Larson, Christopher Michael

Abstract Introduction: Femoroacetabular impingement commonly causes labral and cartilage damage. Understanding what clinical and CT-morphological factors are associated with increased labral and acetabular cartilage damage may give insight into the FAI pathophysiology. The present study aims to identify factors associated with labral and cartilage damage. Method: This is a prospective, multicenter cohort of patients undergoing primary arthroscopy for treatment of symptomatic FAI. Enrollment was between 2020 and 2022. The current study investigated predictive factors of advanced labral damage (detachment or full-thickness tear length >4cm) and advanced acetabular cartilage damage (delamination or full-thickness defect ≥200mm2). Finally, we performed external validation for the previously reported RAPID score that predicts high-grade cartilage injury. Results: There were 647 patients in the cohort. For labral injuries, there were 384/647 (59.4%) detachments and 154/647 (23.8%) full-thickness defects, with labral tears ≥4cm was present in 100/558 (17.9%) hips. Older age (OR:1.04, p=0.002), males (OR:1.83,p=0.005), and larger alpha angles at 2:00 (OR:1.02,p=0.04) were associated with full-thickness labral injuries. Older age (OR:1.06,p<0.001) and larger alpha angles at 2:00 (OR:1.03,p=0.01) were associated with tears ≥4cm. 258/679 (38.0%) patients had delamination or full-thickness cartilage defects. Older age (OR:1.09,p<0.001), males (OR:1.91 p=0.003), decreased IRF (OR:0.95,p<0.001), higher femoral version (OR:1.02,p=0.04), and larger alpha angles at 1:30 (OR:1.06,p<0.001) were associated with delamination or defect cartilage injuries. Advanced acetabular cartilage damage ≥200mm2 was present in 109/679 (16.8%) hips and was associated with larger alpha angles at 2:00 (OR:1.07,p<0.001), decreased IRF (OR:0.95,p<0.001), and males (OR:2.52,p=0.002), and age (OR:1.05,p=0.002). For RAPID score external validation, we used our data for their model (sex, Tonnis OA Grade, radiographic alpha angle) and found an AUC of 0.685. With an adjusted model using CT alpha angles, AUC improved to 0.703. Our final model improved the AUC to 0.809 and included age, sex, IRF, femoral version, and CT alpha angles. Conclusion: FAI commonly has associated labral and cartilage injuries. The current study found multiple predictive factors for advanced labral and cartilage injuries as well as for larger lesions. A model including age, sex, IRF, femoral version, and CT alpha angles appears to best predict acetabular cartilage damage. Further research should investigate how these affect outcomes.

Objectives: The purpose of this paper was to compare patient reported outcomes (PROMs) between isolated anterior cruciate ligament (ACLR) and ACLR with concomitant medial meniscus ramp and lateral meniscus root repairs and compare PROMs between different medial meniscus ramp and lateral meniscus root repair techniques. Methods: All patients with isolated (ISO) ACL reconstruction or ACL reconstruction with concomitant medial meniscus ramp and lateral meniscus root repairs with a minimum 2 years of follow-up were retrospectively evaluated. Institutional review board approval was obtained for this study. A final total of 42 ISO-ACL patients were matched based upon age, sex, and body mass index to 40 in the “terrible triad” (TT) cohorts. Outcome measures were obtained from 32 patients in the ISO cohort, and 38 patients in the TT cohort. The PROMs used for this study include the International Knee Documentation Committee (IKDC) Subjective Knee, Cincinnati, Tegner, Lysholm, Veterans RAND 12-Item Health Survey (VR-12), and Knee Injury and Osteoarthritis Outcomes Score (KOOS) questionnaire forms. T tests and chi-square goodness of fit tests were used to compare the above PROMs both pre- and postoperatively within each cohort, and between cohorts and rates of revision or reoperation. Results: The preoperative and postoperative PROMs between patients in the isolated cohort and the triad cohort demonstrated no significant differences, except for the Physical category of the VR-12, in which the triad cohort had significantly higher results (p = 0.04) (Figure 1). Both the isolated cohort and the triad cohort reported significant differences between pre- and postoperative PROMs within their own cohorts. When comparing methods of surgery, including all-inside vs. inside-out for the medial meniscus repairs and tunnel versus no-tunnel for the lateral meniscus root repairs, no significant differences were found between postoperative PROMs. Additionally, no significant difference was found in revision or reoperative rates between the triad and isolated cohorts (p = 0.374) (Figure 2), the all-inside versus inside-out medial meniscus cohorts (p = 0.267), or the tunnel vs. no-tunnel lateral meniscus cohorts (p = 0.781). Conclusions: There was no significant difference in PROMs between isolated ACLR versus ACLR with concomitant medial meniscus ramp and lateral meniscus root repairs. While the complexity of the TT ACLR patients was more involved, PROMs and healing rates were similar and performing concurrent medial ramp and lateral root repairs at the time of ACLR should be considered.

