Faculty Bibliography

OBJECTIVES/OBJECTIVE:Nordic ski athletes are at increased risk of developing hip pain and dysfunction secondary to femoroacetabular impingement syndrome (FAIS), but it is unclear whether hip symptomatology differs between ski jumping (SJ) and Nordic combined (NC) athletes. The purpose of this study was to compare patient-reported hip pain and dysfunction between elite Nordic ski athletes participating in SJ versus NC. METHODS:A cross-sectional study was conducted involving SJ and NC athletes who competed at the international and U.S. national level during the 2021-2022 season. Subjects were excluded if they had hip surgery within two years prior to enrollment. Subjects were asked to undergo diagnostic workup for FAIS including physical examination and plain radiographic imaging. Subjects were asked to complete a survey that collected information on athletic and training history and to complete the Hip Disability and Osteoarthritis Outcome Score (HOOS). Demographics, athletic/training history, and HOOS sub-scores were compared between the SJ and NC groups using Student's t-test, Wilcoxon rank-sum test, or Fisher's exact test, as appropriate. P-values <0.05 were considered significant. RESULTS:Twenty-four athletes (13 SJ, 11 NC) were included in the study. There were no statistically significant differences in age, sex, BMI, or age of menarche between the two groups (all p>0.05). There were also no statistically significant differences in the number of prior sports participated in, total hours of participation in prior sports, or total hours of training in Nordic specialization (all p>0.05). Among the 18 athletes who underwent physical examination (9 SJ, 9 NC), there were no statistically significant inter-group differences in hip range of motion or incidence of positive impingement tests (all p>0.05). Among the 19 athletes who underwent imaging (9 SJ, 10 NC), there were no statistically significant inter-group differences in the incidence of cam or pincer morphology in at least one hip (all p>0.05). SJ athletes had statistically significantly worse HOOS sub-scores for hip symptoms and stiffness, hip function in sports/recreational activities, and hip-related quality of life compared to NC athletes (all p<0.05). CONCLUSION/CONCLUSIONS:Elite SJ athletes have worse self-reported hip function compared to elite NC athletes despite comparable demographics, athletic history, and duration of ski training. LEVEL OF EVIDENCE/METHODS:IV.

BACKGROUND:Force plate-based jump testing may serve as a potential alternative to traditional return to sport (RTS) testing batteries. The purpose of our study was to identify force plate jump metrics that were predictive of RTS test findings in patients who were at least six months postoperative following anterior cruciate ligament reconstruction (ACLR). METHODS:We conducted a cross-sectional study of patients who underwent ACLR at our center and were at least six months postoperative. Subjects completed a multimodal Institutional RTS (IRTS) testing battery which included range of motion (ROM) testing and isokinetic quadriceps strength testing. Subjects also completed a countermovement jump testing protocol on a commercially-available force plate. Jump metrics predictive of IRTS test findings were identified using multivariable linear and logistic regression with stepwise selection. Model significance was assessed at α=0.002. RESULTS:Sixteen patients (7M, 9F) were enrolled in our study with median age of 29 years (range 20-47). Relative concentric impulse was positively predictive of knee flexion active ROM (β=7.07, P=0.01) and passive ROM (β=9.79, P=0.003). Maximum power was positively predictive of quadriceps strength at 60 deg/s (β=3.27, P<0.001) and 180 deg/s (β=2.46, P<0.001). Center-of-pressure (COP) shift acceleration along the force plate X-axis was negatively predictive of Bunkie lateral test score (β=-945, P<0.001) and medial test score (β=-839, P=0.03). CONCLUSIONS:Force plate-derived vertical jump testing metrics are predictive of certain components of a multimodal RTS physical assessment for ACLR patients, including knee flexion ROM, quadriceps strength on isokinetic testing, and Bunkie Test performance.

