Faculty Bibliography

PURPOSE:To determine the incidence of ramp lesions and posteromedial tibial plateau (PMTP) bone bruising on magnetic resonance imaging (MRI) in patients with multiligament knee injuries (MLKIs) and an intact anterior cruciate ligament (ACL). METHODS:A retrospective review of consecutive patients surgically treated for MLKIs at 2 level I trauma centers between January 2001 and March 2021 was performed. Only MLKIs with an intact ACL that received MRI scans within 90 days of the injury were included. All MLKIs were diagnosed on MRI and confirmed with operative reports. Two musculoskeletal radiologists retrospectively rereviewed preoperative MRIs for evidence of medial meniscus ramp lesions (MMRLs) and PMTP bone bruises using previously established classification systems. Intraclass correlation coefficients were used to calculate the reliability between the radiologists. The incidence of MMRLs and PMTP bone bruises was quantified using descriptive statistics. RESULTS:A total of 221 MLKIs were identified, of which 32 (14.5%) had an intact ACL (87.5% male; mean age of 29.9 ± 8.6 years) and were included. The most common MLKI pattern was combined injury to the posterior cruciate ligament and posterolateral corner (n = 27, 84.4%). PMTP bone bruises were observed in 12 of 32 (37.5%) patients. Similarly, MMRLs were diagnosed in 12 of 32 (37.5%) patients. A total of 8 of 12 (66.7%) patients with MMRLs demonstrated evidence PMTP bone bruising. CONCLUSIONS:Over one-third of MLKI patients with an intact ACL were diagnosed with MMRLs on MRI in this series. PMTP bone bruising was observed in 66.7% of patients with MMRLs, suggesting that increased vigilance for identifying MMRLs at the time of ligament reconstruction should be practiced in patients with this bone bruising pattern. LEVEL OF EVIDENCE:Level IV, retrospective case series.

Background: Single-stage medial meniscus allograft transplantation (MAT) with concomitant anterior cruciate ligament reconstruction (ACLR) is a technically challenging procedure for management of knee pain and instability in younger patients, but clinical and functional outcomes data are sparse. The purpose of this study was to assess surgical and patient-reported outcomes following concomitant ACLR and medial MAT. Methods: We conducted a retrospective case series of patients who underwent medial MAT with concomitant primary or revision ACLR at our institution from 2010 to 2021 and had minimum 12-month follow-up. Complications, reoperations, visual analog scale (VAS) pain, satisfaction, Lysholm score, return to sport, and return to work outcomes were assessed. Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Interference, Pain Intensity, and Physical Function Scores were used to measure patients"™ functional status relative to the US population. P-values < 0.05 were considered significant. Results: The cohort consisted of 17 knees of 16 individual patients. The cohort was majority male (82.4%) with mean age of 31.9 years (range 19"“49 years) and mean body mass index (BMI) of 27.9 kg/m² (range 22.5"“53.3 kg/m²). Mean follow-up time was 56.8 months (range 13"“106 months). Most patients underwent revision ACLR (64.7%). The 1-year reoperation rate was high (23.5%), with two patients (11.8%) tearing their meniscus graft. Patient-reported outcomes indicated low VAS pain (mean 2.2), high satisfaction (mean 77.9%), and fair Lysholm score (mean 81.1). Return to work rate was high (92.9%), while return to sport rate was low (42.9%). Postoperative PROMIS scores were comparable or superior to the national average and correlated significantly with patient satisfaction (p < 0.05). Conclusions: The concomitant ACLR and MAT procedure is associated with excellent knee pain and functional outcomes and high rate of return to work after surgery, though the 1-year reoperation rate is high and rate of return to sport is low. Level of evidence: IV.

