Search

Background: Recently there have been several evolving trends in the practice of shoulder surgery. Arthroscopic subacromial decompression has been performed with greater frequency by orthopaedic surgeons, and there has been considerable recent interest in arthroscopic rotator cuff repair. The purpose of this study was to identify trends in practice patterns for subacromial decompression and rotator cuff repair over time and in relation to the location of practice, fellowship training, and declared subspecialty of the surgeon.Methods: We reviewed the American Board of Orthopaedic Surgery Part II database to identify patterns in the utilization of open and arthroscopic subacromial decompression and rotator cuff repair among candidates for board certification. All procedures involving only arthroscopic or open subacromial decompression and/or rotator cuff repair from 2004 to 2009 were identified. The rates of arthroscopic and open subacromial decompression and/or rotator cuff repair were compared in terms of year, geographic region, fellowship training, and declared subspecialty of the surgeon.Results: Between 2004 and 2009, 12,136 surgical procedures involving only arthroscopic or open subacromial decompression and/or rotator cuff repair were performed. There were significant differences in treatment with respect to year, geographic region of practice, declared subspecialty, and fellowship training (p < 0.001). There was a significant increase over time in the utilization of arthroscopy among all candidates (p < 0.001). Surgeons with sports medicine fellowship training or a sports-medicine-declared subspecialty performed significantly more subacromial decompressions and rotator cuff repairs arthroscopically than all other candidates (p < 0.001). During this time period, there was a significant decrease in the rate of arthroscopic subacromial decompression, both as an isolated procedure and combined with arthroscopic rotator cuff repair (p < 0.001).Conclusions: From 2004 to 2009, there was a significant shift throughout the United States toward arthroscopic rotator cuff repair and subacromial decompression among young orthopaedic surgeons, with sports medicine fellowship-trained surgeons performing more of their procedures arthroscopically than surgeons with other training. However, there was an increasing frequency of arthroscopic rotator cuff repair performed without subacromial decompression, and, overall, there was a decrease in the frequency of isolated arthroscopic subacromial decompression over time. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to examine clinical and patient-reported outcomes as well as return to sport in athletes younger than 25 following ACL reconstruction with either bone-patellar tendon-bone (BTB) or hamstring (HS) autografts using a matched-pairs case-control experimental design.Methods: Twenty-three matched pairs were obtained based on gender (57% women), age (18 ± 3 years BTB vs. 18 ± 3 HS), and length of follow-up (5 ± 2 years BTB vs. 4 ± 2 HS). Patients reported participating in very strenuous (soccer, basketball, etc.) or strenuous (skiing, tennis, etc.) sporting activity 4-7 times/week prior to their knee injury. Patient-reported outcomes included return to play data, the IKDC, SAS, ADLS, and SF-36 forms. Clinical outcomes included knee range of motion, laxity, and hop/jump testing.Results: The majority of patients in both groups were able to participate in very strenuous or strenuous sporting activity 4-7 times per week following surgery [17 (74%) BTB vs. 16 (70%) HS]. However, only 13 (57%) of the BTB subjects and 10 (44%) of the HS patients were able to return to pre-injury activity levels (P = n.s.). HS patients showed higher ADLS (P < 0.01) and SAS (P < 0.01) scores, better restoration of extension (P < 0.05), and less radiographic evidence of osteoarthritis (P < 0.05).Conclusions: Hamstring and bone-patellar tendon-bone autografts allow approximately 70% of young athletes to return to some degree of strenuous or very strenuous sporting activity, while only approximately half of patients were able to return to their pre-injury sporting activity level. Hamstring grafts lead to better preservation of extension, higher patient-reported outcome scores, and less radiographic evidence of osteoarthritis.Level Of Evidence: Therapeutic (case-control study) Level III. [ABSTRACT FROM AUTHOR]

Background: Tears of the posterior root of the medial meniscus are becoming increasingly recognized. They can cause rapidly progressive arthritis, yet their biomechanical effects are not understood. The goal of this study was to determine the effects of posterior root tears of the medial meniscus and their repairs on tibiofemoral joint contact pressure and kinematics.Methods: Nine fresh-frozen cadaver knees were used. An axial load of 1000 N was applied with a custom testing jig at each of four knee-flexion angles: 0 degrees , 30 degrees , 60 degrees , and 90 degrees . The knees were otherwise unconstrained. Four conditions were tested: (1) intact, (2) a posterior root tear of the medial meniscus, (3) a repaired posterior root tear, and (4) a total medial meniscectomy. Fuji pressure-sensitive film was used to record the contact pressure and area for each testing condition. Kinematic data were obtained by using a robotic arm to record the position of the knees for each loading condition. Three-dimensional knee kinematics were analyzed with custom programs with use of previously described transformations. The measured variables were axial rotation, varus angulation, lateral translation, and anterior translation.Results: In the medial compartment, a posterior root tear of the medial meniscus caused a 25% increase in peak contact pressure compared with that found in the intact condition (p < 0.001). Repair restored the peak contact pressure to normal. No difference was detected between the peak contact pressure after the total medial meniscectomy and that associated with the root tear. The peak contact pressure in the lateral compartment after the total medial meniscectomy was up to 13% greater than that for all other conditions (p = 0.026). Significant increases in external rotation and lateral tibial translation, compared with the values in the intact knee, were observed in association with the posterior root tear (2.98 degrees and 0.84 mm, respectively) and the meniscectomy (4.45 degrees and 0.80 mm, respectively), and these increases were corrected by the repair.Conclusions: This study demonstrated significant changes in contact pressure and knee joint kinematics due to a posterior root tear of the medial meniscus. Root repair was successful in restoring joint biomechanics to within normal conditions. [ABSTRACT FROM AUTHOR]

Background: Tears of the posterior root of the medial meniscus are becoming increasingly recognized. They can cause rapidly progressive arthritis, yet their biomechanical effects are not understood. The goal of this study was to determine the effects of posterior root tears of the medial meniscus and their repairs on tibiofemoral joint contact pressure and kinematics.Methods: Nine fresh-frozen cadaver knees were used. An axial load of 1000 N was applied with a custom testing jig at each of four knee-flexion angles: 0 degrees, 30 degrees, 60 degrees, and 90 degrees. The knees were otherwise unconstrained. Four conditions were tested: (1) intact, (2) a posterior root tear of the medial meniscus, (3) a repaired posterior root tear, and (4) a total medial meniscectomy. Fuji pressure-sensitive film was used to record the contact pressure and area for each testing condition. Kinematic data were obtained by using a robotic arm to record the position of the knees for each loading condition. Three-dimensional knee kinematics were analyzed with custom programs with use of previously described transformations. The measured variables were axial rotation, varus angulation, lateral translation, and anterior translation.Results: In the medial compartment, a posterior root tear of the medial meniscus caused a 25% increase in peak contact pressure compared with that found in the intact condition (p < 0.001). Repair restored the peak contact pressure to normal. No difference was detected between the peak contact pressure after the total medial meniscectomy and that associated with the root tear. The peak contact pressure in the lateral compartment after the total medial meniscectomy was up to 13% greater than that for all other conditions (p = 0.026). Significant increases in external rotation and lateral tibial translation, compared with the values in the intact knee, were observed in association with the posterior root tear (2.98 degrees and 0.84 mm, respectively) and the meniscectomy (4.45 degrees and 0.80 mm, respectively), and these increases were corrected by the repair.Conclusions: This study demonstrated significant changes in contact pressure and knee joint kinematics due to a posterior root tear of the medial meniscus. Root repair was successful in restoring joint biomechanics to within normal conditions. [ABSTRACT FROM AUTHOR]

