) transplantation has been shown to be a reliable surgical procedure to manage a wide array of high-grade focal chondral lesions, with or without subchondral bone involvement. OCA transplantation affords the transfer of a size-matched allograft of mature hyaline cartilage with its associated subchondral bony scaffold. Indications include primary or secondary management of large, high-grade chondral or osteochondral defects secondary to trauma, developmental malformation, osteonecrosis, or other focal degenerative disease. Contraindications include end-stage osteoarthritis, uncorrected malalignment, ligament or meniscus deficiency, and inflammatory joint disease. Improvements in surgical technique, allograft storage, and tissue availability have created more reproducible clinical results and increased chondrocyte viability. Long-term (>10 year) graft survival rates have been shown to be between 70% and 91%, and the procedure has been shown to be cost-effective based on cost per quality-adjusted life year. Finally, OCA transplantation has been shown to provide excellent return to play rate for athletes with medium-to-large cartilage lesions. OCA transplantation is therefore an important option in the treatment algorithm of articular cartilage injuries., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare complication rates, reoperation rates, and subjective outcomes after arthroscopic and open irrigation and debridement for treatment of native knee septic arthritis., Methods: Following The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, a systematic review of the Embase, Cochrane, and PubMed databases was performed. Comparative studies reporting clinical outcomes after arthroscopic versus open treatment for septic arthritis of the native knee in human adults were included. Excluded were case series with <10 patients, inclusion of patients <18 years old, studies on non-native joints, abstract-only publications, and studies without stratification of the involved joint. Two reviewers in duplicate independently performed search and data extraction. The quality of the included studies was assessed with the Methodological Index for Non-Randomized Studies instrument. The mean score among the included studies was 18.2 (range 16-23)., Results: Eleven studies were included, comprising 2,343 knees treated arthroscopically, and 1,595 treated with arthrotomy. Studies reported no differences in erythrocyte sedimentation rate, C-reactive protein, peripheral white blood cells, or symptom chronicity between groups. Nine studies (81.8%) attempted to control for potentially confounding variables in their analyses, and 4 studies (36.4%) reported significant differences in patient characteristics. Reoperation rates ranged from 0% to 50% for arthroscopy and 6% to 71% for arthrotomy. Complication rates ranged from 0% to 39.4% arthroscopically and 0% to 49% for arthrotomy. Superior patient-reported outcomes were achieved after arthroscopy in 2 studies that analyzed subjective outcomes., Conclusions: Arthroscopic management of native knee septic arthritis is a safe and effective alternative to open treatment and is associated with comparable complication rates, reoperation rates, hospitalization lengths, readmission rates, and superior patient-reported outcomes compared with open irrigation and debridement., Level of Evidence: Level IV, systematic review of Level I, III, and IV studies., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To examine the biological changes in the joints of patients with knee osteoarthritis (OA) before and after around-knee osteotomy (AKO), focusing on synovial fluid (SF) and synovial pathological changes., Methods: Patients who underwent AKO for medial compartment knee OA between 2019 and 2021 were examined. SF and synovium were obtained at the time of AKO and plate removal after bone union (mean, 16.8 months [range: 11-38 months] postoperatively). SF volume and interleukin (IL)-6 concentrations in SF were assayed using enzyme-linked immunosorbent assay. Synovitis was assessed histologically using a semiquantitative scoring system. Macrophage infiltration was assessed by immunohistochemistry using a semiquantitative score for F4/80 expression. The M1/M2 ratio was calculated using percentage of cells positive for CD80 and CD163. The expression of proinflammatory cytokines was assessed by the percentage of IL-1β- and IL-6-positive cells. The number of vascular endothelial growth factor-positive luminal