Hip Outcome Score-Sports Subscale Research Articles

Repeat Revision Hip Arthroscopy Outcomes Match That of Initial Revision But Not That of Primary Surgery for Femoroacetabular Impingement Syndrome

To (1) report on pre- and postoperative patient-reported outcome (PRO) scores for patients undergoing repeat revision surgery in short-term follow-up and (2) compare minimal clinically important difference (MCID) and patient acceptable symptomatic state achievement between primary, revision, and repeat revision hip arthroscopy cohorts. Data from consecutive patients undergoing revision hip arthroscopy from January 2012 to February 2019 were retrospectively reviewed. Hips that underwent 2 revision hip arthroscopic surgeries were identified and matched 1:3 to patients undergoing revision surgery and 1:3 to patients undergoing primary surgery by age, sex, and body mass index. Baseline demographic data, surgical indications, and hip-specific PROs were collected were obtained preoperatively and at minimum 1-year follow-up. MCID was calculated individually for each cohort. Twenty patients who underwent repeat revision were matched to 60 patients who underwent revision and 60 primary patients. Patients who underwent repeat revision achieved MCID on all investigated PROs at a similar rate to patients undergoing primary surgery (90.0% vs 91.7%, P= .588) and at a greater rate than patients undergoing first-time revision surgery (90.0% vs 71.7%, P= .045). Patients who underwent repeat revision achieved patient acceptable symptomatic state on all investigated PROs at a similar rate to patients who underwent first-time revision (30.0% vs 55.0%, P= .053) but at a significantly lower rate than primary patients (30.0% vs 76.7%, P < .001). However, patients undergoing repeat revision surgery had significantly lower preoperative PROs (P < .001 for all) and no significant difference in PROs at minimum 1-year follow-up compared with patients undergoing revision (P > .05). Compared with the primary cohort, patients who underwent repeat revision had significantly lower Hip Outcome Score-Activities of Daily Living (77.3 ± 16.7 vs 86.1 ± 14.4; P= .034), Hip Outcome Score-Sports Subscale (60.6 ± 27.2 vs 76.1 ± 23.8; P < .001), and modified Harris Hip Score (69.2 ± 19.3 vs 81.7 ± 16.1; P= .048) at a minimum of 1-year follow-up. Second-time revision hip arthroscopy, which often requires advanced procedures, results in clinically significant improvement in PROs; however, outcomes for repeat revision cases are similar to first-time revision cases but inferior to those obtained following primary surgeries. Level III, retrospective case-control study.

Machine Learning Algorithms Predict Functional Improvement After Hip Arthroscopy for Femoroacetabular Impingement Syndrome in Athletes.

Despite previous reports of improvements for athletes following hip arthroscopy for femoroacetabular impingement syndrome (FAIS), many do not achieve clinically relevant outcomes. The purpose of this study was to develop machine learning algorithms capable of providing patient-specific predictions of which athletes will derive clinically relevant improvement in sports-specific function after undergoing hip arthroscopy for FAIS. A registry was queried for patients who had participated in a formal sports program or athletic activities before undergoing primary hip arthroscopy between January 2012 and February 2018. The primary outcome was achieving the minimal clinically important difference (MCID) in the Hip Outcome Score-Sports Subscale (HOS-SS) at a minimum of 2 years postoperatively. Recursive feature selection was used to identify the combination of variables, from an initial pool of 26 features, that optimized model performance. Six machine learning algorithms (stochastic gradient boosting, random forest, adaptive gradient boosting, neural network, support vector machine, and elastic-net penalized logistic regression [ENPLR]) were trained using 10-fold cross-validation 3 times and applied to an independent testing set of patients. Models were evaluated using discrimination, decision-curve analysis, calibration, and the Brier score. A total of 1,118 athletes were included, and 76.9% of them achieved the MCID for the HOS-SS. A combination of 6 variables optimized algorithm performance, and specific cutoffs were found to decrease the likelihood of achieving the MCID: preoperative HOS-SS score of ≥58.3, Tönnis grade of 1, alpha angle of ≥67.1°, body mass index (BMI) of >26.6 kg/m2, Tönnis angle of >9.7°, and age of >40 years. The ENPLR model demonstrated the best performance (c-statistic: 0.77, calibration intercept: 0.07, calibration slope: 1.22, and Brier score: 0.14). This model was transformed into an online application as an educational tool to demonstrate machine learning capabilities. The ENPLR machine learning algorithm demonstrated the best performance for predicting clinically relevant sports-specific improvement in athletes who underwent hip arthroscopy for FAIS. In our population, older athletes with more degenerative changes, high preoperative HOS-SS scores, abnormal acetabular inclination, and an alpha angle of ≥67.1° achieved the MCID less frequently. Following external validation, the online application of this model may allow enhanced shared decision-making.

Complete Capsular Closure Provides Higher Rates of Clinically Significant Outcome Improvement and Higher Survivorship Versus Partial Closure After Hip Arthroscopy at Minimum 5-Year Follow-Up

To (1) compare the rates of reaching threshold hip-specific outcome scores for achieving the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) in patients who underwent partial versus complete T-capsulotomy repair and (2) identify the failure rates in each group 5 years after undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS). Data from consecutive patients who underwent hip arthroscopy for FAIS performed by a single fellowship-trained surgeon from January 2011 to March 2013 were collected and analyzed. Baseline data, hip-specific outcomes, and clinical failure rates were recorded at a minimum of 5 years postoperatively. Patients with partial T-capsulotomy repair were matched 1:3 by age, body mass index, and sex to patients with complete T-capsulotomy repair. Threshold scores for achieving the MCID and PASS were calculated and compared between the 2 groups. Additionally, rates of revision and conversion to total hip arthroplasty (THA) were compared between the groups. A total of 379 patients were available for analysis (39 partial and 340 complete repairs), with 100 patients included in the matching process (25 in the partial-repair group and 75 in the complete-repair group). Comparison of radiographic parameters, including the Tönnis grade, alpha angle, and lateral center-edge angle, between the 2 groups showed no statistically significant difference (P > .05 for all). Comparison of postoperative score averages between the partial- and complete-closure groups showed a significant difference in the Hip Outcome Score-Activities of Daily Living Subscale (85.4 ± 17.7 vs 94.6 ± 7.8, P < .001), Hip Outcome Score-Sports Subscale (76.6 ± 26.2 vs 89.3 ± 16.8, P= .034), modified Harris Hip Score (83.2 ± 19.7 vs 90.5 ± 11.2, P= .035), and visual analog scale pain score (24.5 ± 30.8 vs 13.4 ± 15.8, P= .035). A total of 65 complete-repair patients (95.6%) achieved the MCID for at least 1 outcome measure versus 18 patients with partial repair (78.3%) (P= .04). A total of 69 complete-repair patients (92%) achieved the PASS for at least 1 outcome measure versus 18 partial-repair patients (72%) (P= .017). Of the 39 partial-repair patients, 35.9% (n= 14) underwent revision or conversion to THA, as compared with 2.9% (n= 10) in the overall cohort. At a minimum 5-year follow-up, patients with complete capsular closure after hip arthroscopy for FAIS show superior long-term outcomes and achieve higher rates of meaningful clinical success when compared with patients with partial capsular closure. Furthermore, patients with partial capsular repair undergo revision or conversion to THA at high rates. Level III, retrospective comparative study.