A more complete biomechanical understanding of a combined posterior cruciate ligament and posterolateral corner knee reconstruction may help surgeons develop uniformly accepted clinical surgical techniques that restore normal anatomy and protect the knee from premature arthritic changes. We identified the in situ force patterns of the individual components of a combined double-bundle posterior cruciate ligament and posterolateral corner knee reconstruction. We tested 10 human cadaveric knees using a robotic testing system by sequentially cutting and reconstructing the posterior cruciate ligament and posterolateral corner. The knees were subjected to a 134-N posterior tibial load and 5-Nm external tibial torque. The posterior cruciate ligament was reconstructed with a double-bundle technique. The posterolateral corner reconstruction included reattaching the popliteus tendon to its femoral origin and reconstructing the popliteofibular ligament. The in situ forces in the anterolateral bundle were greater in the posterolateral corner-deficient state than in the posterolateral corner-reconstructed state at 30 degrees under the posterior tibial load and at 90 degrees under the external tibial torque. We observed no differences in the in situ forces between the anterolateral and posteromedial bundles under any loading condition. The popliteus tendon and popliteofibular ligament had similar in situ forces at all flexion angles. The data suggest the two bundles protect each other by functioning in a load-sharing, codominant fashion, with no component dominating at any flexion angle. We believe the findings support reconstructing both posterior cruciate ligament bundles and both posterolateral corner components. [ABSTRACT FROM AUTHOR]

Participants of contact sports are at risk for outbreaks of skin and soft tissue infection. Causes of reported outbreaks include Staphylococcus aureus, herpes simplex virus, Streptococcus pyogenes, and several fungi. Although once thought of solely as a nosocomial pathogen, methicillin-resistant Staphylococcus aureus has been identified as an emerging problem in the community, particularly in the athletic population. Despite a recent increase in reported outbreaks of community-acquired methicillin-resistant Staphylococcus aureus soft tissue infection in athletic teams, many sports medicine physicians are unfamiliar with the epidemiology of this pathogen. It is spread via person-to-person contact and is harbored within the anterior nares and on the skin of carriers. Outbreaks of community-acquired methicillin-resistant Staphylococcus aureus soft tissue infection are not treated by traditional ß-lactam antibiotics, and they can be difficult to eradicate. Such infections have been associated with significant morbidity, with up to 70% of involved team members requiring hospitalization and intravenous antibiotics. A thorough understanding of community-acquired methicillin-resistant Staphylococcus aureus is essential for the sports medicine physician to properly identify, treat, and control infectious outbreaks. [ABSTRACT FROM AUTHOR]

Removal of the meniscus is associated with later degenerative changes in the postoperative knee. Treatment of patients who present with osteoarthritis (OA) post-meniscectomy should be individualized according to symptoms and findings. Effective diagnostic evaluation requires use of the proper imaging modalities. Localization and description of the pain are important indicators of degenerative arthritis. Nonoperative interventions, including physical therapy, lifestyle modifications, orthoses, and injectable hyaluronate therapy, have been proved to be effective. Safe and effective oral pharmacologic treatments include acetaminophen, NSAIDs, and glucosamine and chondroitin sulfate. Surgical options include arthroscopic debridement and meniscal allograft transplantation. The surgeon's goal is to preserve meniscal tissue and to slow the progression of OA. [ABSTRACT FROM AUTHOR]

Background: The evaluation and management of knee dislocations remain variable and controversial. The purpose of this study was to describe our method of surgical treatment of knee dislocations with use of a standardized protocol and to report the clinical results.Methods: Forty-seven consecutive patients presented with an occult (reduced) or grossly dislocated knee. Fourteen of these patients were not included in this series because of confounding variables: four had an open knee dislocation, five had vascular injury requiring repair, three were treated with external fixation, and two had associated injury. The remaining thirty-three patients underwent surgical treatment for the knee dislocation with our standard approach. Anatomical repair and/or replacement was performed with fresh-frozen allograft tissue. Thirty-one of the thirty-three patients returned for subjective and objective evaluation with use of four different knee-rating scales at a minimum of twenty-four months after the operation.Results: Nineteen of the thirty-one patients were treated acutely (less than three weeks after the injury) and twelve, chronically. The mean Lysholm score was 91 points for the acutely reconstructed knees and 80 points for the chronically reconstructed knees. The Knee Outcome Survey Activities of Daily Living scores averaged 91 points for the acutely reconstructed knees and 84 points for the chronically reconstructed knees. The Knee Outcome Survey Sports Activity scores averaged 89 points for the acutely reconstructed knees and 69 points for the chronically reconstructed knees. According to the Meyers ratings, twenty-three patients had an excellent or good score and eight had a fair or poor score. Sixteen of the nineteen acutely reconstructed knees and seven of the twelve chronically reconstructed knees were given an excellent or good Meyers score. The average loss of extension was 1 degrees , and the average loss of flexion was 12 degrees . There was no difference in the range of motion between the acutely and chronically treated patients. Four acutely reconstructed knees required manipulation because of loss of flexion. Laxity tests demonstrated consistently improved stability in all patients, with more predictable results in the acutely treated patients.Conclusions: Surgical treatment of the knee dislocations in our series provided satisfactory subjective and objective outcomes at two to six years postoperatively. The patients who were treated acutely had higher subjective scores and better objective restoration of knee stability than did patients treated three weeks or more after the injury. Nearly all patients were able to perform daily activities with few problems. However, the ability of patients to return to high-demand sports and strenuous manual labor was less predictable. [ABSTRACT FROM AUTHOR]

BACKGROUND: The measurement of anterior or posterior tibial translation depends on the existence of a repeatable and accurate reference position of the knee from which the corresponding translation is measured. HYPOTHESIS: Clinical measurements of posterior tibial translation alone do not accurately reflect the laxity of posterior cruciate ligament-reconstructed knees. STUDY DESIGN: Controlled laboratory study. METHODS: Ten human cadaveric knees were tested by using a robotic/universal force-moment sensor testing system. The reference positions and the resulting kinematics in response to a 134-N anterior-posterior tibial load were determined for the intact and reconstructed knees. Posterior cruciate ligament reconstruction was performed with the graft tensioned and fixed at two different positions: 1) 90 degrees of knee flexion with a 134-N anterior tibial load and 2) full extension with no load. RESULTS: Posterior cruciate ligament reconstruction with graft fixation at full extension with no load resulted in anterior shift of the reference position by 1.5 to 3.2 mm. The reconstruction resulted in an overconstrained knee with significantly decreased total anterior-posterior translation of 2.6 to 3.2 mm. However, the posterior tibial translation measured was not significantly different from that of the intact knee. Posterior cruciate ligament reconstruction with graft fixation performed at 90 degrees of flexion with a 134-N anterior tibial load resulted in kinematics similar to those of the intact knee. CONCLUSION: Posterior tibial translations that are measured clinically can be misleading because the reference position of the knee can be shifted significantly after posterior cruciate ligament reconstruction. Clinical Relevance: The measurement of total anterior-posterior translation may be a more accurate way to assess kinematics of the reconstructed knee. [ABSTRACT FROM AUTHOR]