structures was counted to assess angiogenesis. The change in each parameter was compared before and after AKO using the Wilcoxon matched-pairs signed-rank test., Results: Twenty-four knees of 21 patients were included. SF volume and IL-6 concentration significantly decreased postoperatively (12.6 ± 2.1 mL vs 4.2 ± 0.6 mL; P < .0001 and 50.5 ± 8.6 pg/mL vs 20.7 ± 3.8 pg/mL; P = .0001, respectively). A significant reduction in synovitis score (P = .0001), macrophage infiltration (P < .0003), M1/M2 ratio (P < .0007), angiogenesis (P < .0001), and the percentage of IL-1β- and IL-6-positive cells in the intima (P < .008 and P < .002, respectively) was found after AKO., Conclusions: SF volume and IL-6 concentrations in the SF decreased and inflammatory synovium pathology improved after AKO. In addition to biomechanical changes, the biological environment of the joint can be improved after AKO., Level of Evidence: Level IV, retrospective therapeutic case series., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To create a cut-off point for hyperextension that best discriminates retear and to verify whether this cut-off point can predict retear regardless of other characteristics after primary anterior cruciate ligament (ACL) reconstruction with hamstrings autograft., Methods: A cohort of patients submitted to primary isolated ACL reconstruction with hamstrings autografts was retrospectively evaluated. Patients were stratified according to the degree of passive knee hyperextension measured in the normal contralateral knee. The following data were collected: patient age and sex, time from injury to surgery, knee hyperextension, KT-1000 and pivot-shift, associated meniscus injury, intra-articular graft size, follow-up time, graft failure, and postoperative Lysholm and subjective International Knee Documentation Committee scores., Results: Data from 457 patients were evaluated. Median age was 31 years. Thirty-two (7.0%) presented with retear. There was a significant difference in hyperextension between patients with and without retear (P < .001), with the cut-off point established by the receiver operating characteristic curve from 6.5°. Patients with greater hyperextension had a statistically greater frequency of women, longer injury time, greater intra-articular graft diameter, greater postoperative KT-1000, and greater frequency of retear, whereas the subjective International Knee Documentation Committee and Lysholm scores were statistically lower in patients with greater hyperextension. Only hyperextension showed a statistically significant association with re-rupture (P < .001). The odds of retear in patients with hyperextension greater than 6.5 was 14.65 times the odds of patients with hyperextension less than 6.5., Conclusions: Patients with more than 6.5° of hyperextension are 14.6 times more likely to have a graft rupture than patients with lower hyperextension when submitted to ACL reconstruction with hamstring tendons. Also, they present worse knee stability by the KT-1000 test and worse functional outcomes. Therefore, patients with this degree of hyperextension should not have isolated reconstruction with hamstrings as their first choice., Level of Evidence: Level III, retrospective comparative prognostic trial., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To confirm whether posterior displacement of the detached meniscocapsular structure in ramp lesions could be observed on magnetic resonance imaging (MRI) in the flexed knee position and to clarify whether this displacement on MRI is related to greater anterior knee laxity., Methods: This retrospective comparative trial study included 50 patients with anterior cruciate ligament injuries in whom attendant ramp lesions were observed on preoperative MRI. All patients underwent 3-T MRI at 120° of knee flexion preoperatively. The gap distance of the ramp lesion on sagittal slices was measured, and a distance greater than 1 mm was classified as gap positive. Additionally, joint effusion in the posteromedial recess was quantitatively evaluated by measuring the surface area of joint fluid. Prior to surgery, the side-to-side difference in anterior tibial translation (ATT) on stress radiographs at 20° of knee flexion was measured to evaluate anterior knee laxity. During anterior cruciate ligament reconstruction, the length of the ramp lesion was measured by a scale from the posteromedial portal., Results: Of the 50 knees, 29 had ramp lesion gaps greater than 1 