Multi-center Analysis of Sports-Related Outcomes of Adolescents following Hip Arthroscopy

Symptoms of hip pathology are becoming more commonly recognized in pediatric and adolescent athletes. Arthroscopic surgical approaches to correct morphological and structural abnormalities in adults have been introduced to younger patients to improve dysfunction and reduce the progression of hip pathology. However, a paucity in the literature exists regarding how the pediatric and adolescent athletes respond to hip preservation surgery and the impact hip arthroscopy may have on athletic activity. The purpose of this study was to describe the changes of functional and sports related outcomes of adolescents at 2 years following arthroscopic hip preservation surgery. De-identified patient data from a multi-centered hip arthroscopy registry from January 1, 2016 – January 1, 2017 was analyzed. The data was collected from 7 individual surgeon practices that each perform greater than 100 hip arthroscopy cases per year for a minimum of 8 years. A statistical software program (SPSS, IBM Inc.) computed paired t-tests with an a priori alpha set at 0.05 to determine significance of the change in scores from pre-operative to 2-years post hip arthroscopic surgery. Outcome measures included visual analog pain scales, Hip Outcome Score Sports subscale (HOS Sports), and International Hip Outcome Tool-12 scores. The magnitude to change in these outcome measures and the frequency of patients that surpassed Patient Acceptable Symptomatic State (PASS) scores was determined for the cohort. A chi square analysis was then conducted to determine changes in sports-related skills and activities from pre to post hip preservation surgery. There were 50 adolescent athletes (14 male; 36 female) included in the analysis. The most common sports were running (28%), lacrosse (6%), baseball (10%), swimming (10%), dance (8%), and cheerleading (8%). Sports related outcomes measured by the HOS Sports Subscale improved (p<0.001) from an average score of 43.7 (SD=21.3) to 90.0 (SD=10.0), with 54% meeting the PASS score. Running was the most commonly reported sport specific skill/activity that was categorized as extremely difficult or unable to do by 46% of athletes prior to surgery. This percentage dropped to 8% of athletes at 2 years post-surgery. The greatest improvements of sports specific activities were noted in jumping, landing, stop/start movements, and cutting/lateral movements in which 88% - 90% of the athletes reported either slight or no difficulty at all with these activities. Self-reported functional outcomes showed that the iHOT-12 improved (p<0.001) from an average score of 37.4 (SD 17.4) to 85.4 (SD=15.0), with 72% of patients meeting the PASS score. Pain visual analog scores also improved (p<0.001) from 39.7 (SD=21.7) to 12.4 (SD=15.8). The results of this study show that sport specific function of adolescent athletes greatly improves and is sustained 2 years following hip preservation surgery. Running was shown to be the most difficult sport specific skill to perform due to hip pathology prior to surgery, but improved after surgery. Other skills that showed large improvements after surgery included jumping, landing, stopping/starting, and cutting/lateral movements. Despite large improvements, some athletes may report sports related dysfunction at 2 years following hip preservation surgery.

Clinical and Radiographic Presentation of Capsular Iatrogenic Hip Instability After Previous Hip Arthroscopy

Background: The clinical and radiographic features of iatrogenic hip instability following hip arthroscopy have been described. However, the prevalence of presenting symptoms and associated imaging findings in patients with hip instability has not been reported. Purpose: To detail the prevalence of clinical and magnetic resonance arthrogram (MRA) findings in a cohort of patients with isolated hip instability and to determine midterm patient-reported outcomes in this patient population. Study Design: Case series; Level of evidence, 4. Methods: We retrospectively reviewed patients from 2014 to 2016 who underwent an isolated capsular repair in the revision hip arthroscopy setting. Patients were excluded if they underwent any concomitant procedures, such as labral repair, reconstruction, femoral osteoplasty, or any other related procedure. Several clinical data points were reviewed, including painful activities, mechanical symptoms, subjective instability, Beighton scores, axial distraction testing (pain, toggle, and apprehension), and distractibility under anesthesia. Patient-reported outcomes—including modified Harris Hip Score, Hip Outcome Score–Sports Subscale, Patient-Reported Outcome Measurement Information System (PROMIS) Physical Function Computer Adaptive Test, and a return patient hip questionnaire—were collected pre- and postoperatively. Pre-revision radiographs were obtained, and lateral center-edge angle and alpha angle were measured on anteroposterior and frog-leg lateral views, respectively. Pre-revision MRAs were reviewed and evaluated for capsular changes. Capsular changes were defined as follows: 0, normal; 1, capsular redundancy; 2, focal capsular rent; and 3, gross extravasation of fluid from the capsule. Results: A total of 31 patients met inclusion criteria (5 male, 26 female; 14 right and 17 left hips). The mean age of patients was 36 years (range, 20-58 years). Overall, 27 (87%) reported hip pain with activities of daily living, and 31 (100%) experienced pain with sports or exercise. In addition, 24 (77%) had at least 1 positive finding on axial distraction testing. All patients had evidence of capsular changes on review of pre-revision MRAs. Out of 31 patients, 23 (74%) were available for follow-up at a minimum of 3.3 years and a mean ± SD of 4.6 ± 0.8 years. On average, modified Harris Hip Score improved by 20.3, Hip Outcome Score–Sports Subscale by 25.1, and PROMIS Physical Function Computer Adaptive Test by 6.4. Additionally, 20 (87%) patients reported improved or much improved physical ability, and 18 (78%) reported improved or much improved pain. Conclusion: The current study suggests that patients with hip instability demonstrate high rates of pain with activities of daily living and exercise, positive findings on axial distraction testing, and evidence of capsular changes on magnetic resonance imaging. Furthermore, these patients improve with revision surgery for capsular repair at midterm follow-up.