Over the past thirty years, the subspecialty of sports medicine has evolved into a major component of the practice of orthopaedic surgery. Since its genesis in the early 1970s, sports medicine has evolved from the province of a small group of orthopaedists covering athletic teams into a major body of knowledge fueled by clinicians, scientists, and industry. Well-established educational curricula defining and prioritizing all areas of sports medicine now exist at the resident, fellowship, and subspecialtysociety levels.The purpose of this article is to review and to put into perspective recent scientific and educational advancements in sports medicine. This overview is based on papers presented in 2000 at both the annual and subspecialty meetings of the American Orthopaedic Society for Sports Medicine (AOSSM), the Arthroscopy Association of North America (AANA), the Orthopaedic Research Society (ORS), and the American Academy of Orthopaedic Surgeons (AAOS). Papers published from September 1999 through August 2000 in the American Journal of Sports Medicine (six volumes), Arthroscopy (twelve volumes), and The Journal of Bone and Joint Surgery (twelve volumes) are reviewed, and their major contributions to orthopaedic sports medicine are summarized. This general overview of papers and presentations is followed by a summary of new developments in the study of the knee and shoulder as well as in other aspects of sports medicine, a discussion of emerging technologies in basic-science research, and an update on educational and socioeconomic issues. [ABSTRACT FROM AUTHOR]

We hypothesized that posterior cruciate ligament reconstructions are often compromised by associated injuries to the posterolateral structures. Therefore, we evaluated a posterior cruciate ligament reconstruction in isolated and combined injury models using a robotic/universal force-moment sensor testing system. The resulting knee kinematics and the in situ forces in the native and reconstructed posterior cruciate ligament were determined under four external loading conditions. In the isolated injury model, reconstruction reduced posterior tibial translation to within 1.5+/-1.3 to 2.4+/-1.4 mm of the intact knee at 30 degrees and 90 degrees under a 134-N posterior tibial load. In the combined injury model, deficiency of the posterolateral structures increased posterior tibial translation of the reconstructed knee by 6.0+/-2.7 mm at 30 degrees and 4.6+/-1.5 mm at 90 degrees of flexion. External rotation increased up to 14 degrees while varus rotation increased up to 7 degrees. In situ forces in the posterior cruciate ligament graft also increased significantly (by 22% to 150%) for all loading conditions. Our results demonstrate that a graft that restores knee kinematics for an isolated posterior cruciate ligament deficiency is rendered ineffective and may be overloaded if the posterolateral structures are deficient. Therefore, surgical reconstruction of both structures is recommended in the setting of a combined injury. [ABSTRACT FROM AUTHOR]

To investigate the effect of simulated contraction of the popliteus muscle on the in situ forces in the posterior cruciate ligament and on changes in knee kinematics, we studied 10 human cadaveric knees (donor age, 58 to 89 years) using a robotic manipulator/universal force moment sensor system. Under a 110-N posterior tibial load (simulated posterior drawer test), the kinematics of the intact knee and the in situ forces in the ligament were determined. The test was repeated with the addition of a 44-N load to the popliteus muscle. The posterior cruciate ligament was then sectioned and the knee was subjected to the same tests. The additional popliteus muscle load significantly reduced the in situ forces in the ligament by 9% to 36% at 90 degrees and 30 degrees of flexion, respectively. No significant effects on posterior tibial translation of the intact knee were found. However, in the ligament-deficient knee, posterior tibial translation was reduced by up to 36% of the translation caused by ligament transection. A coupled internal tibial rotation of 2 degrees to 4 degrees at 60 degrees to 90 degrees of knee flexion was observed in both the intact and ligament-deficient knees when the popliteus muscle load was added. Our results indicate that the popliteus muscle shares the function of the posterior cruciate ligament in resisting posterior tibial loads and can contribute to knee stability when the ligament is absent. [ABSTRACT FROM AUTHOR]

Improved basic science data on the anatomy and biomechanics of the human posterior cruciate ligament have provided the orthopaedic surgeon with new information on which to base treatment decisions. Injuries to the posterior cruciate ligament are reported to comprise approximately 3% of all knee ligament injuries in the general population and as high as 37% in an emergency department setting. While the diagnosis of a posterior cruciate ligament injury can often be made with a physical examination, ancillary studies such as radiographs and magnetic resonance images can be very helpful in detecting associated ligament and bony injuries. In general, most partial (grades I and II) posterior cruciate ligament injuries can be treated nonoperatively. However, surgical reconstruction is usually recommended for those posterior cruciate ligament injuries that occur in combination with other structures. In this review, current surgical techniques of posterior cruciate ligament reconstruction based on anatomic and biomechanical studies will be discussed. [ABSTRACT FROM AUTHOR]

We examined the in situ forces in the posterior cruciate ligament as well as the force distribution between its anterolateral and posteromedial bundles. Using a robotic manipulator in conjunction with a universal force-moment sensor system, we applied posterior tibial loads from 22 to 110 N to the joint at 0 degrees to 90 degrees of knee flexion. The magnitude of the in situ force in the posterior cruciate ligament and its bundles was significantly affected by knee flexion angle and posterior tibial loading. In situ forces in the posterior cruciate ligament ranged from 6.1 +/- 6.0 N under a 22-N posterior tibial load at 0 degree of knee flexion to 112.3 +/- 28.5 N under a 110-N load at 90 degrees. The force in the posteromedial bundle reached a maximum of 67.9 +/- 31.5 N at 90 degrees of knee flexion, and the force in the anterolateral bundle reached a maximum of 47.8 +/- 23.0 N at 60 degrees of knee flexion under a 110-N load. No significant differences existed between the in situ forces in the two bundles at any knee flexion angle. This study provides insight into the knee flexion angle at which each bundle of the posterior cruciate ligament experiences the highest in situ forces under posterior tibial loading. This information can help guide us in more accurate graft placement, fixation, and tensioning, and serve as an assessment of graft performance. [ABSTRACT FROM AUTHOR]

To study the structural and functional properties of the human posterior cruciate ligament complex, we measured the cross-sectional shape and area of the anterior cruciate, posterior cruciate, and meniscofemoral ligaments in eight cadaveric knees. The posterior cruciate ligament increased in cross-sectional area from tibia to femur, and the anterior cruciate ligament area decreased from tibia to femur. The meniscofemoral ligaments did not change shape in their course from the lateral meniscus to their femoral insertions. The posterior cruciate ligament cross-sectional area was approximately 50% and 20% greater than that of the anterior cruciate ligament at the femur and tibia, respectively. The meniscofemoral ligaments averaged approximately 22% of the entire cross-sectional area of the posterior cruciate ligament. The insertion sites of the anterior and posterior cruciate ligaments were evaluated. The insertion sites of the anterior and posterior cruciate ligaments were 300% to 500% larger than the cross-section of their respective midsubstances. We determined, through transmission electron microscopy, fibril size within the anterior and posterior cruciate ligament complex from the femur to the tibia. The posterior cruciate ligament becomes increasingly larger from the tibial to the femoral insertions, and the anterior cruciate ligament becomes smaller toward the femoral insertion. We evaluated the biomechanical properties of the femur-posterior cruciate ligament-tibia complex using 14 additional human cadaveric knees. The posterior cruciate ligament was divided into two functional components: the anterolateral, which is taut in knee flexion, and the posteromedial, which is taut in knee extension. The anterolateral component had a significantly greater linear stiffness and ultimate load than both the posteromedial component and meniscofemoral ligaments. The anterolateral component and the meniscofemoral ligaments displayed similar elastic moduli, which were both significantly greater than that of the posteromedial component. [ABSTRACT FROM AUTHOR]

The authors conducted a study to determine if the long head of the biceps muscle and its attachment at the superior glenoid labrum play a role in stability of the shoulder in an overhead position. Their study used a dynamic cadaveric shoulder model that simulated the forces of the rotator cuff and long head of biceps muscles as the glenohumeral joint was abducted and externally rotated. Their data suggest that the long head of the biceps muscle contributes to anterior stability of the glenohumeral joint by increasing the shoulder's resistance to torsional forces in the vulnerable abducted and externally rotated position. The biceps muscle also helps to diminish the stress placed on the inferior glenohumeral ligament. Detachment of the superior glenoid labrum is detrimental to anterior shoulder stability as it decreases the shoulder's resistance to torsion and places a greater magnitude of strain on the inferior glenohumeral ligament. [ABSTRACT FROM AUTHOR]