Objectives: Femoroacetabular impingement (FAI) is classically described as restricted internal rotation in flexion resulting in labral and cartilage pathology. Despite 20 years of FAI research, there is still limited understanding of the drivers of symptomatology in the subset of patients with underlying FAI morphology. While the prevalence of FAI morphologies is substantially higher in men, numerous studies have shown more women being treated for FAI compared to men. Soft-tissue laxity and hip instability are increasingly recognized as a potential contributor to symptoms in addition to FAI. The Beighton score is a well-accepted means to quantify soft-tissue laxity and has been validated for self-scoring. The purpose of the current study was to (1) investigate the prevalence of soft-tissue laxity in male and female patients presenting with symptomatic FAI in a multicenter prospective cohort study, and (2) correlate soft-tissue laxity with patient primary complaints of either mobility, stability, or pain. Methods: A prospective multicenter cohort study of 696 FAI patients undergoing primary hip arthroscopy surgery was performed and utilized for the current study. Inclusion criteria are patients aged 14 to 45 years old with idiopathic FAI not caused by childhood disease. Exclusion criteria are previous ipsilateral hip procedures or disease processes such as neuromuscular disease or Tonnis 2 or greater osteoarthritis. The Beighton score was assessed by electronic patient self-scoring. Beighton scores >4 were considered a marker of soft-tissue laxity. The MSP index was utilized to have patients rank from most to least the biggest problems with their hip: Mobility (M), Stability (S), or Pain (P). The chi-square or Fisher exact test were utilized to compare groups. Results: The prevalence of Beighton scores >4 was 57.2% in female patients, compared to 29.3% in male patients (p < 0.001). In female patients, 44.4%, 22.6%, and 7.7% had Beighton scores of 5+, 7+, and 9 respectively, compared to 16.7%, 5.8%, and 1.8% in male patients (all p < 0.005). In the overall FAI cohort, pain was the primary complaint in 72.1% of patients, compared to 24.2% complaining primarily of mobility and 3.7% complaining primarily of stability. Among female patients, the presence of soft-tissue laxity (relative to thresholds of Beighton 4, 5, 7, and 9) did not significantly influence the patient primary complaints (with pain being the predominant complaint). Overall, 85 female patients had a Beighton score of 7 or greater and only 2.4% reported stability of the hip as a primary complaint, compared to 2.4% of female patients with a Beighton <7. Stability was more commonly indicated as a second most important factor in the setting of soft-tissue laxity, compared to mobility. Among female patients with a Beighton >7, 29.5% reported stability as a primary or secondary complaint, compared to 15.2% of female patients with a Beighton score <7. Conclusions: Over half of female patients undergoing FAI surgery have underlying soft-tissue laxity as measured by the Beighton score. In the setting of soft-tissue laxity, patient primary symptomatic complaint remains pain, but a secondary complaint is significant more likely to be stability rather than mobility (compared to FAI patients without soft tissue laxity complain of mobility secondarily over stability). Further research is needed to better understand the role of soft-tissue laxity in the pathophysiology of FAI and the outcomes of surgical treatment.

Objectives: The purpose of this study was to radiographically assess changes in 1) patellar height, 2) anterior tibial translation (ATT), and 3) posterior tibial slope following supratubercle ACW-PTO and to compare changes in patellar height to a cohort of medial opening proximal tibial osteotomies (MOW-PTO). Methods: Patients who underwent supratubercle ACW-PTO by a single surgeon from July 2019-February 2023 were included. Institutional Review Board approval was obtained for this study. Radiographic assessment at four time points (preoperative, postoperative day 1, 3 months and 6 months) of patellar height (via the Caton Dechamps and Insall Salvati ratios), posterior tibial slope, and anterior tibial translation of the lateral tibial plateau relative to the lateral femoral condyle was completed. A comparison cohort of patients undergoing MOW-PTO was included for comparison of patellar height. Results: Patellar height averages ( n=16) after ACW-PTO using the Caton-Deschamps ratio (Figure 1) demonstrated a significant increase in patellar height on postoperative day 1 ( p=0.004), but were not significantly different at 3 and 6 months postoperatively (Table 2). Conversely, averages of patellar height after MOW-PTO ( n=28) demonstrated no difference on postoperative day 1, but then was significantly decreased by 6 months postoperatively ( p=0.005) (Table 1). There was a significant difference between the closing and opening-wedge cohorts when comparing the difference in patellar height using the CD ratio between preoperative and 6 months ( p=0.011). Anterior tibial translation in the ACW-PTO cohort was significantly decreased by an average of 9.0 mm from preoperative to postoperative values ( p<<0.001) (Figure 2). Posterior tibial slope in the ACW-PTO cohort was significantly decreased by an average of 11.8° from preoperative to postoperative values ( p<<0.001). Conclusions: Supratubercle ACW-PTO performed for ACL failure in the setting of increased tibial slope did not induce significant changes in patellar height postoperatively. Furthermore, following ACW-PTO there was a significant decrease in anterior tibial translation and posterior tibial slope.