Patients With a Hypotrophic Labrum Achieve Similar Outcomes After Primary Labral Repair Compared With Patients With a Normal-Sized Labrum: A Matched Cohort Analysis of 346 Patients With Femoroacetabular Impingement Syndrome

To compare patient functional scores and rates of achieving minimum clinically important differences (MCID) and patient acceptable symptomatic state (PASS) between patients with a hypotrophic labrum with those with a normal labrum width at a minimum 1-year follow-up from arthroscopic treatment of femoroacetabular impingement syndrome. Data from consecutive patients who underwent primary hip arthroscopy between November 2015 and July 2018 for the treatment of femoroacetabular impingement syndrome were analyzed. Baseline demographic data, preoperative patient-reported outcome measures (PROMs), and minimum 1-year PROMs, including Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sports Subscale, modified Harris Hip Score, international Hip Outcome Tool 12 questions, and visual analog scale for pain and satisfaction were recorded. The labrum size was determined using an arthroscopic probe at the 12- to 2-o'clock position with a hypotrophic labrum being defined as <4 mm and normal labrum defined as having a width between 4 and 7 mm on the articular side. Patients with hypotrophic labrum were matched 1:1 by age and body mass index to patients with normal labrum width. A total of 346 patients were included in the study with an average age of 31.4 ± 11.9 and a majority being female (72.0%). There were 173 in each of the normal and hypotrophic groups. There were no significant differences seen in 1-year PROMs between the 2 groups (P > .05 for all). The normal labrum group achieved MCID at a rate of 75% to 84% and PASS at a rate of 51% to 70%. The hypotrophic labrum group achieved MCID at a rate of 70% to 85% and PASS at a rate of 57% to 71%. There were no significant differences in rates between each group (P > .05 for all). Patients with an intraoperative finding of labral hypotrophy achieve 1-year meaningful clinical outcome at the same rate as those with normal labral width following arthroscopic labral repair. III, Case-control study.

Patients With Borderline Hip Dysplasia Achieve Clinically Significant Improvement After Arthroscopic Femoroacetabular Impingement Surgery: A Case-Control Study With a Minimum 5-Year Follow-up

Background: Hip arthroscopy for the treatment of femoroacetabular impingement syndrome (FAIS) in patients with borderline hip dysplasia (BHD) is becoming a more common practice. However, the literature on achieving meaningful outcomes at midterm follow-up, as well as predictors of these outcomes, is limited. Purpose: To (1) compare the rates of achieving meaningful clinical outcomes between patients with and without BHD and (2) identify the predictors for achieving clinical success among patients with BHD 5 years after undergoing hip arthroscopic surgery for FAIS. Study Design: Cohort study; Level of evidence, 3. Methods: Data from consecutive patients who underwent primary hip arthroscopic surgery with routine capsular closure for the treatment of FAIS between January 2012 and August 2014 were collected and retrospectively analyzed. Patients with BHD (lateral center-edge angle [LCEA] 20°-25°) were matched 1:2 by age (±1 year) and body mass index (BMI; ±5 kg/m2) to control patients with normal acetabular coverage (LCEA 25°-40°). Data collected included baseline and 5-year postoperative patient-reported outcomes. The minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) were calculated for each patient-reported outcome measure and compared between the 2 groups. A binary logistic regression analysis was used to identify significant predictors of achieving the MCID and PASS in the BHD group. Results: The MCID in the BHD group was defined as 9.6, 14.1, and 9.5 for the Hip Outcome Score–Activities of Daily Living, Hip Outcome Score–Sports Subscale, and modified Harris Hip Score, respectively. Threshold scores for achieving the PASS in both groups were 90.9, 76.6, and 81.9, respectively. A total of 88 patients were identified with having BHD and were matched to 176 controls. No statistical differences were identified for age, BMI, or sex. Both the BHD and the non-BHD groups had statistically significant increases in patient-reported outcome scores over the 5-year period, but the difference in both groups was not statistically significant (P > .05 for all). There was no statistical difference in the frequency of patients in the BHD and non-BHD groups achieving the MCID (86.6% vs 85.2%, respectively; P = .804) or PASS (76.0% vs 73.7%, respectively; P = .675) on at least 1 outcome measure. The logistic regression model demonstrated that being physically active (odds ratio [OR], 27.59; P = .005) and being female (OR, 14.64; P = .025) were independent predictors of achieving the MCID, while running (OR, 11.1; P = .002), being female (OR, 7.6; P = .011), and a larger preoperative LCEA (OR, 2.3; P = .001) were independent preoperative predictors of achieving the PASS. Conclusion: The rates of achieving clinical success 5 years after undergoing arthroscopic treatment with capsular closure for FAIS were not significantly different between patients with BHD and those with normal acetabular coverage. Being physically active, running for exercise, female sex, and a larger LCEA were preoperative predictors of achieving clinical success at 5 years in patients with BHD.

Outcomes Following the Urgent Surgical Management of Displaced Femoral Neck Stress Fractures.

To review the clinical course, complication rates, and mid-term functional outcomes associated with the treatment of displaced femoral neck stress fractures (FNSFs). Retrospective Case Series. Military Tertiary Referral Center. Twenty-one operatively treated displaced FNSFs between 2002 and 2015. Urgent reduction and fixation was performed. If nonunion developed, an intertrochanteric osteotomy was performed. Nonunion, osteonecrosis (ON) of the femoral head, conversion to arthroplasty, modified Harris Hip Score, pain score, and Hip Outcome Score (HOS). Two (9.1%) patients developed nonunion. Both united after revision with intertrochanteric osteotomy. ON developed in one patient (4.8%) who was converted to arthroplasty. Average pain score at final follow-up was 2.0 (range 0-5). Average Modified Harris Hip Score was 84 (range 54-100). Average HOS Activities of Daily Living subscale was 80.9 (range 45.6-100). Average HOS Sport subscale was 69.8 (range 27.8-100). Larger displacement on injury films correlated with lower Modified Harris Hip Scores (P = 0.048) and lower HOS Sports Subscale Single Assessment Numeric Evaluation (P = 0.023). The need for an open reduction trended toward being a risk factor for nonunion (P = 0.081). This study represents the largest series of patients undergoing urgent surgery for displaced FNSFs. Nonunion and ON is found at a similar rate to what is reported in the young traumatic literature. Pain and outcome scores compare favorably to other hip pathology in young adults. Initial injury severity is variably correlated to final outcome scores. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Preoperative Duration of Symptoms Is Associated With Outcomes 5 Years After Hip Arthroscopy for Femoroacetabular Impingement Syndrome