Even among the active middle-aged population, knee arthritis is a common condition that can greatly decrease quality of life. The 45 degree flexion weight-bearing radiograph, a crucial diagnostic step, can show joint space loss. Each patient must be treated individually, but conservative treatment with medication, activity modification, exercise, physical therapy, braces, and joint injections may be effective for long periods. Operative modalities include joint arthroscopy and reconstructive procedures such as osteotomy and joint arthroplasty. In injured knees, meniscus and cartilage transplants may prevent the development or progression of osteoarthritis. Total knee arthroplasty should be considered in active patients only when all other options have been exhausted. [ABSTRACT FROM AUTHOR]

We used the information on in situ forces provided by robotics to compare two methods of posterior cruciate ligament graft fixation. Twenty porcine knees were studied using robotic technology to determine and repeat intact, deficient, and reconstructed knee motion under 110 N of posterior tibial loading at 30 degrees, 60 degrees, and 90 degrees of knee flexion. Reconstruction was performed using a bone-patellar tendon-bone graft with the distal end of the graft placed in the posterolateral aspect of the posterior cruciate ligament tibial insertion. Specimens were separated into two groups based on the femoral fixation site: the proximal or anterior aspect of the femoral insertion. Repetition of knee motion allowed measurement of the force in the intact posterior cruciate ligament and graft using the principle of superposition. The forces in the graft and the intact ligament provided additional information to evaluate graft performance. Force in the intact posterior cruciate ligament was significantly greater at 90 degrees than at 30 degrees and 60 degrees of knee flexion. The forces in both graft types were significantly lower than those of the posterior cruciate ligament, but the force in the anteriorly placed graft was significantly greater at 90 degrees than at 30 degrees and 60 degrees of knee flexion, similar to the intact posterior cruciate ligament. Thus, the anteriorly placed graft had a more physiologic increase in tension with knee flexion, when the joint provided less restraint. [ABSTRACT FROM AUTHOR]

We assessed the effectiveness of a new suture anchor that has been designed to anchor sutures into a blind, straight hole drilled in bone. The strength of fixation in glenoid bone is 67 N for the No. 0 anchor and suture, and 82 N for the No. 2 device with suture. During 1988 and 1989, 32 patients underwent a modified Bankart reconstruction for recurrent anterior glenohumeral instability at two centers as part of a prospective study of this modified technique. There were no complications as a result of the technique. The four surgeons involved agreed that the suture anchor simplified the procedure. Seventeen patients have been reviewed, with more than 1 year followup. Ninety-four percent had good to excellent results according to the Bankart rating scale. There was one recurrent dislocation in a football player. [ABSTRACT FROM AUTHOR]

Background: Revision anterior cruciate ligament (ACL) reconstruction has been documented to have inferior outcomes compared with primary ACL reconstruction. The reasons why remain unknown., Purpose: To determine whether surgical factors performed at the time of revision ACL reconstruction can influence a patient's outcome at 6-year follow-up., Study Design: Cohort study; Level of evidence, 2., Methods: Patients who underwent revision ACL reconstruction were identified and prospectively enrolled between 2006 and 2011. Data collected included baseline patient characteristics, surgical technique and pathology, and a series of validated patient-reported outcome instruments: Knee injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC) subjective form, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Marx activity rating score. Patients were followed up for 6 years and asked to complete the identical set of outcome instruments. Regression analysis was used to control for baseline patient characteristics and surgical variables to assess the surgical risk factors for clinical outcomes 6 years after surgery., Results: A total of 1234 patients were enrolled (716 men, 58%; median age, 26 years), and 6-year follow-up was obtained on 79% of patients (980/1234). Using an interference screw for femoral fixation compared with a cross-pin resulted in significantly better outcomes in 6-year IKDC scores (odds ratio [OR], 2.2; 95% CI, 1.2-3.9; P = .008) and KOOS sports/recreation and quality of life subscale scores (OR range, 2.2-2.7; 95% CI, 1.2-4.8; P < .01). Use of an interference screw compared with a cross-pin resulted in a 2.6 times less likely chance of having a subsequent surgery within 6 years. Use of an interference screw for tibial fixation compared with any combination of tibial fixation techniques resulted in significantly improved scores for IKDC (OR, 1.96; 95% CI, 1.3-2.9; P = .001); KOOS pain, activities of daily living, and sports/recreation subscales (OR range, 1.5-1.6; 95% CI, 1.0-2.4; P < .05); and WOMAC pain and activities of daily living subscales (OR range, 1.5-1.8; 95% CI, 1.0-2.7; P < .05). Use of a transtibial surgical approach compared with an anteromedial portal approach resulted in significantly improved KOOS pain and quality of life subscale scores at 6 years (OR, 1.5; 95% CI, 1.02-2.2; P ≤ .04)., Conclusion: There are surgical variables at the time of ACL revision that can modify clinical outcomes at 6 years. Opting for a transtibial surgical approach and choosing an interference screw for femoral and tibial fixation improved patients' odds of having a significantly better 6-year clinical outcome in this cohort., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This project was funded by grant No. 5R01-AR060846 from the National Institutes of Health/National Institute of Arthritis and Musculoskeletal and Skin Diseases. All author disclosures are listed in the Appendix (available in the online version of this article). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Multiple ligament knee injuries (MLKIs) represent a spectrum of injury patterns that are often associated with concomitant musculoskeletal and neurovascular injuries, complex treatment, and postoperative complications. However, there has not been high-level evidence describing the presentation and treatment of MLKIs. The purpose of this multicenter retrospective study was to describe characteristics of MLKIs, their management, and related complications using a pathoanatomic MLKI classification system based on the Schenck Knee Dislocation classification system., Methods: This review identified and analyzed MLKIs that occurred between 2011 and 2015. Cases with an MLKI were included in this study if there was a complete tear of ≥2 ligaments and at least 1 ligament was repaired or reconstructed. Cases in which a ligament was deemed clinically incompetent due to a partial ligament tear and required surgical repair or reconstruction were considered equivalent to grade-III tears for inclusion and classification. Demographic information, the mechanism of injury, times from injury to presentation to an orthopaedic surgeon and to surgery, the ligament injury pattern, associated injuries, surgical procedures, and complications were captured. Data were analyzed descriptively., Results: A total of 773 individuals from 14 centers who underwent surgery for an MLKI were reviewed. The mean age of the individuals was 30.5 ± 12.7 years, and 74.2% were male. The most common mechanism involved sports (43.2%). The median time from injury to presentation to the orthopaedic surgeon was 11 days (interquartile range [IQR], 3 to 48 days), and the time to initial ligament surgery was 64 days (IQR, 23 to 190 days). While the most common injury patterns were an anterior cruciate ligament tear combined with either a medial-sided (MLK 1-AM, 20.7%) or lateral-sided (MLK 1-AL, 23.2%) injury, one-third (34.7%) were bicruciate injuries. Associated injuries most often involved menisci (55.6%), nerves (18.5%) and tendons (15.6%). The method of surgical intervention (repair versus reconstruction), external fixator use, and staging of procedures varied by MLKI classification. Loss of motion (11.4%) was the most common postoperative complication., Conclusions: A better understanding of the clinical characteristics and management of the various MLKI patterns can be used to support clinical decision-making and individualized treatment of these complex injuries, and may ultimately lead to enhanced outcomes and reduced associated risks., Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article ( http://links.lww.com/JBJS/H440 )., (Copyright © 2023 Written work prepared by employees of the Federal Government as part of their official duties is, under the United States Copyright Act, a “work of the United States Government” for which copyright protection under that Act is not available. As such, copyright protection does not extend to the contributions of employees of the Federal Government prepared as part of their employment.)