Introduction: While OCA has been shown to result in good long-term outcomes, there is still a considerable failure rate present with room for improvement. Objectives: The purpose of this study is to evaluate the impact that osteochondral allograft cartilage thickness has on contact pressures, and to simulate whether a mismatch of the subchondral bony interface relative to the host-recipient site results in altered biomechanics. Methods: Properties of articular cartilage and bone were incorporated into a finite element model to create a simulated osteochondral lesion (diameter: 10 mm, height: 10 mm, cartilage thickness: 2 mm, subchondral bone thickness: 8 mm). Five osteochondral plugs were constructed to fill the defect, with cartilage-to-bone ratios between 1:9 and 1:1. The plugs were inserted and given a static downward force of 5000 N. Resultant stresses and displacements were measured. Results: The 2:8 cartilage-to-bone ratio plug, matched with the recipient site, was deemed optimal based on its resultant stress and displacement. The 1:9 plug displaced less than the 2:8 match and endured greater stress per unit of cartilage volume, whereas the 3:7 plug also displayed similar displacement to the 1:9 plug but had greater cartilage volume and was able to distribute less stress per unit of cartilage volume. The 4:6 plug displaced to a similar extent as the 3:7 plug but displayed a unique pattern of strain. The 5:5 plug was considered nonfunctional, as the majority of displacement was seen in the cartilage of the recipient site rather than in the plug itself. Conclusions: The relationship between the cartilage-to-bone ratio in osteochondral allografts and that of their surroundings significantly impacts the distribution of stresses and predilection for micromotion at the repair site.

BACKGROUND:Magnetic resonance imaging (MRI) is an integral component of the treatment algorithm for proximal hamstring avulsion injuries. OBJECTIVE:The purpose of this study was to survey orthopedic surgeons and musculoskeletal radiologists on the reporting and analysis of proximal hamstring avulsions on MRI. METHODS:Two online surveys were developed to evaluate musculoskeletal radiologists' and orthopedic surgeons' perceptions of MRI-reporting for proximal hamstring avulsion injuries. Each survey was designed to provide information on physicians' best practices with respect to four primary questions (1) ischial tuberosity landmark determination (2) difficulties associated with measuring tendon retraction, (3) important ancillary findings, and (4) perceived clinical impact of measured retraction. Descriptive statistics were calculated for all categorical variables, which were reported as frequencies with percentages. Chi-squared test was utilized to compare rates of responses between surgeons and radiologists. Statistically significant differences were analyzed with post-hoc Fisher's exact tests; p < 0.05 considered statistically significant. RESULTS:218-Musculoskeletal radiologists and 33-orthopedic surgeons responded to their respective surveys. There were statistically significant differences with responses to two of the questions asked in both surveys; (1) in cases of complete hamstring avulsion (avulsion of both the semimembranosus and conjoint tendon), which arrow represents the tendon gap measurement used for planning surgery? p = 0.028; (2) in cases of avulsion of only the conjoint tendon, which arrow represents the tendon gap measurement used for planning surgery? p = 0.013. Post-hoc testing demonstrated that for either partial or complete hamstring avulsions, more surgeons use the conjoint tendon origin to measure tendon retraction than radiologists (p < 0.05 for both). Significantly more radiologists use the semimembranosus origin to measure hamstring retraction for partial or complete hamstring tears (p < 0.05 for both). However, for each of these questions, both radiologists and surgeons most frequently stated that the conjoint tendon landmark should be used for surgical planning. CONCLUSION/CONCLUSIONS:Musculoskeletal radiologists and orthopedists frequently utilize the conjoint tendon origin as an anatomic landmark for measuring complete and partial proximal hamstring avulsion injuries; though, orthopedists are more likely to utilize this landmark. Additionally, the broad surface area of the ischial tuberosity may lead to variability in measurement. CLINICAL IMPACT/CONCLUSIONS:Standard landmarks at the ischial tuberosity and/or detailed descriptions of tendon retractions would improve communication between radiologists and surgeons for proximal hamstring avulsions.