To determine the effect of the preoperative duration of femoroacetabular impingement syndrome (FAIS)-associated symptoms on clinical outcomes at a minimum of 5 years after hip arthroscopy. We identified FAIS patients who underwent primary hip arthroscopy between January 2012 and January 2014 with a minimum of 5 years' follow-up. Patient demographic characteristics and clinical outcomes, comprising the Hip Outcome Score-Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sports Subscale (HOS-SS), modified Harris Hip Score (mHHS), pain score, and satisfaction score, were analyzed. The minimal clinically important difference, patient acceptable symptomatic state, and substantial clinical benefit were calculated. Patients were stratified based on the preoperative duration of symptoms: less than 2 years versus 2 years or longer. Multivariate regressions were constructed to determine the association between the preoperative symptom duration and clinical outcomes at 5 years after hip arthroscopy. A total of 310 patients were included with a mean age (±standard deviation) of 34.1 ± 11.9 years and body mass index of 25.3 ± 5.1. The study group showed statistically significant improvements in the HOS-ADL, HOS-SS, mHHS, pain score, and satisfaction score (P < .001 for all). A preoperative duration of symptoms of 2 or more years was an independent predictor of worse HOS-ADL, HOS-SS, mHHS, and pain score (P < .05 for all). Furthermore, a longer duration of symptoms was associated with a lower likelihood of achieving the minimal clinically important difference for the HOS-ADL (odds ratio [OR], 0.53; P= .037), HOS-SS (OR, 0.38; P= .003), and mHHS (OR, 0.43; P= .009); the patient acceptable symptomatic state for the HOS-SS (OR, 0.44; P= .006) and mHHS (OR, 0.46; P= .006) but not the HOS-ADL despite trending toward significance (OR, 0.59; P= .098); and substantial clinical benefit for the HOS-ADL (OR, 0.50; P=.011), HOS-SS (OR, 0.52; P= .020), and mHHS (OR, 0.47; P= .007). Patients with a preoperative duration of FAIS-associated symptoms of 2 or more years prior to hip arthroscopy experience inferior outcomes and a lower frequency of clinically significant outcome improvement than patients with a shorter duration of symptoms at medium-to long-term follow-up. Level III, retrospective comparative trial.

Is There an Association Between Preoperative Expectations and Patient-Reported Outcome After Hip Arthroscopy for Femoroacetabular Impingement Syndrome?

To determine the relationship between preoperative patient expectation and postoperative satisfaction and overall patient-reported outcome (PRO) of patients undergoing hip arthroscopy for femoroacetabular impingement syndrome. Patients who underwent hip arthroscopy for femoroacetabular impingement syndrome completed the validated Hip Preservation Surgery Expectations Survey (21 questions; 0-100 range), as well as multiple PROs before surgery. High expectation was defined as an expectation score greater than 1 standard deviation above the mean. Patients with osteoarthritis, dysplasia, and those having undergone previous hip surgery were excluded. At 1year postoperatively, patient visual analog scale (VAS) satisfaction, VAS pain, and PROs were assessed. Univariable and multivariate analyses were performed. One-hundred fifty-three subjects (mean age 34.4 ± 12.6years, female: 114 [71.3%], body mass index: 25.9 ± 5.3kg/m2) participated. The mean expectation score was 84.5 ± 12.3. Significant correlations between high expectation scores (>96.7) and achieving the minimal clinical important difference (MCID) for modified Harris Hip Score (mHHS; r= 0.339; P= .043) and patient acceptable symptomatic state (PASS) for Hip Outcome Score-Activities of Daily Living Subscale (HOS-ADL; r= 0.207; P= .032) were observed. There were no significant correlations between high expectation scores and preoperative or postoperative PROs or patient satisfaction scores. χ2 analysis demonstrated patients with greater expectations had increased rates of reaching MCID mHHS (92.3% vs 74.7%; P= .08), PASS mHHS (85.7% vs 69.7%; P= .046), and PASS HOS-ADL (93.8% vs 67.4%; P= .031). High preoperative expectation is associated with increased rates of MCID/PASS achievement on mHHS and increased rate of PASS achievement on HOS-ADL. Preoperative expectations did not have an impact on Hip Outcome Score-Sports Subscale; however, patients with high preoperative expectations also have a high baseline Hip Outcome Score-Sports Subscale. In addition, preoperative expectations are not associated with postoperative VAS satisfaction scores. III; non-randomized cohort, therapeutic.

Acetabular Morphologic Characteristics Predict Early Conversion to Arthroplasty After Isolated Hip Arthroscopy for Femoroacetabular Impingement

Background: Hip arthroscopy in the setting of dysplasia and borderline dysplasia is controversial. Dysplasia severity is most often defined by the lateral center edge angle (LCEA) but can also be evaluated radiographically by the acetabular inclination (AI). Purpose/Hypothesis: The purpose was to determine the effect of AI on outcomes after isolated hip arthroscopy for femoroacetabular impingement (FAI). We hypothesized that patients with dysplasia would have higher rates of arthroplasty as well as inferior clinical and functional outcomes compared with patients who did not have dysplasia. Study Design: Cohort study; Level of evidence, 3. Methods: A hip arthroscopy registry was reviewed for participants undergoing arthroscopic correction of FAI from February 28, 2008, to June 10, 2013. Participants required a clinical diagnosis and isolated arthroscopic correction of FAI with preoperative imaging and intraoperative cartilage status recorded. AI dysplasia was defined as an AI greater than 10°, LCEA dysplasia as LCEA less than 18°, and borderline LCEA dysplasia as LCEA 18° to 25°. Patients without an acetabular deformity (LCEA 25°-40°; AI <10°) served as a control population. Postoperative variables included patient-reported outcome surveys with conversion to arthroplasty as the primary endpoint. Minimum 5-year outcome scores were obtained for 337 of 419 patients (80.4%) with an average follow-up of 75.2 ± 12.7 months. Results: This study included 419 patients: 9 (2%) with LCEA dysplasia, 42 (10%) with AI dysplasia, and 51 (12%) with borderline dysplasia. The AI but not LCEA was significantly correlated with lower outcome scores on the modified Harris Hip Score (r = 0.13; P = .01), Non-Arthritic Hip Score (r = 0.10; P = .04), and Hip Outcome Score–Sports Subscale (r = 0.11; P = .04). A total of 58 patients (14%) underwent arthroplasty at 31 ± 20 months postoperatively. Patients with LCEA dysplasia had an arthroplasty rate of 56% (odds ratio, 8.4), whereas patients with AI dysplasia had an arthroplasty rate of 31% (odds ratio, 3.3), which was significantly greater than the rate for the nondysplastic cohort (13.5%; P < .0001). Patients with borderline LCEA dysplasia did not have increased rates of arthroplasty. A multivariate analysis found increasing age, increasing AI, Tönnis grade higher than 1, and femoral Outerbridge grade higher than 2 to be most predictive of conversion to arthroplasty. Conclusion: We found that an elevated AI, along with increasing age, Tönnis grade, and femoral Outerbridge grade significantly predict early conversion to arthroplasty after isolated hip arthroscopy. We recommend using the AI, in addition to the LCEA, in evaluating hip dysplasia before hip arthroscopy.