Background: Meniscal and chondral damage is common in the patient undergoing revision anterior cruciate ligament (ACL) reconstruction., Purpose: To determine if meniscal and/or articular cartilage pathology at the time of revision ACL surgery significantly influences a patient's outcome at 6-year follow-up., Study Design: Cohort study; Level of evidence, 3., Methods: Patients undergoing revision ACL reconstruction were prospectively enrolled between 2006 and 2011. Data collection included baseline demographics, surgical technique, pathology, treatment, and scores from 4 validated patient-reported outcome instruments: International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Marx Activity Rating Scale. Patients were followed up at 6 years and asked to complete the identical set of outcome instruments. Regression analysis assessed the meniscal and articular cartilage pathology risk factors for clinical outcomes 6 years after revision ACL reconstruction., Results: An overall 1234 patients were enrolled (716 males, 58%; median age, 26 years). Surgeons reported the pathology at the time of revision surgery in the medial meniscus (45%), lateral meniscus (36%), medial femoral condyle (43%), lateral femoral condyle (29%), medial tibial plateau (11%), lateral tibial plateau (17%), patella (30%), and trochlea (21%). Six-year follow-up was obtained on 79% of the sample (980/1234). Meniscal pathology and articular cartilage pathology (medial femoral condyle, lateral femoral condyle, lateral tibial plateau, trochlea, and patella) were significant drivers of poorer patient-reported outcomes at 6 years (IKDC, KOOS, WOMAC, and Marx). The most consistent factors driving outcomes were having a medial meniscal excision (either before or at the time of revision surgery) and patellofemoral articular cartilage pathology. Six-year Marx activity levels were negatively affected by having either a repair/excision of the medial meniscus (odds ratio range, 1.45-1.72; P ≤ .04) or grade 3-4 patellar chondrosis (odds ratio, 1.72; P = .04). Meniscal pathology occurring before the index revision surgery negatively affected scores on all KOOS subscales except for sports/recreation ( P < .05). Articular cartilage pathology significantly impaired all KOOS subscale scores ( P < .05). Lower baseline outcome scores, higher body mass index, being a smoker, and incurring subsequent surgery all significantly increased the odds of reporting poorer clinical outcomes at 6 years., Conclusion: Meniscal and chondral pathology at the time of revision ACL reconstruction has continued significant detrimental effects on patient-reported outcomes at 6 years after revision surgery.

Objectives: Knee dislocations (KDs) are complex injuries defined as incongruity of the tibiofemoral joint, which leads to tears of two or more of the main stabilising knee ligaments, and they are often associated with damage to surrounding soft tissue or neurovascular structures. A classification system for these injuries should be simple and reproducible and allow communication among surgeons for surgical planning and outcome prediction. The aim of this study was to formulate a list of factors, prioritised by high-volume knee surgeons, that should be included in a KD classification system., Methods: A global panel of orthopaedic knee surgery specialists participated in a Delphi process. The first survey employed 91 orthopaedic surgeons to generate a list of patient- and system-specific factors that should be included in a KD classification system that may affect surgical planning and outcomes. This list was subsequently prioritised by 27 identified experts (mean 15.3 years of experience) from Brazil (n = 9), USA (n = 6), South Africa (n = 4), India (n = 4), China (n = 2), and the United Kingdom (n = 2). The items were analysed to find factors that had at least 70% consensus for inclusion in a classification system., Results: Of the 12 factors identified, four (33%) achieved at least 70% consensus for inclusion in a classification system. The factors deemed critical for inclusion in a classification system included vascular injuries (89%), common peroneal nerve injuries (78%), number of torn ligaments (78%), and open injuries (70%)., Conclusion: Consensus for inclusion of various factors in a KD classification system was not easily achieved. The wide geographic distribution of participants provides diverse insight and makes the results of the study globally applicable. The most important factors to include in a classification system as determined by the Delphi technique were vascular injuries, common peroneal nerve injuries, number of torn ligaments, and open injuries. To date, the Schenck anatomic classification system most accurately identifies these patient variables with the addition of open injury classification. The authors propose to update the Schenck classification system with the inclusion of open injuries as an additional modifier, although this is only a small step in updating the classification, and further studies should evaluate the inclusion of more advanced imaging modalities. Future research should focus on integrating these factors into useful existing classification systems that are predictive of surgical treatment and patient outcomes., Competing Interests: Declaration of competing interest D.CW. is a member of the ISAKOS Board of Directors. The other authors have no competing interest to declare., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: Lytic or malpositioned tunnels may require bone grafting during revision anterior cruciate ligament reconstruction (rACLR) surgery. Patient characteristics and effects of grafting on outcomes after rACLR are not well described., Purpose: To describe preoperative characteristics, intraoperative findings, and 2-year outcomes for patients with rACLR undergoing bone grafting procedures compared with patients with rACLR without grafting., Study Design: Cohort study; Level of evidence, 3., Methods: A total of 1234 patients who underwent rACLR were prospectively enrolled between 2006 and 2011. Baseline revision and 2-year characteristics, surgical technique, pathology, treatment, and patient-reported outcome instruments (International Knee Documentation Committee [IKDC], Knee injury and Osteoarthritis Outcome Score [KOOS], Western Ontario and McMaster Universities Osteoarthritis Index, and Marx Activity Rating Scale [Marx]) were collected, as well as subsequent surgery information, if applicable. The chi-square and analysis of variance tests were used to compare group characteristics., Results: A total of 159 patients (13%) underwent tunnel grafting-64 (5%) patients underwent 1-stage and 95 (8%) underwent 2-stage grafting. Grafting was isolated to the femur in 31 (2.5%) patients, the tibia in 40 (3%) patients, and combined in 88 patients (7%). Baseline KOOS Quality of Life (QoL) and Marx activity scores were significantly lower in the 2-stage group compared with the no bone grafting group ( P ≤ .001). Patients who required 2-stage grafting had more previous ACLRs ( P < .001) and were less likely to have received a bone-patellar tendon-bone or a soft tissue autograft at primary ACLR procedure ( P ≤ .021) compared with the no bone grafting group. For current rACLR, patients undergoing either 1-stage or 2-stage bone grafting were more likely to receive a bone-patellar tendon-bone allograft ( P ≤ .008) and less likely to receive a soft tissue autograft ( P ≤ .003) compared with the no bone grafting group. At 2-year follow-up of 1052 (85%) patients, we found inferior outcomes in the 2-stage bone grafting group (IKDC score = 68; KOOS QoL score = 44; KOOS Sport/Recreation score = 65; and Marx activity score = 3) compared with the no bone grafting group (IKDC score = 77; KOOS QoL score = 63; KOOS Sport/Recreation score = 75; and Marx activity score = 7) ( P ≤ .01). The 1-stage bone graft group did not significantly differ compared with the no bone grafting group., Conclusion: Tunnel bone grafting was performed in 13% of our rACLR cohort, with 8% undergoing 2-stage surgery. Patients treated with 2-stage grafting had inferior baseline and 2-year patient-reported outcomes and activity levels compared with patients not undergoing bone grafting. Patients treated with 1-stage grafting had similar baseline and 2-year patient-reported outcomes and activity levels compared with patients not undergoing bone grafting.