Background: Full-thickness acetabular cartilage lesions are common findings during primary surgical treatment of femoroacetabular impingement (FAI). Purpose: To evaluate clinical outcomes after acetabular microfracture performed during FAI surgery in a prospective, multicenter cohort. Study Design: Cohort Study; Level of evidence, 3. Methods: Patients with FAI who had failed nonoperative management were prospectively enrolled in a multicenter cohort. Preoperative and postoperative (mean follow-up, 4.3 years) patient-reported outcome measures were obtained with a follow-up rate of 81.6% (621/761 hips), including 54 patients who underwent acetabular microfracture. Patient characteristics, radiographic parameters, intraoperative disease severity, and operative procedures were analyzed. Propensity matching using linear regression was used to match 54 hips with microfracture to 162 control hips (1:3) to control for confounding variables. Subanalyses of hips ≤35 and >35 years of age with propensity matching were also performed. Results: Patients who underwent acetabular microfracture were more likely to be male (81.8% vs 40.9%; P < .001), be older in age (35.0 vs 29.9 years; P = .001), have a higher body mass index (27.2 vs 25.0; P = .001), and have a greater alpha angle (69.6° vs 62.3°; P < .001) compared with the nonmicrofracture cohort (n = 533). After propensity matching to control for covariates, patients treated with microfracture displayed no differences in the modified Harris Hip Score or Hip Disability and Osteoarthritis Outcome Score ( P = .22-.95) but were more likely to undergo total hip arthroplasty (THA) (13% [7/54] compared with 4% [6/162] in the control group; P = .002), and age >35 years was associated with conversion to THA after microfracture. Microfracture performed at or before 35 years of age portended good outcomes with no significant risk of conversion to THA at the most recent follow-up. Conclusion: Microfracture of acetabular cartilage defects appears to be safe and associated with reliably improved short- to mid-term results in younger patients; modified expectations should be realized when full-thickness chondral lesions are identified in patients >35 years of age.

Background: Surgical treatment of femoroacetabular impingement (FAI) continues to evolve and is most commonly approached with either hip arthroscopy (HA) or surgical dislocation (SD) of the hip. The purpose of this study was to compare the outcomes of similar patients undergoing surgical treatment of FAI with either HA or SD. Methods: A prospective multicenter cohort study of patients undergoing primary surgical treatment of FAI was performed. Follow-up at a minimum of 1 year (mean, 4.3 years) was available for 621 hips (81.7%), including 399 procedures with HA and 222 procedures with SD. Propensity scores were calculated and reflect the likelihood of surgical treatment with HA versus SD for a given set of covariates. Propensity scores allowed 1:1 matching to identify similar patients at baseline. After propensity matching, 128 matched pairs of patients who underwent HA and 128 matched pairs of those who underwent SD were included in the study. The primary outcome was the postoperative modified Harris hip score (mHHS); secondary outcomes included the Hip disability and Osteoarthritis Outcome Score (HOOS), the University of California Los Angeles (UCLA) activity score, and the Short Form-12 (SF-12) physical and mental subscores, as well as the rate of persistent symptoms, revision surgery, and total hip arthroplasty (THA). Results: After propensity matching, the 2 groups exhibited similar distributions of all of the covariates that were included in the model. Both groups demonstrated significant improvements in all patient-reported outcomes (PROs). The final mHHS was not significantly different between the 2 matched groups (81.3 for the HA group versus 80.2 for the SD group, p = 0.67). Likewise, the HOOS pain subscale was similar at the time of final follow-up (77.6 versus 80.5, respectively, p = 0.32). No difference between the HA group and the SD group was identified in the rate of THA (0% and 3.1%, respectively, p = 0.41) and revision surgery (7.8% and 10.9%, respectively, p = 0.35); overall rates of persistent symptoms were 21.9% for the HA group and 24.4% for the SD group (p = 0.55). Conclusions: In a propensity-matched analysis of patients who were treated with either approach, patients undergoing HA or SD demonstrated similar outcomes at a mean of 4 years postoperatively. Level of Evidence: Therapeutic Level II . See Instructions for Authors for a complete description of levels of evidence.