Comparing Outcomes of Competitive Athletes Versus Nonathletes Undergoing Hip Arthroscopy for Treatment of Femoroacetabular Impingement Syndrome

Background: A growing number of studies have examined return to sport in competitive athletes after undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS); however, few have evaluated the rate of achieving meaningful clinical outcomes in this group. Purpose: To determine if competitive athletes (professional, semiprofessional, or collegiate) have better 2-year patient-reported outcomes and achieve the minimal clinically important difference (MCID) and substantial clinical benefit at higher rates when compared with nonathletes undergoing hip arthroscopy for the treatment of FAIS. Study Design: Cohort study; Level of evidence, 3. Methods: The study was a retrospective analysis of all consecutive patients who identified as either a competitive athlete or a nonathlete and had undergone hip arthroscopy for FAIS by a single fellowship-trained surgeon between January 2012 and April 2017. Patients in the 2 groups were matched 1:2 by age, sex, and body mass index. Baseline and clinical outcomes, including the Hip Outcome Score–Activities of Daily Living, Hip Outcome Score–Sports Subscale (HOS-SS), modified Harris Hip Score, and international Hip Outcome Tool-12, were collected preoperatively and at 2 years postoperatively and compared between the groups. The MCID and substantial clinical benefit were calculated for each group separately and compared using chi-square analysis. Results: A total of 59 competitive athletes and 118 nonathletes were included in the final analysis. Most of the competitive athletes were soccer players (23.7%), followed by softball players (10.2%) and runners (10.2%). Postoperative score comparison between competitive athletes and nonathletes demonstrated a statistically significant difference in the HOS-SS (mean ± SD, 84.5 ± 19.0 vs 76.1 ± 23.8; P = .02). Meaningful outcome analysis demonstrated that competitive athletes had a higher rate of achieving the HOS-SS threshold for the MCID (97.4% vs 82.5%; P = .021). There was no other difference in frequency of achieving the threshold for any other meaningful clinical outcome between the groups. Conclusion: Hip arthroscopy for the treatment of FAIS in competitive athletes and nonathletes produced clinically meaningful outcomes in both patient groups. However, competitive athletes achieved the MCID on the HOS-SS at higher rates than nonathletes and had significantly higher scores at 2 years postoperatively on the HOS-SS.

Radiographic Prevalence of Sacroiliac Joint Abnormalities and Clinical Outcomes in Patients With Femoroacetabular Impingement Syndrome

To quantify the prevalence of sacroiliac joint (SIJ) abnormalities in patients undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS) by use of various imaging modalities and to compare outcomes based on SIJ abnormalities. Plain radiographs, computed tomography (CT) scans, and magnetic resonance imaging (MRI) scans of patients who underwent primary hip arthroscopy for FAIS from January 2012 to January 2016 were identified. The exclusion criteria included patients undergoing bilateral or revision surgery, those with a history of dysplasia, and those with less than 2years' follow-up. On radiographs, the SIJs were graded using modified New York criteria for spondyloarthropathy. CT and MRI scans were reviewed for joint surface erosion, subchondral sclerosis, joint space narrowing, pseudo-widening, bone marrow edema, and ankylosis. Patients with SIJ abnormalities were matched to patients without SIJ abnormalities in a 1:2 ratio by age and body mass index. Outcomes included the Hip Outcome Score-Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sports Subscale (HOS-SS), modified Harris Hip Score (mHHS), visual analog scale (VAS) for pain, and VAS for satisfaction. Of 1,009 consecutive patients, 743 (73.6%) were included; 187 (25.2%) showed SIJ changes. Of these 187 patients, 164 (87.7%) had changes on plain radiographs, 88 (47.1%) had changes on CT, and 125 (66.8%) had changes on MRI. SIJ changes on any imaging modality were weakly correlated with pain to palpation of the SIJ (r= 0.11, P=.004) on physical examination. Pain to palpation of the SIJ on physical examination (odds ratio [OR], 1.12; P= .031) and a history of SIJ pain (OR, 1.93; P= .018) increased the odds of having an SIJ abnormality on any imaging modality. After matching, patients without SIJ abnormalities had a significantly greater HOS-ADL (95.4 vs 90.6, P= .001), HOS-SS (91.1 vs 77.5, P < .001), and mHHS (91.3 vs 84.5, P < .001) and a significantly lower VAS pain score (10.9 vs 25.7, P < .001) than patients with abnormalities at a mean follow-up of 34.1 ± 9.7months (range, 24-54months). Patients without SIJ abnormalities had greater odds of achieving the minimal clinically important difference for the HOS-ADL (OR, 2.91; P= .001) and for the HOS-SS (OR, 2.83; P < .001) but not for the mHHS (OR, 1.73; P= .081). A high prevalence of SIJ abnormalities (25.2%) is seen on imaging in FAIS patients. These patients may show significantly inferior clinical outcomes and persistent postoperative pain after FAIS treatment. The results of this study may allow treating orthopaedic surgeons to better inform patients with SIJ abnormalities that they may not achieve clinically significant outcome improvement after hip arthroscopy. Level III, retrospective comparative study.