Abstract: The ability to train an orthopaedic resident in all aspects of orthopaedics in 5 years has become increasingly difficult due to the growth in knowledge and techniques, work-hour restrictions, and reduced resident autonomy. It has become nearly universal for our residents to complete at least 1 subspecialty fellowship prior to entering practice. In some subspecialties, the skills necessary to practice competently have become difficult to master. Simply adding to the current length of training may not address these issues effectively and would add to the economic cost of residency training. Novel training pathways that allow residents to focus earlier and in greater depth on their intended subspecialty while maintaining general orthopaedic competencies can be created without lengthening training. It is time to initiate discussions about these possibilities., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJS/G918)., (Copyright © 2022 by The Journal of Bone and Joint Surgery, Incorporated.)

Background: Patients with anterior cruciate ligament (ACL) revision report lower outcome scores on validated knee questionnaires postoperatively compared to cohorts with primary ACL reconstruction. In a previously active population, it is unclear if patient-reported outcomes (PROs) are associated with a return to activity (RTA) or vary by sports participation level (higher level vs. recreational athletes)., Hypotheses: Individual RTA would be associated with improved outcomes (ie, decreased knee symptoms, pain, function) as measured using validated PROs. Recreational participants would report lower PROs compared with higher level athletes and be less likely to RTA., Study Design: Cohort study; Level of evidence, 2., Methods: There were 862 patients who underwent a revision ACL reconstruction (rACLR) and self-reported physical activity at any level preoperatively. Those who did not RTA reported no activity 2 years after revision. Baseline data included patient characteristics, surgical history and characteristics, and PROs: International Knee Documentation Committee questionnaire, Marx Activity Rating Scale, Knee injury and Osteoarthritis Outcome Score, and the Western Ontario and McMaster Universities Osteoarthritis Index. A binary indicator was used to identify patients with same/better PROs versus worse outcomes compared with baseline, quantifying the magnitude of change in each direction, respectively. Multivariable regression models were used to evaluate risk factors for not returning to activity, the association of 2-year PROs after rACLR surgery by RTA status, and whether each PRO and RTA status differed by participation level., Results: At 2 years postoperatively, approximately 15% did not RTA, with current smokers (adjusted odds ratio [aOR] = 3.3; P = .001), female patients (aOR = 2.9; P < .001), recreational participants (aOR = 2.0; P = .016), and those with a previous medial meniscal excision (aOR = 1.9; P = .013) having higher odds of not returning. In multivariate models, not returning to activity was significantly associated with having worse PROs at 2 years; however, no clinically meaningful differences in PROs at 2 years were seen between participation levels., Conclusion: Recreational-level participants were twice as likely to not RTA compared with those participating at higher levels. Within a previously active cohort, no RTA was a significant predictor of lower PROs after rACLR. However, among patients who did RTA after rACLR, approximately 20% reported lower outcome scores. Most patients with rACLR who were active at baseline improved over time; however, patients who reported worse outcomes at 2 years had a clinically meaningful decline across all PROs.

Background: Although graft choice may be limited in the revision setting based on previously used grafts, most surgeons believe that graft choice for anterior cruciate ligament (ACL) reconstruction is an important factor related to outcome., Hypothesis: In the ACL revision setting, there would be no difference between autograft and allograft in rerupture rate and patient-reported outcomes (PROs) at 6-year follow-up., Study Design: Cohort study; Level of evidence, 2., Methods: Patients who had revision surgery were identified and prospectively enrolled in this cohort study by 83 surgeons over 52 sites. Data collected included baseline characteristics, surgical technique and pathology, and a series of validated PRO measures. Patients were followed up at 6 years and asked to complete the identical set of PRO instruments. Incidence of additional surgery and reoperation because of graft failure were also recorded. Multivariable regression models were used to determine the predictors (risk factors) of PROs, graft rerupture, and reoperation at 6 years after revision surgery., Results: A total of 1234 patients including 716 (58%) men were enrolled. A total of 325 (26%) underwent revision using a bone-patellar tendon-bone (BTB) autograft; 251 (20%), soft tissue autograft; 289 (23%), BTB allograft; 302 (25%), soft tissue allograft; and 67 (5%), other graft. Questionnaires and telephone follow-up for subsequent surgery information were obtained for 809 (66%) patients, while telephone follow-up was only obtained for an additional 128 patients for the total follow-up on 949 (77%) patients. Graft choice was a significant predictor of 6-year Marx Activity Rating Scale scores ( P = .024). Specifically, patients who received a BTB autograft for revision reconstruction had higher activity levels than did patients who received a BTB allograft (odds ratio [OR], 1.92; 95% CI, 1.25-2.94). Graft rerupture was reported in 5.8% (55/949) of patients by their 6-year follow-up: 3.5% (16/455) of patients with autografts and 8.4% (37/441) of patients with allografts. Use of a BTB autograft for revision resulted in patients being 4.2 times less likely to sustain a subsequent graft rupture than if a BTB allograft were utilized ( P = .011; 95% CI, 1.56-11.27). No significant differences were found in graft rerupture rates between BTB autograft and soft tissue autografts ( P = .87) or between BTB autografts and soft tissue allografts ( P = .36). Use of an autograft was found to be a significant predictor of having fewer reoperations within 6 years compared with using an allograft ( P = .010; OR, 0.56; 95% CI, 0.36-0.87)., Conclusion: BTB and soft tissue autografts had a decreased risk in graft rerupture compared with BTB allografts. BTB autografts were associated with higher activity level than were BTB allografts at 6 years after revision reconstruction. Surgeons and patients should consider this information when choosing a graft for revision ACL reconstruction.

Infection is a rare occurrence after revision anterior cruciate ligament reconstruction (rACLR). Because of the low rates of infection, it has been difficult to identify risk factors for infection in this patient population. The purpose of this study was to report the rate of infection following rACLR and assess whether infection is associated with patient- and surgeon-dependent risk factors. We reviewed two large prospective cohorts to identify patients with postoperative infections following rACLR. Age, sex, body mass index (BMI), smoking status, history of diabetes, and graft choice were recorded for each patient. The association of these factors with postoperative infection following rACLR was assessed. There were 1423 rACLR cases in the combined cohort, with 9 (0.6%) reporting postoperative infections. Allografts had a higher risk of infection than autografts (odds ratio, 6.8; 95% CI, 0.9-54.5; p = .045). Diabetes (odds ratio, 28.6; 95% CI, 5.5-149.9; p = .004) was a risk factor for infection. Patient age, sex, BMI, and smoking status were not associated with risk of infection after rACLR., (© 2020 Orthopaedic Research Society. Published by Wiley Periodicals LLC.)