mm on MRI at knee flexion. The gap-positive group had a significantly greater side-to-side difference in ATT (9.6 ± 3.6 mm vs 5.0 ± 2.7 mm, P < .001) and significantly larger ramp lesion length (15.7 ± 4.9 mm vs 11.7 ± 3.9 mm, P = .002) than the gap-negative group. The gap-positive group also had a significantly greater amount of joint effusion than the gap-negative group (P < .001)., Conclusions: Posterior displacement of the detached meniscocapsular structure in ramp lesions can be observed on MRI at knee flexion and is related to greater anterior knee laxity, lesion size, and joint effusion., Level of Evidence: Level III, retrospective comparative trial., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To report the mid-term outcomes of patients who underwent revision meniscal allograft transplantation (RMAT) and compare survivorship free from reoperation and failure with a matched cohort of patients who underwent primary meniscal allograft transplantation (PMAT)., Methods: A retrospective review of prospectively collected data identified patients who underwent RMAT and PMAT between 1999 and 2017. A cohort of PMAT patients matched at a ratio of 2:1 with respect to age, body mass index, sex, and concomitant procedures served as the control group. Patient-reported outcome measures (PROMs) at baseline and at a minimum of 5 years postoperatively were collected. PROMs and the achievement of clinically significant outcomes were analyzed within groups. Graft survivorship free from meniscal reoperation and failure (arthroplasty or subsequent RMAT) was compared between cohorts using log-rank testing., Results: During the study period, 22 RMATs were performed in 22 patients. Of these RMAT patients, 16 met the inclusion criteria (73% follow-up rate). The mean age of RMAT patients was 29.7 ± 9.3 years, and the mean follow-up period was 9.9 ± 4.2 years (range, 5.4-16.8 years). There were no differences between the RMAT cohort and the 32 matched PMAT patients with respect to age (P = .292), body mass index (P = .623), sex (P = .537), concomitant procedures (P ≥ .286), or baseline PROMs (P ≥ .066). The patient acceptable symptomatic state was achieved by the RMAT cohort for the subjective International Knee Documentation Committee score (70%), Lysholm score (38%), and Knee Injury and Osteoarthritis Outcome Score subscales (Pain [73%], Symptoms [64%], Sport [45%], Activities of Daily Living [55%], and Quality of Life [36%]). In the RMAT cohort, 5 patients (31%) underwent subsequent reoperation at a mean of 4.7 ± 2.1 years (range, 1.7-6.7 years) and 5 patients met the criteria for failure at a mean of 4.9 ± 2.9 years (range, 1.2-8.4 years). There were no significant differences in survivorship free from reoperation (P = .735) or failure (P = .170) between the RMAT and PMAT cohorts., Conclusions: At mid-term follow-up, most patients who underwent RMAT achieved the patient acceptable symptomatic state for the subjective International Knee Documentation Committee score and the Knee Injury and Osteoarthritis Outcome Score subscales of Pain, Symptoms, and Activities of Daily Living. Additionally, there were no differences in survival free from meniscal reoperation or failure between the PMAT and RMAT cohorts., Level of Evidence: Level III, retrospective comparative cohort., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine whether the addition of lateral extra-articular tenodesis (LET) to anterior cruciate ligament reconstruction (ACLR) would improve return-to-sport (RTS) rates in young, active patients who play high-risk sports., Methods: This multicenter randomized controlled trial compared standard hamstring tendon ACLR with combined ACLR and LET using a strip of the iliotibial band (modified Lemaire technique). Patients aged 25 years or younger with an anterior cruciate ligament-deficient knee were included. Patients also had to meet 2 of the following criteria: (1) pivot-shift grade 2 or greater, (2) participation in a high-risk or pivoting sport, and (3) generalized ligamentous laxity. Time to return and level of RTS were determined via administration of a questionnaire at 24 months postoperatively., Results: We randomized 618 patients in this study, 553 of whom played high-risk sports preoperatively. The proportion of patients who did not RTS was similar between the ACLR (11%) and ACLR-LET (14%) groups; however, the graft rupture rate was significantly different (11.2% in ACLR group vs 4.1% in ACLR-LET group, P = .004). The most cited reason for no RTS was lack of confidence and/or fear of reinjury. A stable knee was associated with nearly 2 times greater odds of returning to a high-level high-risk sport postoperatively (odds ratio, 1.92; 95% confidence interval, 1.11-3.35; P = .02). There were no significant differences in patient-reported functional outcomes or hop test results between groups (P > .05). Patients who returned to high-risk sports had better hamstring symmetry than those who did not RTS (P = .001)., Conclusions: At 24 months postoperatively, patients who underwent ACLR plus LET had a similar RTS rate to those who underwent ACLR alone. Although the subgroup analysis did not show a statistically significant increase in RTS with the addition of LET, on returning, the addition of LET kept subjects playing longer by reducing graft failure rates., Level of Evidence: Level I, randomized controlled trial., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To obtain a comprehensive overview of comparative biomechanical cadaveric studies investigating the effect of both the iliotibial band (ITB) and anterolateral ligament (ALL) on anterolateral rotatory instability (ALRI) in anterior cruciate ligament (ACL)-injured knees, and the effect of lateral extra-articular tenodesis (LET) versus ALL reconstruction (ALLR) in ACL-reconstructed knees., Methods: An electronic search was performed in the Embase and MEDLINE databases for the period between January 1, 2010, and October 1, 2022. All sectioning studies comparing the role of both the ITB and ALL on ALRI and all studies comparing the effect of both LET and ALLR were included. Articles were assessed for methodological quality according to the Quality Appraisal for Cadaveric Studies scale., Results: Data of 15 studies were included, representing the mean values of biomechanical data collected from 203 cadaveric specimens, with sample sizes ranging from 10 to 20 specimens. All 6 sectioning studies reported that the ITB acts as a secondary stabilizer to the ACL and helps resist internal knee rotation, whereas in only 2 of 6 sectioning studies the ALL contributed significantly to tibial internal rotation (IR). Most reconstruction studies reported that both a modified Lemaire tenodesis and an ALLR could significantly reduce the residual ALRI in isolated ACL-reconstructed knees and were able to restore IR stability/IR stability during the pivot shift., Conclusions: The ITB acts as the main secondary stabilizer to the ACL in resisting IR/IR during pivot shift and an anterolateral corner (ALC) reconstruction with either a modified Lemaire tenodesis and ALLR can improve residual knee rotatory laxity in ACL reconstructed knees., Clinical Relevance: This systematic review provides insight in the biomechanical function of the ITB and ALL and emphasizes the importance of adding an ALC reconstruction to ACL reconstruction., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate outcomes of arthroscopic single-bundle (SB) versus anatomic double-bundle (ADB) anterior cruciate ligament reconstruction (ACLR) in adults through a synthesis of randomized controlled trials (RCTs). We hypothesized that SB and ADB methods would lead to similar outcomes after reconstruction of ACL rupture., Methods: The Preferred Reporting Items for Systematic Reviews and Meta-analyses checklist guided our reporting. To identify RCTs that compared SB and ADB reconstructions, a thorough literature search was conducted of PubMed, Embase, Cochrane library, and Web of Science. The methodologic quality of each included study was independently assessed by 2 authors using the Cochrane Collaboration's risk of bias tool. The Anatomic ACL Reconstruction Scoring Checklist (AARSC) was used to screen the eligibility of each study's operative approaches. Twelve clinical outcomes were investigated through pooled analyses conducted using Review Manager 5.3., Results: This meta-analysis synthesized 13 RCTs comparing postoperative outcomes between ADB and SB reconstructions of ACLs. After a minimum follow-up of 12 months, ADB and SB technique resulted in similar subjective clinical outcomes, including the International Knee Documentation Committee subjective score, Lysholm score, Tegner activity score, and Knee injury and Osteoarthritis Outcome Score sports subscale. Similarly, no statistically significant outcomes were found for objective outcomes such as International Knee Documentation Committee objective grade, pivot-shift