Prevalence and Clinical Implications of Chondral Injuries After Hip Arthroscopic Surgery for Femoroacetabular Impingement Syndrome

Background: Studies on the effect of partial- and full-thickness chondral damage of the hip on outcomes and the ability to achieve meaningful clinical outcomes are limited. Purpose: To determine the effect of full- and partial-thickness chondral injuries on 2-year outcomes in patients undergoing hip arthroscopic surgery for femoroacetabular impingement syndrome (FAIS) compared with patients without chondral damage, and to identify significant predictors of achieving the patient acceptable symptomatic state (PASS) and minimal clinically important difference (MCID). Study Design: Case-control study; Level of evidence, 3. Methods: Data from consecutive patients with evidence of chondromalacia at the time of primary hip arthroscopic surgery with routine capsular closure for the treatment of FAIS by a single fellowship-trained surgeon between January 2012 and September 2016 were reviewed. Patients were divided into groups with partial-thickness (grade I-III) or full-thickness (grade IV) chondral defects and matched by age and body mass index (BMI) to patients without chondral injuries. Preoperative and postoperative outcomes were compared among the 3 groups, and a binary logistic regression analysis was utilized to identify significant predictors of achieving the MCID and PASS. Results: There were 634 patients included in the analysis, with a mean age of 34.5 ± 10.9 years and a mean BMI of 25.2 ± 4.7 kg/m2. A total of 493 (77.8%) patients had no evidence of chondral damage, 92 (14.5%) patients had partial-thickness chondral defects, and 49 (7.7%) patients had full-thickness chondral defects. There were statistically significant differences in the Hip Outcome Score (HOS)–Activities of Daily Living, HOS–Sports Subscale, modified Harris Hip Score, pain, and satisfaction (P < .01) among the 3 groups. Patients with grade IV chondromalacia experienced the poorest outcomes and lowest percentage of achieving the PASS. Predictors for achieving any PASS threshold included preoperative alpha angle (odds ratio [OR], 0.96; P = .016), absence of preoperative limping (OR, 7.25; P = .002), absence of preoperative chronic pain (OR, 5.83; P = .019), primary hip arthroscopic surgery (OR, 0.17; P = .050), patients who self-identified as runners (OR, 2.27; P = .037), and Tönnis grade 0 (OR, 2.86; P = .032). Male sex (OR, 2.49; P = .015) was the only predictor of achieving any MCID threshold. Conclusion: Patients with grade IV chondral defects experienced worse functional outcomes, lower satisfaction, and increased pain when compared with both patients without chondral damage or grade I-III chondromalacia at 2-year follow-up. Several predictors were associated with achieving clinically significant function in patients undergoing hip arthroscopic surgery for FAIS.

Midterm Outcomes of Iliopsoas Fractional Lengthening for Internal Snapping as a Part of Hip Arthroscopy for Femoroacetabular Impingement and Labral Tear: A Matched Control Study

To report minimum 5-year outcomes and rate of painful snapping resolution for patients who underwent iliopsoas fractional lengthening (IFL) as a part of hip arthroscopy for femoroacetabular impingement (FAI) and labral tear. In addition, to match this group to a group of patients who underwent hip arthroscopy for FAI and labral tear without internal snapping. Patients were eligible for inclusion if they underwent hip arthroscopy for treatment of FAI and labral tear with concomitant IFL for painful snapping and had preoperative baseline scores for modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score-Sports Subscale, and visual analog scale for pain. The exclusion criteria for this study were preoperative Tönnis grade >0, active workers' compensation claims, or previous ipsilateral hip conditions. These patients were matched to a control group of patients who did not have snapping or undergo IFL but who otherwise satisfied the same inclusion and exclusion criteria. There were 57 eligible cases (80.3% follow-up). Mean follow-up time was 69.3months (from 60.0 to 91.9). All patient-reported outcomes measures demonstrated statistically significant improvements between preoperative and latest follow-up scores for the following measures (P<.001): modified Harris Hip Score (from 64.3 to 84.9), Nonarthritic Hip Score (from 61.7 to 85.2), Hip Outcome Score-Sports Subscale (from 47.0 to 75.0), and visual analog scale (from 6.5 to 2.2). Mean satisfaction was 8.1 out of 10. Painful snapping was resolved in 80.7% of cases. Ten hips (17.5%) required secondary arthroscopy at a mean of 30.5months. Three hips (5.3%) required total hip arthroplasty at a mean of 57.5months. One case (1.8%) had minor postoperative complications. There were no statistically significant differences between the groups in outcomes, complications, and secondary surgeries. IFL as part of hip arthroscopy for treatment of FAI and labral tears demonstrated similar favorable improvement, complication rates, and secondary surgeries, when compared with a control group that did not undergo IFL. Level III, retrospective comparative study.

Influence of Acetabular Labral Tear Length on Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome With Capsular Plication

Background: The literature on the effects of labral tear on patient-reported outcomes, midterm pain, and overall patient satisfaction is limited. Purpose: To determine the effect of labral tear length on postoperative outcomes after hip arthroscopy for femoroacetabular impingement syndrome (FAIS). Study Design: Cohort study; Level of evidence, 3. Methods: Consecutive patients undergoing primary hip arthroscopy for FAIS from January 2012 to January 2016 were identified in a prospectively collected database. All patients completed the Hip Outcome Score–Activities of Daily Living (HOS-ADL), Hip Outcome Score–Sports Subscale (HOS-SS), modified Harris Hip Score (mHHS), and visual analog scale for pain and satisfaction. Patients were stratified by labral tear length into small (<2.5 cm) or large (≥2.5 cm) based on the receiver operating characteristic curve analysis. Patient characteristics and outcomes were analyzed with multivariate linear regression analyses to identify predictors of labral tear length. Binary logistic regression analysis was performed to determine whether labral tear length predicted the likelihood of achieving the minimal clinically important difference. Results: Of the 747 eligible patients, 600 (80.3%) had 2-year reported outcomes and were included in the final analysis. Mean age, body mass index, and tear length were 33.5 ± 12.3 years, 25.4 ± 9.2 kg/m2, and 2.7 ± 0.7 cm, respectively. Men had higher frequency of large tears when compared with women (77% vs 43.7%, P < .001). Independent t test demonstrated significant differences in 2-year outcomes between patients with tears <2.5 and ≥2.5 cm, respectively: HOS-ADL (87.3 ± 16.3 vs 84.3 ± 18.1, P = .033), HOS-SS (76.6 ± 23.5 vs 70.5 ± 27.7, P = .005), mHHS (82.5 ± 18.0 vs 78.5 ± 18.2, P = .009), and satisfaction (83.5 ± 23.4 vs 77.8 ± 34.9, P = .026). Binary logistic regression analysis demonstrated that labral tear length is an independent predictor of visual analog scale for satisfaction, HOS-ADL, HOS-SS, and mHHS. Binary logistic regression analysis demonstrated that patients with small labral tears had a higher likelihood of achieving the minimal clinically important difference for the HOS-SS (odds ratio, 1.61; 95% CI, 1.39-1.92; P < .02) and the patient acceptable symptomatic state for the mHHS (odds ratio, 1.56; 95% CI, 1.11-2.2; P = .038) than those with larger tears. Conclusion: Labral tear length is independently predictive of patient-reported outcomes after hip arthroscopy for FAIS. Furthermore, patients with smaller tears (<2.5 cm) had better outcomes and a higher likelihood of achieving a minimal clinically important difference at 2-year follow-up. However, the mean differences between changes in pre- and postoperative outcomes were relatively small and may not be clinically meaningful.