This study aims to evaluate relationships among multiple ligament knee injury (MLKI) patterns as classified according to the knee dislocation (KD) classification and the types of surgical management pursued. We hypothesized that the KD classification would not be predictive of the types of surgical management, and that categorizing injuries according to additional injury features such as structure, chronicity, grade, and topographic location would be predictive of the types of surgical management. This is a Retrospective cohort study. This study was conducted at a level I trauma center with a 150-mile coverage radius. Query of our billing database was performed using combinations of 43 billing codes (International Classification of Diseases [ICD] 9, ICD-10, and Current Procedural Terminology) to identify patients from 2011 to 2015 who underwent operative management for MLKIs. There were operative or nonoperative treatment for individual ligamentous injuries, repair, or reconstruction of individual ligamentous injuries, and staging or nonstaging or nonstaging of each surgical procedure. The main outcome was the nature and timing of clinical management for specific ligamentous injury patterns. In total, 287 patients were included in this study; there were 199 males (69.3%), the mean age was 30.2 years (SD: 14.0), and the mean BMI was 28.8 kg/m 2 (SD: 7.4). There were 212 injuries (73.9%) categorized as either KD-I or KD-V. The KD classification alone was not predictive of surgery timing, staging, or any type of intervention for any injured ligament ( p  > 0.05). Recategorization of injury patterns according to structure, chronicity, grade, and location revealed the following: partial non-ACL injuries were more frequently repaired primarily ( p  < 0.001), distal medial-sided injuries were more frequently treated operatively than proximal medial-sided injuries (odds ratio [OR] = 24.7; p <0.0001), and staging was more frequent for combined PCL-lateral injuries (OR = 1.3; p  = 0.003) and nonavulsive fractures (OR = 1.2; p  = 0.0009). The KD classification in isolation was not predictive of any surgical management strategy. Surgical management was predictable when specifying the grade and topographic location of each ligamentous injury. This is a Level IV, retrospective cohort study., Competing Interests: One or more of the authors have received research funding outside and separate from this work. W.R.L. is a consultant for Arthrex Inc. and DonJoy Orthopaedics. All authors certify that they have no commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article. R.J.W. was the recipient of the 2017 Young Investigator Award from the Musculoskeletal Transplant Foundation and received textbook royalties from Springer International. No conflicts are reported for the remaining authors., (Thieme. All rights reserved.)

Athletic team coverage experience varies widely across orthopedic surgery residency programs in the United States. There is a paucity of literature regarding whether serving as a team physician contributes to resident education and whether it can be performed within the bounds of current work-hour restrictions. Residents consider coverage of high school football games a valuable educational experience that does not adversely affect their 80-hour work week. Sixty-one orthopedic residents who served as high school football team physicians as part of their residency curriculum completed an 11-question survey. Responses ranged from strongly agree (1) to strongly disagree (5) on a Likert scale. The majority of residents agreed that serving as a team physician was an overall valuable experience (85%), that it enhanced their orthopedic sports medicine education (89%), and that it increased their awareness of the role played by athletic trainers (97%). The majority of respondents disagreed only with the statement that serving as a team physician had negatively affected their 80-hour work week (54%), and an additional 26% neither agreed nor disagreed. The vast majority of participating orthopedic residents consider high school football team coverage a valuable experience that enhances education and can be performed within work-hour limitations. [Orthopedics. 2020;43(6):e574-e578.]., (Copyright 2020, SLACK Incorporated.)

Background: The timing of return to play after anterior cruciate ligament (ACL) reconstruction is still controversial due to uncertainty of true ACL graft state at the time of RTP. Recent work utilizing ultra-short echo T2* (UTE-T2*) magnetic resonance imaging (MRI) as a scanner-independent method to objectively and non-invasively assess the status of in vivo ACL graft remodeling has produced promising results., Purpose/hypothesis: The purpose of this study was to prospectively and noninvasively investigate longitudinal changes in T2* within ACL autografts at incremental time points up to 12 months after primary ACL reconstruction in human patients. We hypothesized that (1) T2* would increase from baseline and initially exceed that of the intact contralateral ACL, followed by a gradual decline as the graft undergoes remodeling, and (2) remodeling would occur in a region-dependent manner., Study Design: Case series; Level of evidence, 4., Methods: Twelve patients (age range, 14-45 years) who underwent primary ACL reconstruction with semitendinosus tendon or bone-patellar tendon-bone autograft (with or without meniscal repair) were enrolled. Patients with a history of previous injury or surgery to either knee were excluded. Patients returned for UTE MRI at 1, 3, 6, 9, and 12 months after ACL reconstruction. Imaging at 1 month included the contralateral knee. MRI pulse sequences included high-resolution 3-dimensional gradient echo sequence and a 4-echo T2-UTE sequence (slice thickness, 1 mm; repetition time, 20 ms; echo time, 0.3, 3.3, 6.3, and 9.3 ms). All slices containing the intra-articular ACL were segmented from high-resolution sequences to generate volumetric regions of interest (ROIs). ROIs were divided into proximal/distal and core/peripheral sub-ROIs using standardized methods, followed by voxel-to-voxel registration to generate T2* maps at each time point. This process was repeated by a second reviewer for interobserver reliability. Statistical differences in mean T2* values and mean ratios of T2* inj /T2* intact (ie, injured knee to intact knee) among the ROIs and sub-ROIs were assessed using repeated measures and one-way analyses of variance. P < .05 represented statistical significance., Results: Twelve patients enrolled in this prospective study, 2 withdrew, and ultimately 10 patients were included in the analysis (n = 7, semitendinosus tendon; n = 3, bone-patellar tendon-bone). Interobserver reliability for T2* values was good to excellent (intraclass correlation coefficient, 0.84; 95% CI, 0.59-0.94; P < .001). T2* values increased from 5.5 ± 2.1 ms (mean ± SD) at 1 month to 10.0 ± 2.9 ms at 6 months ( P = .001), followed by a decline to 8.1 ± 2.0 ms at 12 months ( P = .129, vs 1 month; P = .094, vs 6 months). Similarly, mean T2* inj /T2* intact ratios increased from 62.8% ± 22.9% at 1 month to 111.1% ± 23.9% at 6 months ( P = .001), followed by a decline to 92.8% ± 29.8% at 12 months ( P = .110, vs 1 month; P = .086, vs 6 months). Sub-ROIs exhibited similar increases in T2* until reaching a peak at 6 months, followed by a gradual decline until the 12-month time point. There were no statistically significant differences among the sub-ROIs ( P > .05)., Conclusion: In this preliminary study, T2* values for ACL autografts exhibited a statistically significant increase of 82% between 1 and 6 months, followed by an approximate 19% decline in T2* values between 6 and 12 months. In the future, UTE-T2* MRI may provide unique insights into the condition of remodeling ACL grafts and may improve our ability to noninvasively assess graft maturity before return to play.

Background: Meniscal preservation has been demonstrated to contribute to long-term knee health. This has been a successful intervention in patients with isolated tears and tears associated with anterior cruciate ligament (ACL) reconstruction. However, the results of meniscal repair in the setting of revision ACL reconstruction have not been documented., Purpose: To examine the prevalence and 2-year operative success rate of meniscal repairs in the revision ACL setting., Study Design: Case-control study; Level of evidence, 3., Methods: All cases of revision ACL reconstruction with concomitant meniscal repair from a multicenter group between 2006 and 2011 were selected. Two-year follow-up was obtained by phone and email to determine whether any subsequent surgery had occurred to either knee since the initial revision ACL reconstruction. If so, operative reports were obtained, whenever possible, to verify the pathologic condition and subsequent treatment., Results: In total, 218 patients (18%) from 1205 revision ACL reconstructions underwent concurrent meniscal repairs. There were 235 repairs performed: 153 medial, 48 lateral, and 17 medial and lateral. The majority of these repairs (n = 178; 76%) were performed with all-inside techniques. Two-year surgical follow-up was obtained on 90% (197/218) of the cohort. Overall, the meniscal repair failure rate was 8.6% (17/197) at 2 years. Of the 17 failures, 15 were medial (13 all-inside, 2 inside-out) and 2 were lateral (both all-inside). Four medial failures were treated in conjunction with a subsequent repeat revision ACL reconstruction., Conclusion: Meniscal repair in the revision ACL reconstruction setting does not have a high failure rate at 2-year follow-up. Failure rates for medial and lateral repairs were both <10% and consistent with success rates of primary ACL reconstruction meniscal repair. Medial tears underwent reoperation for failure at a significantly higher rate than lateral tears.

