Nepple, Jeffrey J.

Abstract The understanding and treatment of prearthritic hip disease has evolved remarkably over the past 20 years. The principal investigator and the multicenter Academic Network of Conservational Hip Outcomes Research (ANCHOR) group have had a key role in improving the quality of care for these patients suffering from the three most common prearthritic conditions: femoroacetabular impingement, developmental dysplasia of the hip, and residual Legg‐Calve‐Perthes Disease. We aim to demonstrate that based on the six quality of care dimensions as defined by Donabedian, our 20‐year academic journey has markedly improved the quality of care for young patients with prearthritic hip disease.

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.

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: Osteochondritis dissecans (OCD) occurs most commonly in the knees of young individuals. This condition is known to cause pain and discomfort in the knee and can lead to disability and early knee osteoarthritis. The cause is not well understood, and treatment plans are not well delineated. The Research in Osteochondritis Dissecans of the Knee (ROCK) group established a multicenter, prospective cohort to better understand this disease. Purpose: To provide a baseline report of the ROCK multicenter prospective cohort and present a descriptive analysis of baseline data for patient characteristics, lesion characteristics, and clinical findings of the first 1000 cases enrolled into the prospective cohort. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Patients were recruited from centers throughout the United States. Baseline data were obtained for patient characteristics, sports participation, patient-reported measures of functional capabilities and limitations, physical examination, diagnostic imaging results, and initial treatment plan. Descriptive statistics were completed for all outcomes of interest. Results: As of November 2020, a total of 27 orthopaedic surgeons from 17 institutions had enrolled 1004 knees with OCD, representing 903 patients (68.9% males; median age, 13.1 years; range, 6.3-25.4 years), into the prospective cohort. Lesions were located on the medial femoral condyle (66.2%), lateral femoral condyle (18.1%), trochlea (9.5%), patella (6.0%), and tibial plateau (0.2%). Most cases involved multisport athletes (68.1%), with the most common primary sport being basketball for males (27.3% of cases) and soccer for females (27.6% of cases). The median Pediatric International Knee Documentation Committee (Pedi-IKCD) score was 59.9 (IQR, 45.6-73.9), and the median Pediatric Functional Activity Brief Scale (Pedi-FABS) score was 21.0 (IQR, 5.0-28.0). Initial treatments were surgical intervention (55.4%) and activity restriction (44.0%). When surgery was performed, surgeons deemed the lesion to be stable at intraoperative assessment in 48.1% of cases. Conclusion: The multicenter ROCK group has been able to enroll the largest knee OCD cohort to date. This information is being used to further understand the pathology of OCD, including its cause, associated comorbidities, and initial presentation and symptoms. The cohort having been established is now being followed longitudinally to better define and elucidate the best treatment algorithms based on these presenting signs and symptoms.

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: Previous studies on periacetabular osteotomy (PAO) reported complication and reoperation rates of 5.9% and 10%, respectively. Hip arthroscopy is increasingly utilized as an adjunct procedure to PAO to precisely treat associated intra-articular pathology. The addition of this procedure has the potential of further increasing complication rates. Purpose: To determine the rates of complication and reoperation of combined hip arthroscopy and PAO for the treatment of acetabular deformities and associated intra-articular lesions. Study Design: Case series; Level of evidence, 4. Methods: Using a prospective database, the authors retrospectively reviewed 248 hips (240 patients) that underwent combined hip arthroscopy and PAO between 2007 and 2016. Data were collected at scheduled follow-up visits at approximately 1 month, 3 to 4 months, and 1 and 2 years after surgery. Mean follow-up from surgery was 3 years (range, 1-8 years). A total of 220 PAOs were done for symptomatic acetabular dysplasia, 18 for symptomatic acetabular retroversion, and 10 for combined acetabular dysplasia and acetabular retroversion. Central compartment arthroscopy was performed for treatment of intra-articular chondrolabral pathology in all cases. Select cases underwent femoral head-neck junction osteochondroplasty either arthroscopically before the PAO or through an open approach after it. Complications were graded according to the modified Dindo-Clavien complication scheme, which was validated for hip preservation procedures. Reoperations (excluding hardware removal) were recorded. Results: Grade III complications occurred among 7 patients (3%) while there were no grade IV complications. Grade III complications included deep infection (n = 3), wound dehiscence (n = 1), hematoma requiring exploration (n = 1), symptomatic heterotopic ossification requiring excision (n = 1), and deep venous thrombosis (n = 1). There were 13 reoperations (5%), and 3 were repeat hip arthroscopy. Univariate Cox hazard models were used to estimate the relative risk factors for complication and reoperation. Increased age (per decade) showed over twice the increased likelihood for complications (hazard ratio, 2.5; 95% CI, 1.67-3.74). Also, preoperative diagnosis of acetabular retroversion, not acetabular dysplasia, showed >3 times the increased risk of reoperation (hazard ratio, 3.05; 95% CI, 1.41-6.61). Conclusion: The rate of complications reported is comparable (3%) with previously published complication rates of PAO without hip arthroscopy. In this cohort, increasing age and diagnosis of acetabular retroversion were associated with higher complication and reoperation rates.

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.