Radiographic and Clinical Outcomes of Adolescents With Acetabular Retroversion Treated Arthroscopically.

Retroversion of the acetabulum is a cause of pincer impingement. Symptomatic retroversion has traditionally been treated with anteverting periacetabular osteotomy (PAO). However, arthroscopic rim trimming can also treat pincer impingement associated with acetabular retroversion. The purpose of this study was to report the outcomes and radiographic findings in a series of adolescent patients with symptomatic acetabular retroversion treated arthroscopically. Data were prospectively gathered at a single institution using an established hip preservation registry. Patients below 18 years with a retroverted acetabulum that underwent primary hip arthroscopy with 2-year follow-up were included. Acetabular retroversion was defined by 3 radiographic criteria: the presence of crossover, ischial spine sign, and posterior wall sign. Radiographic measurements of the lateral center-edge angle, anterior center-edge angle, alpha angle, and crossover percentage were reported preoperatively and postoperatively. Patient-reported outcome (PROs) measures included the modified Harris Hip Score, the non-Arthritic Hip Score, Hip Outcome Score Sports Subscale, visual analog scale, and patient satisfaction, recorded at 3 months, 1 year, and 2 years, postoperatively. In addition, International Hip Outcome Tool scores were gathered at 2 years. Between April 2008 and July 2014, there were 43 patients (48 hips) treated with hip arthroscopy who met the inclusion criteria. The average age was 16.1 years (range, 13.9 to 17.9 y) and there were 38 females and 10 males. The average follow-up was 50.4 months, with a minimum of 2 years. Statistically significant improvements in all PROs were found at 2 years postoperatively. There were 9 hips with lateral center-edge angle ≤25 degrees; the PROs of this group was not different than patients with normal coverage. Three patients underwent arthroscopic revision. No patient subsequently underwent anteverting PAO during the study period. There were no reported complications. Femoroacetabular impingement caused by acetabular retroversion treated with hip arthroscopy demonstrates good outcomes at 2 years with a low complication rate. Symptomatic adolescents may be safely and successfully treated arthroscopically, potentially avoiding anteverting PAO. Level of evidence 4-case series.

A Comparison of Clinical Outcomes After Unilateral or Bilateral Hip Arthroscopic Surgery: Age- and Sex-Matched Cohort Study

Background: A significant number of patients undergoing hip arthroscopic surgery for femoroacetabular impingement (FAI) have bilateral deformities and may require surgery for both hips. Purpose: To compare outcomes between patients who underwent bilateral hip arthroscopic surgery to a matched cohort of patients who underwent unilateral hip arthroscopic surgery. Study Design: Cohort study; Level of evidence, 3. Methods: A consecutive series of patients who underwent primary hip arthroscopic surgery for FAI by a single fellowship-trained surgeon from January 2012 to January 2014 and had a minimum follow-up of 2 years were evaluated. Patients who underwent staged bilateral hip arthroscopic surgery were identified and matched 1:2 to patients who underwent unilateral hip arthroscopic surgery based on age, sex, and body mass index (BMI). Demographic, preoperative, and postoperative variables were compared between the groups. Results: Forty-three patients in the bilateral group were matched with 86 patients in the unilateral group based on sex (24 female [56%] vs 48 female [56%], respectively; P > .99), age (28.6 ± 10.8 years vs 28.9 ± 10.8 years, respectively; P = .88), and BMI (24.8 ± 5.8 kg/m2 vs 24.8 ± 4.0 kg/m2, respectively; P = .98). There were no significant preoperative demographic or radiographic differences between the groups. Both groups demonstrated significant preoperative to postoperative improvements in the Hip Outcome Score–Activities of Daily Living (HOS-ADL), Hip Outcome Score–Sports Subscale (HOS-SS), and modified Harris Hip Score (mHHS) (P < .0001 for all). When compared with patients in the unilateral group, patients who underwent bilateral hip arthroscopic surgery had less improvement in mHHS and pain scores. Sixty-five (76%) patients in the unilateral group achieved the minimum clinically important difference (MCID) for the mHHS compared with 21 (49%) in the bilateral group (P = .03), while 64 (74%) patients achieved the patient acceptable symptomatic state (PASS) for the mHHS compared with 22 (51%) in the bilateral group (P = .02). Patients in the bilateral group with greater than 10 months between surgical procedures had lower postoperative HOS-ADL scores (P = .04) and lower improvement in pain and HOS-SS scores (P < .0001 and P = .05, respectively). Conclusion: Patients who underwent unilateral and bilateral hip arthroscopic surgery for FAI had improved functional outcomes after 2 years. However, patients who underwent bilateral hip arthroscopic surgery had less improvement in their mHHS and pain scores compared with those who underwent unilateral hip arthroscopic surgery but no differences in HOS-ADL, HOS-SS, or satisfaction scores. Patients in the bilateral group with longer than 10 months between surgical procedures had lower outcome scores than patients who underwent their second surgical procedure within 10 months of their primary surgery.