test, Lachman test, side-to-side difference, extension deficit, flexion deficit, and osteoarthritis change. However, patients who underwent SB reconstruction had significantly greater complication rates than those that underwent ADB reconstruction., Conclusions: When an ACLR approach meets a minimal total AARSC score of 8, ADB and SB techniques may result in similar subjective and objective outcomes, but the ADB technique may lead to lower complication rates following surgery. We recommend that surgeons favor ADB ACLR, as guided by the AARSC., Level of Evidence: Level I, systematic review and meta-analysis of Level I randomized controlled trials., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Purpose: To identify risk factors for patients who sustain nontraumatic anterior cruciate ligament reconstruction (ACLR) failure., Methods: A retrospective analysis was performed on patients undergoing primary or revision ACLR in our institution between 2010 and 2018. Patients sustaining insidious-onset knee instability without history of trauma were identified as nontraumatic ACLR failure and assigned to the study group. The control group of subjects who showed no evidence of ACLR failure with minimum 48-month follow-up were matched in a 1:1 ratio based on age, sex, and body mass index. Anatomic parameters including tibial slope (lateral [LTS], medial [MTS]); tibial plateau subluxation (lateral [LTPsublx], medial [MTPsublx]); notch width index (NWI); and lateral femoral condyle ratio were measured with magnetic resonance imaging or radiography. Graft tunnel position was assessed using 3-dimensional computed tomography and reported in 4 dimensions: deep-shallow ratio (DS ratio) and high-low ratio for femoral tunnel, anterior-posterior ratio and medial-lateral ratio for tibial tunnel. Interobserver and intraobserver reliability were evaluated by the intraclass correlation coefficient (ICC). Patients' demographic data, surgical factors, anatomic parameters, and tunnel placements were compared between the groups. Multivariate logistic regression and receiver operating characteristic curve analysis was used to discriminate and assess the identified risk factors., Results: A total of 52 patients who sustained nontraumatic ACLR failure were included and matched with 52 control subjects. Compared to patients with intact ACLR, those who sustained nontraumatic ACLR failure showed significantly increased LTS, LTPsublx, MTS, and deceased NWI (all P < .001). Moreover, the average tunnel position in the study group was significantly more anterior (P < .001) and superior (P = .014) at the femoral side and more lateral (P = .002) at the tibial side. Multivariate regression analysis identified LTS (odds ratio [OR] = 1.313; P = .028), DS ratio (OR = 1.091; P = .002), and NWI (OR = 0.813; P = .040) as independent predictors of nontraumatic ACLR failure. LTS appeared to be the best independent predictive factor (area under the curve [AUC] = 0.804; 95% confidence interval [CI], 0.721-0.887), followed by DS ratio (AUC = 0.803; 95% CI, 0.717-0.890), and NWI (AUC = 0.756; 95% CI, 0.664-0.847). The optimal cutoff values were 6.7° for increased LTS (sensitivity = 0.615, specificity = 0.923); 37.4% for increased DS ratio (sensitivity = 0.673, specificity = 0.885); and 26.4% for decreased NWI (sensitivity = 0.827, specificity = 0.596). Intraobserver and interobserver reliability was good to excellent, with ICCs ranging from 0.754 to 0.938 for all radiographical measurements., Conclusions: Increased LTS, decreased NWI, and femoral tunnel malposition are predictive risk factors for nontraumatic ACLR failure., Level of Evidence: Level III, retrospective comparative study., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To assess the prevalence of and factors associated with medial collateral ligament (MCL) complex injuries on magnetic resonance imaging (MRI) in patients with anterior cruciate ligament (ACL) tears., Methods: Data were extracted from the Natural Corollaries and Recovery After ACL Injury (NACOX) multicenter longitudinal cohort study. Between May 2016 and October 2018, patients who presented to 1 of 7 health care clinics across Sweden with an ACL tear sustained no more than 6 weeks earlier and who were aged between 15 and 40 years at the time of injury were invited to participate. All the patients included in this study underwent MRI. The mean time from injury to MRI was 19.6 ± 15.2 days. An orthopaedic surgeon specializing in knee surgery