Background: Symptomatic femoroacetabular impingement (FAI) is associated with hip pain, functional limitations, and secondary osteoarthritis. There is limited information from large patient cohorts defining the specific population affected by FAI. Establishing a large cohort will facilitate the identification of “at-risk” patients and will provide a population for ongoing clinical research initiatives. The authors have therefore established a multicenter, prospective, longitudinal cohort of patients undergoing surgery for symptomatic FAI. Purpose: To report the clinical epidemiology, disease characteristics, and contemporary surgical treatment trends in North America for patients with symptomatic FAI. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Upon approval of the institutional review boards at 8 institutions, 12 surgeons enrolled consecutive patients undergoing surgical intervention for symptomatic FAI. Patient demographics, physical examination data, radiographic data, diagnoses, operative data, and standardized patient-reported outcome measures were collected. The first 1130 cases are summarized in this study. Results: A total of 1076 consecutive patients (1130 hips) were enrolled; 55% (n = 622) were female, and 45% (n = 508) were male, with an average age of 28.4 years and average body mass index (BMI) of 25.1. Demographics revealed that 88% of patients who were predominantly treated for FAI were white, 19% reported a family history of hip surgery, 47.6% of hips had a diagnosis of cam FAI, 44.5% had combined cam/pincer FAI, and 7.9% had pincer FAI. Preoperative clinical scores (pain, function, activity level, and overall health) indicated a major dysfunction related to the hip. Surgical interventions were arthroscopic surgery (50.4%), surgical dislocation (34.4%), reverse periacetabular osteotomy (9.4%), limited open osteochondroplasty with arthroscopic surgery (5.8%), and limited open by itself (1.5%). More than 90% of the hips were noted to have labral and articular cartilage abnormalities at surgery; femoral head-neck osteochondroplasty was performed in 91.6% of the surgical procedures, acetabular rim osteoplasty in 36.7%, labral repair in 47.8%, labral debridement in 16.3%, and acetabular chondroplasty in 40.1%. Conclusion: This multicenter, prospective, longitudinal cohort is one of the largest FAI cohorts to date. In this cohort, FAI occurred predominantly in young, white patients with a normal BMI, and there were more female than male patients. The disease pattern of cam FAI was most common. Contemporary treatment was predominantly arthroscopic followed by surgical hip dislocation.

Background: The results of surgical treatment for femoroacetabular impingement have been increasingly reported, and more advanced intra-articular disease has been identified as an important predictive factor of outcome. Yet, the reliability of arthroscopic hip disease classification has not been well defined. Purpose/Hypothesis: To determine the intraobserver and interobserver reliability of the Beck classification of labral and articular cartilage disease (anterior-superior acetabular rim) encountered in hip arthroscopy. Secondly, we identified the sources of poor reliability that may be improved with future disease classification schemes. Our hypothesis was that the Beck classification of labral and chondral lesions would demonstrate substantial reliability, while the differentiation of early forms of disease would be a common source of disagreement. Study Design: Cohort study; Level of evidence, 3. Methods: Four experienced hip arthroscopists reviewed standardized arthroscopic videos of 40 cases. Arthroscopic findings at the anterior-superior acetabular rim were classified using the Beck classification of labral and articular cartilage disease. Repeat classification of videos was performed at least 2 weeks later. The reliability of arthroscopic classification was defined using the average weighted Cohen κ values and agreement rates. Results: Arthroscopic classification of labral disease using the Beck classification demonstrated moderate to substantial interobserver reliability (average κ = .62; range, .48-.78) and an overall agreement rate of 81.7%. Intraobserver reliability showed a similar level of reliability (average κ = .65; agreement rate, 80.6%). The differentiation between labral degeneration and labral detachment was a common source of disagreement. Similarly, the Beck classification of articular cartilage disease had moderate to substantial interobserver reliability (average κ = .65; range, .49-.78) and overall agreement rate of 57.5%. Intraobserver reliability showed a slightly better level of reliability (average κ = .80; agreement rate, 77.5%). The differentiation between articular cartilage malacia and debonding was a common source of disagreement. Conclusion: The arthroscopic classification of acetabular rim disease with the Beck classification has substantial interobserver reliability. This level of reliability is similar to previously reported arthroscopic disease classifications in the knee and shoulder and seems appropriate for future outcome reporting. Future classifications that eliminate common sources of disagreement may further improve the reliability.