PURPOSE:To identify differences in the time taken to achieve the minimum clinically important difference (MCID), substantial clinical benefit (SCB), and patient-acceptable symptom state (PASS) following primary hip arthroscopy for the treatment of femoroacetabular impingement syndrome (FAIS) among patients of different body mass index (BMI) categories. METHODS:We conducted a retrospective comparative study of hip arthroscopy patients with minimum 2-year follow-up. BMI categories were defined as normal (18.5 ≤ BMI < 25.0), overweight (25.0 ≤ BMI <30.0), or class I obese (30.0≤BMI<35.0). All subjects completed the modified Harris Hip Score (mHHS) prior to surgery and at 6 months, 1 year, and 2 years postoperative. MCID and SCB cutoffs were defined as pre-to-postoperative increases in mHHS by ≥8.2 and ≥19.8, respectively. PASS cutoff was set at postoperative mHHS ≥74. Time to achievement of each milestone was compared using the interval-censored EMICM algorithm. The effect of BMI was adjusted for age and sex using an interval-censored proportional hazards model. RESULTS:285 patients were included in the analysis: 150 (52.6%) normal BMI, 99 (34.7%) overweight, and 36 (12.6%) obese. Obese patients had lower mHHS at baseline (P = .006) and at 2-year follow-up (P = .008). There were no significant intergroup differences in time to achievement for MCID (P = .92) or SCB (P = .69), but obese patients had longer time to PASS than normal BMI patients (P = .047). Multivariable analysis found obesity to be predictive of longer time to PASS (HR = .55; P = .007) but not MCID (HR = 0.91; P = .68) or SCB (HR = 1.06; P = .30). CONCLUSIONS:Class I obesity is associated with delays in achieving a literature-defined PASS threshold after primary hip arthroscopy for FAIS. LEVEL OF EVIDENCE:Level III, retrospective comparative study.

PURPOSE/OBJECTIVE:The aim of our study was to identify differences in the time taken to achieve the minimum clinically important difference (MCID), substantial clinical benefit (SCB), and patient-acceptable symptom state (PASS) following primary hip arthroscopy for the treatment of femoroacetabular impingement syndrome (FAIS) among patients of different body mass index (BMI) categories. METHODS:We conducted a retrospective comparative study of hip arthroscopy patients with minimum 2-year follow-up. BMI categories were defined as normal (18.5 ≤ BMI < 25.0), overweight (25.0 ≤ BMI <30.0), or class I obese (30.0≤BMI<35.0). All subjects completed the modified Harris Hip Score (mHHS) prior to surgery and at 6 months, 1 year, and 2 years postoperative. MCID and SCB cutoffs were defined as pre-to-postoperative increases in mHHS by ≥8.2 and ≥19.8, respectively. PASS cutoff was set at postoperative mHHS ≥74. Time to achievement of each milestone was compared using the interval-censored EMICM algorithm. The effect of BMI was adjusted for age and sex using an interval-censored proportional hazards model. RESULTS:285 patients were included in the analysis: 150 (52.6%) normal BMI, 99 (34.7%) overweight, and 36 (12.6%) obese. Obese patients had lower mHHS at baseline (P = .006) and at 2-year follow-up (P = .008). There were no significant intergroup differences in time to achievement for MCID (P = .92) or SCB (P = .69), but obese patients had longer time to PASS than normal BMI patients (P = .047). Multivariable analysis found obesity to be predictive of longer time to PASS (HR = .55; P = .007) but not MCID (HR = 0.91; P = .68) or SCB (HR = 1.06; P = .30). CONCLUSIONS:Class I obesity is associated with delays in achieving a literature-defined PASS threshold after primary hip arthroscopy for FAIS. However, future research should consider incorporating PASS anchor questions to determine whether obesity truly carries a risk of delayed achievement of a satisfactory state of health as it pertains to the hip. LEVEL OF EVIDENCE/METHODS:III, retrospective comparative study.

PURPOSE/UNASSIGNED:To evaluate functional outcomes and satisfaction in patients who underwent telerehabilitation (telerehab) compared with in-person rehabilitation after arthroscopic meniscectomy. METHODS/UNASSIGNED:A randomized-controlled trial was conducted including patients scheduled to undergo arthroscopic meniscectomy for meniscal injury by 1 of 5 fellowship-trained sports medicine surgeons between September 2020 and October 2021. Patients were randomized to receive telerehab, defined as exercises and stretches provided by trained physical therapists over a synchronous face-to-face video visit or in-person rehabilitation for their postoperative course. International Knee Documentation Committee Subjective Knee Form (IKDC) score and satisfaction metrics were collected at baseline and 3 months postoperatively. RESULTS/UNASSIGNED: = .044) if there were in the in-person group. Satisfaction differed significantly between the 2 groups at the end of their rehabilitation course, and only 64% of those in the telerehab group would elect to undergo telerehab again for future indications. Furthermore, they believed that future rehabilitation would benefit from a hybrid model. CONCLUSIONS/UNASSIGNED:Telerehab showed no difference versus traditional in-person rehabilitation in terms of functional outcomes up to 3 months after arthroscopic meniscectomy. However, patients were less satisfied with telerehab. LEVEL OF EVIDENCE/UNASSIGNED:I, randomized controlled trial.