and a musculoskeletal radiologist reviewed all MRI scans. Injuries to the superficial MCL (sMCL), deep MCL (dMCL), and posterior oblique ligament were identified. Stepwise forward multiple binary logistic regression analyses were used to evaluate patient characteristics (age, sex, body mass index, preinjury Tegner activity level, and activity at injury) and injuries on MRI (lateral meniscus [LM] injury, medial meniscus [MM] injury, pivot shift-type bone bruising, medial femoral condyle [MFC] bone bruising, and lateral femoral condyle [LFC] impaction) associated with the presence of MCL complex tears., Results: In total, 254 patients (48.4% male patients) with a mean age of 25.4 ± 7.1 years were included. The overall prevalence of MCL (sMCL and dMCL) injuries and isolated dMCL injuries was 16.5% (42 of 254) and 24.8% (63 of 254), respectively. No isolated sMCL injuries were found. Posterior oblique ligament injuries were found in 12 patients (4.7%) with MCL (sMCL and dMCL) injuries. An LM injury (odds ratio [OR], 3.94; 95% confidence interval [CI], 1.73-8.94; P = .001) and LFC impaction (OR, 2.37; 95% CI, 1.11-5.07; P = .02) increased the odds of having an MCL injury, whereas an MM injury (OR, 0.26; 95% CI, 0.12-0.59; P = .001) reduced the odds. Isolated dMCL injuries were significantly associated with MFC bone bruising (OR, 4.21; 95% CI, 1.92-9.25; P < .001) and LFC impaction (OR, 3.86; 95% CI, 1.99-7.49; P < .001)., Conclusions: The overall combined prevalence of MCL (sMCL and dMCL) injuries and isolated dMCL injuries in patients with ACL tears was high (16.5% + 24.8% = 41.3%). The presence of an LM injury and LFC impaction increased the odds of having an MCL injury, whereas the presence of an MM injury reduced the odds. MFC bone bruising and LFC impaction were associated with the presence of isolated dMCL injuries., Level of Evidence: Level III, retrospective cohort study., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the clinical and radiologic outcomes of open-wedge high tibial osteotomy (OWHTO) with respect to the patellofemoral joint and to assess the effects of patellofemoral osteoarthritis (OA) progression after OWHTO on clinical outcomes at minimum 7 years' follow-up., Methods: We retrospectively reviewed 95 knees that underwent OWHTO and at least 7 years of follow-up. Clinical parameters including anterior knee pain, Japanese Orthopedic Association score, Oxford Knee Score, Knee Injury and Osteoarthritis Outcome Score, Hospital for Special Surgery patella score, and Knee Injury and Osteoarthritis Outcome Score-patellofemoral subscale were evaluated. Radiologic outcomes were evaluated preoperatively and at final follow-up. Patellofemoral OA progressions were evaluated using Kellgren-Lawrence grade, and we divided the patients into 2 groups (progression group and non-progression group) to evaluate the effect of patellofemoral OA progression after OWHTO on long-term clinical outcomes., Results: The mean follow-up period was 10.8 ± 2.6 years (range: 7.6-17.3 years). The mean Japanese Orthopedic Association score significantly improved (from 64.4 ± 11.6 to 90.9 ± 9.3, P < .001), and the mean Oxford Knee Score at final follow-up was 40.4 ± 8.3. Due to medial OA progression, 5 cases were converted to total knee arthroplasty, and the survival rate was 94.7% at 10.8 years of follow-up. Radiologically, patellofemoral OA progression was observed at final follow-up in 48 knees (50.5%). However, there were no significant differences in all clinical outcomes at final follow-up between the progression and non-progression groups., Conclusions: Patellofemoral OA progression may progress over long-term follow-up after OWHTO. Related symptoms are minimal and this does not affect the clinical outcomes or survivorships at minimum 7 years follow-up., Level of Evidence: Level IV, therapeutic case series., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