Purpose: To quantify the effects of lateral extra-articular tenodesis (LET) on tibiofemoral compartment contact area and pressures, knee kinematics, and forces., Methods: Nine cadaveric knees were tested using a robotic testing system. Two loading conditions, (1) anterior tibial translational load coupled with axial compression and (2) internal tibial torque coupled with axial compression, were applied for each knee state at full extension and 30°, 60°, and 90° of knee flexion. Kinematic data was recorded for 3 knee states: anterolateral capsule (ALC) competent, ALC deficient, and post-LET using a 6-mm semitendinosus graft. In situ force in the anterior cruciate ligament (ACL) was quantified using the principle of superposition by comparing the change in force measured before and after the removal of the ALC. Contact area and pressures in each tibiofemoral compartment were measured by replaying kinematics after soft tissues were removed and pressure sensors were inserted., Results: In response to an anterior tibial translational load, mean contact area in the medial compartment decreased by 33.1% from the ALC-competent to post-LET knee states at 90° of knee flexion (P = .042). No significant differences in lateral compartment contact pressure were found between knee states. In situ force in the ACL in response to an anterior tibial translational load decreased by 43.4% and 50% from the ALC-deficient to post-LET knee states at 60° (P = .02) and 90° (P = .006). No significant difference in kinematics was observed between the ALC-competent and post-LET knee states in each of the loading conditions at all knee flexion angles (P > .05)., Conclusions: In this in vitro model, LET with a semitendinosus graft did not significantly overconstrain the knee or increase pressure in the lateral compartment. Additionally, LET reduced the in situ force in the ACL in the setting of ALC injury., Clinical Relevance: The lack of knee overconstraint without significant increases in lateral compartment pressures indicates that if an LET with semitendinosus graft is not overtensioned, accelerated degenerative changes in the lateral compartment may not be expected after this procedure., (Copyright © 2020 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Background: Augmentation of soft-tissue repairs with an autologous fibrin clot has been used clinically for nearly four decades; however, fibrin clots tend to produce an abundance of scar tissue, which is known to inhibit soft-tissue regeneration. Mesenchymal stem cells (MSCs) embedded in fibrin clots before repair could reduce scar tissue deposition and facilitate soft-tissue regeneration. To our knowledge, no published studies have directly evaluated the viability or bioactivity of MSCs in fresh human fibrin clots over time. The purpose of this study was to evaluate the viability and bioactivity of human MSCs inside human fibrin clots over time in nutritive and non-nutritive culture media., Questions/purposes: We hypothesized that human MSCs would (1) be captured inside fibrin clots and retain their proliferative capacity, (2) remain viable for at least 7 days in the fibrin clots, (3) maintain their proliferative capacity for at least 7 days in the fibrin clots without evidence of active apoptosis, and (4) display similar viability and proliferative capacity when cultured in a non-nutritive medium over the same time periods., Methods: Twelve patients (mean age 33.7 years; range 4-72 years) who underwent elective knee surgery were approached between February 2016 and October 2017; all patients agreed to participate and were enrolled. MSCs isolated from human skeletal muscle and banked after prior studies were used for this analysis. On the day of surgery and after expansion of the MSC population, 3-mL aliquots of phosphate-buffered saline containing approximately 600,000 labeled with anti-green fluorescent protein (GFP) antibodies were transported to the operating room, mixed in 30 mL of venous blood from each enrolled patient, and stirred at 95 rpm for 10 minutes to create MSC-embedded fibrin clots. The fibrin clots were transported to the laboratory with their residual blood for analysis. Eleven samples were analyzed after exclusion of one sample because of a processing error. MSC capture was qualitatively demonstrated by enzymatically digesting half of each clot specimen, thus releasing GFP-positive MSCs into culture. The released MSCs were allowed to culture for 7 days. Manual counting of GFP-positive MSCs was performed at 2, 3, 4, and 7 days using an inverted microscope at 100 x magnification to document the change in the number of GFP-positive MSCs over time. The intact remaining half of each clot specimen was immediately placed in proliferation media and allowed to culture for 7 days. On Days 1, 2, 3, 4, and 7, a small portion of the clot was excised, flash-frozen, cryosectioned (8-μm thickness), and immunostained with antibodies specific to GFP, Ki67 (indicative of active proliferation), and cleaved caspase-3 ([CC3]; indicative of active apoptosis). Using an inverted microscope, we obtained MSC cell counts manually at time zero and after 1, 2, 3, 4, and 7 days of culture. Intact fresh clot specimens were immediately divided in half; one half was placed in nutritive (proliferation media) and the other was placed in non-nutritive (saline) media for 1, 2, 3, 4, and 7 days. At each timepoint, specimens were processed in an identical manner as described above, and a portion of each clot specimen was excised, immediately flash-frozen with liquid nitrogen, cryosectioned (8-μm thickness), and visualized at 200 x using an inverted microscope. The numbers of stain-positive MSCs per field of view, per culture condition, per timepoint, and per antibody stain type were counted manually for a quantitative analysis. Raw data were statistically compared using t-tests, and time-based correlations were assessed using Pearson's correlation coefficients. Two-tailed p values of less than 0.05 (assuming unequal variance) were considered statistically significant., Results: Green fluorescence, indicative of viable GFP-positive MSCs, was absent in all residual blood samples after 48 hours of culturing; GFP-positive MSCs were visualized after enzymatic digestion of clot matrices. The number of GFP-positive MSCs per field of view increased between the 2-day and 7-day timepoints (mean 5.4 ± 1.5; 95% confidence interval, 4.7-6.1 versus mean 17.0 ± 13.6; 95% CI, 10.4-23.5, respectively; p = 0.029). Viable GFP-positive MSCs were present in each clot cryosection at each timepoint up to 7 days of culturing (mean 6.2 ± 4.3; 95% CI, 5.8-6.6). There were no differences in MSC counts between any of the timepoints. There was no visible evidence of GFP +/CC3 + double-positive MSCs. Combining all timepoints, there were 0.34 ± 0.70 (95% CI, 0.25-0.43) GFP+/Ki67+ double-positive MSCs per field of view. The mitotic indices at time zero and Day 7 were 7.5% ± 13.4% (95% CI, 3.0%-12.0%) and 7.2% ± 14.3% (95% CI, 3.3%-12,1%), respectively (p = 0.923). There was no visible evidence of GFP +/CC3 + double-positive MSCs (active apoptosis) at any timepoint. For active proliferation in saline-cultured fibrin clots, we found averages of 0.1 ± 0.3 (95% CI, 0.0-0.2) and 0.4 ± 0.9 (95% CI, 0.0-0.8) GFP/Ki67 double-positive MSCs at time zero and Day 7, respectively (p = 0.499). The mitotic indices in saline culture at time zero and Day 7 were 2.9% ± 8.4% (95% CI, 0.0%-5.8%) and 9.1% ± 20.7% (95% CI, 1.2%-17.0%; p = 0.144). There was no visible evidence of GFP +/CC3 + double-positive MSCs (active apoptosis) at any timepoint in either culturing condition., Conclusion: These preliminary in vitro results show that human MSCs mixed in unclotted fresh human venous blood were nearly completely captured in fibrin clots and that seeded MSCs were capable of maintaining their viability, proliferation capacity, and osteogenic differentiation capacity in the fibrin clot for up to 7 days, independent of external sources of nutrition., Clinical Relevance: Fresh human fibrin clots have been used clinically for more than 30 years to improve soft-tissue healing, albeit with scar tissue. Our results demonstrate that allogenic human MSCs, which reduce soft-tissue scarring, can be captured and remain active inside human fibrin clots, even in the absence a nutritive culture medium.