Predictors of Inferior Outcomes Following Hip Arthroscopy for Femoroacetabular Impingement

Objectives:Hip arthroscopy for femoroacetabular impingement (FAI) provides reliable pain relief and functional improvement in the majority of patients. Although a small percentage of patients will go on to subsequent revision hip arthroscopy or conversion to arthroplasty, some patients will also have inferior clinical outcome without revision surgery. The purpose of this study is to identify clinical and radiographic characteristics predictive of inferior outcomes 2-years following hip arthroscopy for FAI.Methods:A clinical repository containing patients undergoing primary hip arthroscopy for femoroacetabular impingement (FAI) between 1/1/2012-1/1/2014 with a minimum follow up of two years was queried to include patients in this study. Operative procedures generally included labral debridement and repair, acetabular rim trimming, femoral osteochondroplasty and capsular plication. The primary outcome measure was the Hip Outcome Score Activities of Daily Living (HOS-ADL) questionnaire. Secondary outcome measures included the Hip Outcome Score Sports Subscale (HOS-SS) and modified Harris Hip Score (MHHS). Patients requiring revision hip arthroscopy or hip arthroplasty were excluded from this study. Patients were organized into superior and inferior outcome groups based on the top and bottom quartiles of the postoperative HOS-ADL score. Demographic, preoperative, intraoperative and postoperative variables between these groups were compared to identify predictors for inferior outcomes using bivariate and multivariate analyses.Results:Of 482 patients undergoing hip arthroscopy for FAI there was two year outcome data for 392 patients (81.5%) with an average follow up of 2.3 ± 0.6 years. The superior group contained 98 patients with an HOS-ADL score of 97.06 or higher while the inferior group contained 98 patients with an HOS-ADL score of 80.5 or lower. Patients in the superior outcome group were younger (30.7 ± 12.8 vs 38.0 ± 11.8 p<0.001) with a lower BMI (24.1 ± 4.1 vs. 26.5 ± 5.1 p=0.005) and higher preoperative average joint space width (4.2 ± 0.5 mm vs. 3.7 ± 0.4 mm; p=0.009) and lower Tonnis grade (p<0.001; Table 1). Patients in the inferior outcome group also had a higher incidence of smoking (p=0.005), workers compensation claims (p=0.04) and prior psychiatric history (p=0.007). A stepwise multivariate logistic regression analysis revealed that older age (p=0.00674), higher BMI (p=0.02629), and smoking (p=0.01863) were independent predictive factors of inferior outcome (Table 1). Both groups demonstrated significant improvements in HOS-ADL, and MHHS scores, however the inferior outcome group did not have significantly improved HOS-SS scores (p=0.06).Table 1:Demographic and radiographic differences between superior and inferior outcome groups following hip arthroscopy for Femoroacetabular Impingement Inferior OutcomeSuperior OutcomepAge38.0 ± 11.830.7 ± 12.8 <0.0001 Tonnis Grade > 019 (22%)1 (1.1%) <0.0001 Postoperative Alpha Angle42.3 ± 4.438.4 ± 3.7 0.001 BMI26.5 ± 5.124.1 ± 4.1 0.005 Smoking14(14%)3 (3%) 0.005 Preoperative Joint Space (mm)4.2 ± 0.543.75 ± 0.41 0.009 Psychiatric History27 (28%)12(12%) 0.02 Workers Compensation8(8.4%)2 (2.0%) 0.04 Spine History18 (19%)11(11%)0.16Gender (%F)60(61%)55 (56%)0.47Postoperative LCEA29.4 ± 4.530.1 ± 4.00.56Preoperative LCEA32.54 ± 5.732.16 ± 0.530.62Preoperative Alpha Angle61.5 ± 10.361.2 ± 9.30.83Conclusion:Older age, higher BMI, and smoking were independent predictors of inferior clinical outcomes at 2-years following hip arthroscopy for FAI, although both superior and inferior outcome groups experienced significantly improved clinical outcome scores. In addition, lower preoperative joint space, workers compensation status, and psychiatric history were significant factors for inferior outcomes on bivariate analysis. These factors can be considered in preoperative patient counseling about the expected outcome of hip arthroscopy for FAI.

Revision Hip Arthroscopy

Background: As the number of hip arthroscopic surgeries being performed increases, so too does the prevalence of revision hip arthroscopic surgery. Hypothesis/Purpose: The purpose of this study was to compare outcomes in patients requiring revision hip arthroscopic surgery to patients undergoing primary hip arthroscopic surgery. The hypothesis was that patients undergoing revisions would demonstrate similar outcomes to those undergoing primary hip arthroscopic surgery. Study Design: Cohort study; Level of evidence, 2. Methods: Included in the study were patients undergoing revision hip arthroscopic surgery who did not have a history of prior open hip surgery. Each patient in the revision cohort was matched with 2 patients undergoing primary hip arthroscopic surgery. Preoperatively and at a minimum follow-up of 2 years, outcome scores were collected, including the Hip Outcome Score–Activities of Daily Living subscale (HOS-ADL), which was the primary outcome variable; modified Harris hip score (mHHS); Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC); Hip Outcome Score–Sports subscale (HOS-Sports); and the 12-Item Short Form Health Survey (SF12). At follow-up, scores from the Tegner activity scale and patient self-reported satisfaction with surgical outcome were also collected. Results: A total of 246 patients in the revision cohort were matched with 492 patients in the primary cohort. In the revision cohort, 183 patients had 1 prior surgery, 45 had 2 surgeries, and 18 had ≥3 prior surgeries. Subsequent hip arthroscopic surgery was reported in 39 of 492 (8%) patients in the primary cohort and 5 of 246 (2%) patients in the revision cohort (P = .001). Subsequent surgery was reported in 50 of 492 (10%) patients in the primary cohort and 15 of 246 (6%) patients in the revision cohort (P = .07). Both groups saw significant improvement in outcome scores from preoperation to follow-up. The HOS-ADL was lower in the revision cohort preoperatively (65 vs 70) and postoperatively (79 vs 87) (P = .001). This was also seen in the HOS-Sports, WOMAC, and SF12 physical component scores. Patients who had 1 prior hip arthroscopic procedure had higher postoperative mHHS (81 vs 75) compared with patients with >1 hip arthroscopic procedure; however, there was no difference in postoperative mHHS between the single-revision cohort and the primary cohort. In the revision group, patients whose HOS-ADL improved ≥10 points had greater joint space. Patients with greater improvement were more likely to have had a previous labral tear that was not repaired and to require capsular plication at revision. Conclusion: Patients who underwent revision hip arthroscopic surgery had significant improvement in outcome scores but did have lower scores compared with patients with primary hip arthroscopies. Patients with ≥2 revisions had lower outcomes. Improvement in the revision cohort was seen in patients with increased joint space, no prior labral repair, and capsular plication at revision.