The 3 primary factors involved with preservation of the knee joint include joint alignment, meniscal status, and ligament stability (in particular that of the anterior cruciate ligament [ACL]). These factors are interdependent and result in knee joint homeostasis when all factors are stable. When a deficiency exists in one of the factors, it will affect the others. For example, the ACL and posterior horn of the medial meniscus both act as restraints to anterior tibial translation. Thus, medial meniscal deficiency increases the risk for failure of ACL reconstruction, and chronic ACL insufficiency increases the risk for medial meniscus tears. Furthermore, all 3 of the factors of joint preservation have an impact on the articular cartilage status of the knee joint. Studies have shown that cartilage-preservation procedures do not result in optimal outcomes if there is joint malalignment, meniscal deficiency, or ligament deficiency. When evaluating patients with knee cartilage pathology, surgeons should be aware of the various factors involved in knee joint preservation and, if surgery is indicated, all factors should be addressed in order to support a successful result., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare the clinical, radiographic, and second-look arthroscopic outcomes between double-bundle (DB) anterior cruciate ligament (ACL) reconstruction (DB group) and combined single-bundle (SB) ACL and anterolateral ligament (ALL) reconstruction (SB + ALL group) by a prospective randomized controlled trial., Methods: From May 2019 to June 2020, 84 patients were enrolled in this study. Among them, 10 were lost to follow-up. Thirty-six and 38 patients were successfully allocated to the DB (mean follow up 27.3 ± 4.2 months) and SB + ALL groups (27.2 ± 4.5 months), respectively. The preoperative and postoperative Lachman test, pivot shift test, anterior translation on stress radiographs, KT-2000 arthrometer, Lysholm score, International Knee Documentation Committee score, and Tegner activity score were evaluated and compared. Graft continuity was evaluated using postoperative magnetic resonance imaging (MRI) (32 and 36 patients underwent MRI in the DB and SB + ALL groups at 7.4 ± 3.2 and 7.5 ± 2.9 months after surgery, respectively), and second-look examinations (second-look examination and tibial screw removal were performed concomitantly when patients (1) had tibial screw-related irritation or (2) needed the screws removed, 28 and 23 patients underwent examinations in the DB and SB + ALL groups at 24.0 ± 6.8 and 24.9 ± 8.1 months after surgery, respectively). All measurements were compared between the groups., Results: Postoperative clinical outcomes significantly improved in both groups. (All variables showed P < .001) No statistically different outcomes were found between the 2 groups. Additionally, postoperative graft continuity on MRI and second-look examinations were not different between the 2 groups., Conclusions: The DB and SB + ALL groups showed similar postoperative clinical, radiographic, and second-look arthroscopic outcomes. Both groups showed excellent postoperative stability and clinical outcomes compared with the preoperative measurements., Level of Evidence: Level II, randomized controlled trial., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine whether bipolar lesions (BL) are associated with inferior clinical outcome following articular cartilage regeneration (CR) compared to unipolar lesions (UL)., Methods: A registry-based study, including patients undergoing isolated CR for focal knee cartilage lesions was performed. Lesions were considered UL or BL depending on the opposing cartilage. Propensity score matching was applied to eliminate potential confounders. Two groups comprising 119 patients with similar baseline characteristics were matched. The Knee Injury and Osteoarthritis Outcome Score (KOOS) at baseline, 6, 12, 24, and 36 months following CR served as primary outcome measure. KOOS improvement, reaching the minimal clinically important difference (MCID), KOOS subcomponents, and failure rates were calculated., Results: Autologous chondrocyte implantation (ACI) was the most frequently performed procedure in both groups with 63.0% (BL) and 46.6% (UL). There was a significant difference regarding KOOS at 24 months between UL (76.39 ± 14.96) and BL (69.83 ± 18.83; P = .028), which did not exceed the threshold of MCID. No significant difference was detected at any other follow-up. KOOS improvement from baseline was lower in the BL group at all follow-ups and peaked at 36 months in both groups (UL [26.00 ± 16.12] vs. BL [16.63 ± 17.29]; P = .024). The failure rate in the BL group was higher at 8.2% (9/110) compared to the UL group at 3.9% (4/98) (P = .256)., Conclusions: BL were associated with worse clinical outcome 2 years following CR compared to UL. However, both groups showed an ongoing clinical improvement up to 3 years postoperatively and a low failure rate. While inferior clinical improvement and a lower clinical response rate may be