With an increased appreciation of the importance an intact meniscus has on normal knee kinematics and function, more meniscal tears are being treated with a repair rather than partial meniscectomy. There are several techniques for repairing torn meniscal tissue, including the outside-in, inside-out, and all-inside repairs. Each technique comes with its advantages and drawbacks. The inside-out and outside-in techniques allow for greater control of the repair using knots outside the joint capsule; however, they pose a risk for neurovascular injury and require additional incisions. Arthroscopic all-inside repairs have seen increasing popularity, but with current techniques, fixation is achieved either with intra-articular knots or extra-articular implants, leading to variable outcomes and the potential for postoperative complications. This technical note describes the use of SuperBall, an all-inside meniscus repair device that provides an all-arthroscopic approach, no intraarticular knots or implants, and surgeon-guided tensioning of the meniscus repair.

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.

Femoroacetabular impingement (FAI) has emerged as a common cause of hip pain, especially in young patients. While the exact cause of FAI is unknown, it is thought to result from repetitive microtrauma to the proximal femoral epiphysis leading to abnormal biomechanics. Patients typically present with groin pain that is exacerbated by hip flexion and internal rotation. Diagnosis of FAI is made through careful consideration of patient presentation as well as physical exam and diagnostic imaging. Use of radiographs can help diagnose both cam and pincer lesions, while the use of MRI can diagnose labral tears and cartilage damage associated with FAI. Both non-operative and surgical options have their role in the treatment of FAI and its associated labral tears; however, hip arthroscopy has had successful outcomes when compared with physical therapy alone. Unfortunately, chondral lesions associated with FAI have had poorer outcomes with a higher conversion rate to arthroplasty. Capsular closure following hip arthroscopy has shown superior clinical outcomes and therefore should be performed if possible. More recently, primary labral reconstruction has emerged in the literature as a good option for irreparable labral tears. While non-operative management may have its role in treating patients with FAI, hip arthroscopy has developed a successful track record in being able to treat cam and pincer lesions, chondral damage, and labral injuries.

Isolated lateral compartment osteoarthritis of the knee is a rare condition affecting approximately 1% of the population, which is ten times less common than osteoarthritis affecting only the medial compartment. Unicompartmental knee arthroplasty (UKA) has many potential advantages over total knee arthroplasty. The benefits of UKA include a smaller incision, preservation of more native tissue (including cruciate ligaments and bone), decreased blood loss, and better overall proprioception. When UKA was first introduced in the 1970s, the outcomes of medial UKA (MUKA) were poor, but the few cases of lateral UKA (LUKA) showed promise. Since that time, there has been a relative paucity of literature focused specifically on LUKA given it is a rare procedure. Refinements in patient selection criteria, implant design, and surgical technique have been made leading to increased popularity. A review of the recent literature reveals that LUKA is associated with excellent long-term clinical outcomes and implant survivorship when performed in properly selected patients. Implant design options include fixed vs mobile bearing as well as metal backed vs all polyethylene tibial component, with improved outcomes noted with fixed bearing designs. Three reasons cited for revision (i.e., fracture of the femoral component, fracture of the tibial component, and valgus malalignment) had been reported in past literature but not recently. Presently, while rare, the most common cause of failure and need for revision are osteoarthritis progression and aseptic loosening. Despite the need for an occasional revision procedure, the survivorship of LUKA is comparable to MUKA, although it should be noted that outcomes of MUKA have been notably varied. Continued pursuit of improved techniques and implant designs will continue to show LUKA to be an excellent procedure for appropriately indicated patients.