PURPOSE/OBJECTIVE:Multi-ligamentous knee injuries (MLKIs) are high-energy injuries that may infrequently present with concomitant patellar tendon rupture. There is limited information in the literature regarding these rare presentations, with even less information regarding clinical outcomes. Using propensity-score matching, the purpose of this study was to compare the outcomes of MLKIs with and without patellar tendon ruptures and to investigate the overall predictors of these outcomes. METHODS:Twelve patients who underwent surgical repair for combined MLKI and patellar tendon rupture from 2011 to 2020 with minimum 1-year follow-up data were identified from two separate institutions. Patients were propensity-score matched with a 1:1 ratio with controls based on age, body mass index (BMI), gender, and time from surgery. Patient-reported outcomes included International Knee Documentation Committee (IKDC) Subjective Knee Form, Lysholm and Tegner scores. RESULTS:Twelve MLKIs with concomitant patellar tendon injuries were identified out of a multicenter cohort of 237 (5%) patients sustaining MLKI and were case matched 1:1 with 12 MLKIs without extensor mechanism injuries. The average follow-up was 5.5 ± 2.6 years. There were no differences in Schenck Classification injury patterns. There were significant differences found across IKDC (Patellar Tendon mean: 53.1 ± 24.3, MLKI mean 79.3 ± 19.6, P < 0.001) and Lysholm scores (Patellar Tendon mean: 63.6 ± 22.3, MLKI mean 86.3 ± 10.7, P < 0.001) between the two, illustrating poorer outcomes for patients with concomitant patellar tendon ruptures. CONCLUSION/CONCLUSIONS:In the setting of MLKI, patients who have a concomitant patellar tendon rupture have worse functional outcomes compared to those without. This information will be important for patient counseling and might be considered to be added to Schenck classification, reflecting its prognostic value. LEVEL OF EVIDENCE/METHODS:Level IV.

BACKGROUND:Recent interest has surged in the anterolateral ligament (ALL) and complex (ALC) of the knee. Its existence and role in rotary stability of the knee, particularly in the setting of anterior cruciate ligament (ACL) reconstruction, remains a contentious and controversial topic. UNDERSTANDING THE ALC/UNASSIGNED:We must review our history and recognize the pioneers who pushed our understanding of the ALL forward before it was popularly recognized as a discrete structure. Additionally, given that many eponyms remain in common use related to the ALC, we must standardize our nomenclature to prevent misuse or misunderstanding of terms in the literature. In this review, modern understanding of the anterolateral ligament complex (ALC) is traced to 1829 by exploring eponymous terms first in anatomy and then in surgical technique. Understanding our history and terminology will allow us to better understand the ALC itself. CONCLUSION/CONCLUSIONS:This review aims to provide historical context, define terminology, and provide insight into the clinical relevance of the ALC.

BACKGROUND:Tibial tubercle anteromedialization (AMZ) is a commonly performed procedure for patients with patellofemoral instability or patellofemoral osteochondral disease. While prior studies have demonstrated that this form of osteotomy produces generally good outcomes, the time needed for return to work and return to sport remains unclear. This study aimed to determine the mean length of time before return to work and the rate of return to sport following AMZ. PATIENTS AND METHODS/METHODS:Patients who had undergone AMZ for either patellofemoral instability or isolated osteochon- dral defect with a minimum follow-up time of 1 year were identified. Patients less than 18 years of age were excluded. Patients were asked to complete a series of patient reported outcomes surveys including specific queries regarding their return to work and return to athletic activity. RESULTS:A total of 109 patients were included in this study. The majority were female (79 patients, 72.3%). The mean age was 30.74 ± 9.90 years at the time of surgery. The mean follow-up duration was 3.40 ± 1.97 years. Of the 109 patients, 104 (95.4%) had returned to work at the time of follow-up. Mean time to return to work was 2.96 ± 3.33 months (range: 0.25 to 24 months). Of the 90 patients who were involved in a sport or physical activity prior to injury, 64 patients (71.1%) had returned to sport at some level at the time of most recent follow-up. Of those who had returned to sport, mean time to return to sport was 9.21 ± 5.46 months (range: 1 to 24 months). CONCLUSIONS:At a minimum follow-up time of 1 year, patients who underwent AMZ were found to have a return to sport rate of 71% with a mean time of 9.21 months to return to athletic activity. Over 95% of AMZ patients had returned to work by 1 year after the procedure. Patients required an average of 3 months to return to work, although those with physically demanding jobs required slightly more time. Data from the current study is useful in setting expectations for patients undergoing tibial tubercle anteromedialization for patellofemoral instability or patellofemoral osteochondral disease.