expected in BL patients, the observed differences do not justify excluding these patients from CR., Level of Evidence: Level III, retrospective comparative prognostic trial., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Purpose: To compare patient-reported outcomes and complications in patients with medial collateral ligament (MCL) injuries undergoing repair versus reconstruction with a minimum 2-year follow-up., Methods: A literature search was conducted using the PubMed, Scopus, and Embase-computerized databases from database inception to November 2022, according to the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies evaluating clinical outcomes and complications at a minimum of 2 years following MCL repair versus reconstruction were included. Study quality was assessed using the MINORS criteria., Results: A total of 18 studies published from 1997 to 2022, consisting of 503 patients were identified. Twelve studies (n = 308 patients; mean age: 32.6 years) reported outcomes following MCL reconstruction, and 8 studies (n = 195 patients; mean age: 28.5 years) reported results following MCL repair. Postoperative International Knee Documentation Committee, Lysholm, and Tegner scores ranged from 67.6 to 91, 75.8 to 94.8, and 4.4 to 8, respectively, in the MCL reconstruction group, compared to 73 to 91, 75.1 to 98.5, and 5.2 to 10, respectively, in the MCL repair group. Knee stiffness was the most commonly reported complication following MCL repair (range: 0% - 50%) and reconstruction (range: 0% - 26.7%). Failures occurred in 0% to 14.6% of patients following reconstruction versus 0% to 35.1% of patients undergoing MCL repair. Manipulation under anesthesia (MUA) for postoperative arthrofibrosis (range: 0% - 12.2%) and surgical debridement for arthrofibrosis (range: 0% - 20%) were the most commonly reported reoperations in the MCL reconstruction and repair groups, respectively., Conclusions: MCL reconstruction versus repair both demonstrate improved International Knee Documentation Committee, Lysholm, and Tegner scores. MCL repair demonstrates higher rates of postoperative knee stiffness and failure at a minimum 2-year follow-up., Level of Evidence: Level IV, systematic review of Level III and IV studies., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare the articular cartilage regeneration based on second-look arthroscopy in patients who underwent medial open-wedge high tibial osteotomy (MOWHTO) combined with particulated costal hyaline cartilage allograft (PCHCA) implantation with those who underwent MOWHTO and subchondral drilling (SD). Moreover, we compared the clinical and radiographic outcomes between the groups., Methods: From January 2014 to November 2020, patients with full-thickness cartilage defect on the medial femoral condyle who underwent MOWHTO combined with PCHCA (group A) or SD (group B) were reviewed. Fifty-one knees were matched after propensity score matching. The status of regenerated cartilage was classified according to the International Cartilage Repair Society-Cartilage Repair Assessment (ICRS-CRA) grading system and Koshino staging system, based on second-look arthroscopic findings. Clinically, the Knee Injury and Osteoarthritis Outcome Score, the Western Ontario and McMaster Universities Osteoarthritis Index, and range of motion were compared. Radiographically, we compared the differences in the minimum joint space width (JSW) and change in JSW., Results: The average age was 55.5 years (range, 42-64 years), and the average follow-up period was 27.1 months (range, 24-48 months). Group A showed a significantly better cartilage status than group B based on the ICRS-CRA grading system and Koshino staging system (P < .001 and <.001, respectively). There were no significant differences in clinical and radiographic outcomes between groups. In group A, the minimum JSW at the last follow-up was significantly increased than that before surgery (P = .013), and a significantly greater increase in JSW was observed in group A (P = .025)., Conclusions: When performed with MOWHTO, the combination of SD and PCHCA was associated with superior articular cartilage regeneration on the ICRS-CRA grading and Koshino staging on second-look arthroscopy performed at a minimum of 2 years follow-up than SD alone. However, there was no difference in clinical outcomes., Level of Evidence: Level III, retrospective comparative study., (Copyright © 2023 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)