Survivorship and Outcome of Hip Arthroscopy for Femoroacetabular Impingement Syndrome Performed With Modern Surgical Techniques

High Survival Rate and Satisfaction at more than 11 years of follow-up of Hip Arthroscopy for Femoroacetabular Impingement Syndrome: Impact of Preoperative Functional Scores, Osteoarthritis, and Chondrolabral Junction Damage on Failure Long-Term 72.6% Survival in Hip Arthroscopy

PURPOSE

The purpose of the study was to investigate the survival and durability of clinical improvements following hip arthoscopy (HA) for femoroacetabular impingement syndrome (FAIS) at a minimum of 10-year follow-up. The primary objective was to determine the long-term survival, defined as: lack of conversion to total hip replacement (THR) or subsequent hip joint preservation surgery (HJPS). The secondary objective was to determine which preoperative factors were predictive of failure.

METHODS

Data from patients who underwent HA for FAIS between March 2003 and May 2012 were collected and retrospectively reviewed. Patients who underwent evaluation at a minimum 10-year follow-up, assessed according to hip outcome score - activities of daily living (HOS-ADL) and sport-specific subscale (HOS-SSS), and non-arthritic hip score (NAHS) were included. Satisfaction ratings were collected. Statistical analysis assessed within-group differences and survival.

RESULTS

95 patients with an average follow-up of 11.8 years were included. Mean age was 39.5 ± 11.0 years. Overall THR conversion rate was 24.2%, with a mean time of 3.4 ± 3.2 years. 3.2% required HJPS revision at a mean 3.2 ± 3 years. Survivorship was 72.6% at ten years. 28 patients (73.6% and 75.6%) achieved the minimal clinically important difference (MCID) for HOS-ADL and HOS-SSS, while 33 (84.6%) for NAHS. Patient Acceptable Symptom State (PASS) was achieved by 42 (61.7%), 43 (65.1%) and 44 (64.7%) patients respectively. Comparative analysis between patients who preserved their hip and those who underwent HJPS revision or THR highlighted that Tönnis ≥ 2, chondrolabral junction damage, and lower preoperative scores are associated with failure.

CONCLUSION

HA for FAIS demonstrated durable results, with an accepatable THR conversion rate and sustained clinical benefits. 91.3% of the patients who preserved their hip were satisfied. Tönnis 2, MRA signs of chondrolabral junction damage and lower preoperative functional status are strongly associated with failure.

Minimal Clinically Important Difference, Substantial Clinical Benefit, and Patient Acceptable Symptom State Values After Hip Arthroscopy for Femoroacetabular Impingement Are Highly Dependent on Their Study Population and Calculation Methods: A Systematic Review

PURPOSE

To provide a summary of available literature on the minimal clinically important difference (MCID), substantial clinical benefit (SCB), and patient acceptable symptom state (PASS) after hip arthroscopy for femoroacetabular impingement (FAI).

METHODS

A systematic review was conducted via the Cochrane Library, PubMed, Ovid MEDLINE, and Embase to identify studies that calculated MCID, SCB, or PASS for patient-reported outcome measures after hip arthroscopy for FAI. The electronic search strategy used was as follows: hip AND arthroscopy AND (MCID OR "minimal clinically important difference" OR SCB OR "substantial clinical benefit" OR PASS OR "patient acceptable symptom state"). Inclusion criteria were English-language studies published from 1980 to 2023 reporting clinical outcome scores and calculated values of MCID, PASS, or SCB for patients undergoing hip arthroscopy for FAI.

RESULTS

Forty-two studies (5 Level II, 19 Level III, and 18 Level IV) met inclusion and exclusion criteria. The most commonly used outcome measures across MCID, SCB, and PASS were the Hip Outcome Score sports-specific subscale and the activities of daily living subscale, the modified Harris Hip Score, and the 12-item international Hip Outcome Tool. The range of MCID values for Hip Outcome Score sports-specific subscale, Hip Outcome Score activities of daily living subscale, modified Harris Hip Score, and 12-item international Hip Outcome Tool were 7.2-15.7, 7.3-15.4, 7.2-16.8, and 8.8-16.2 respectively. Similarly, for SCB the values ranged from 77.9-96.9, 90.4-98.5, 20.0-98.4, and 66.7-87.5, respectively. Lastly, the PASS values ranged from 63.9-80.9, 85.9-99.2, 74.0-97.0, and 59.5-86.0, respectively.

CONCLUSIONS

MCID, SCB, and PASS values for patient-reported outcome measures after hip arthroscopy for the management of FAI are highly dependent on their associated study including study population and calculation methods.

LEVEL OF EVIDENCE

IV, systematic review of Level II-IV studies.

Socioeconomic Factors Including Patient Income, Education Level, and Health Insurance Influence Postoperative Secondary Surgery and Hospitalization Rates Following Hip Arthroscopy

PURPOSE

To evaluate a large cross-sectional sample of patients utilizing administrative database records and analyze the effects of income, insurance type, and education level on outcomes after hip arthroscopy, including 2-year revision surgery, conversion to total hip arthroplasty (THA), and 90-day hospitalizations.

METHODS

Current Procedural Terminology codes were used to query the PearlDiver Mariner database from October 2015 to January 2020 for patients undergoing hip arthroscopy with a minimum 2-year follow-up. Patients were categorized by mean family income in their zip code of residence (MFIR), health insurance type, and educational attainment in their zip code of residence (EAR). Two-year revision arthroscopy, conversion to THA, and 90-day hospital readmissions or emergency department (ED) visits were analyzed along socioeconomic strata.

RESULTS

Multivariate analysis of 33,326 patients revealed that patients with MFIR between $30,000 and $70,000 had lower odds of 2-year revision arthroscopy (odds ratio [OR], 0.63; P < .001), THA conversion (OR, 0.76; P = .050), and 90-day readmission (OR, 0.53; P = .007) compared to MFIR >$100,000. Compared to patients with commercial insurance, patients with Medicare had lower odds of revision arthroscopy (OR, 0.60; P = .035) and THA conversion (OR, 0.46, P < .001) but greater odds of 90-day readmission (OR, 1.74; P = .007). Patients with Medicaid had higher odds of 90-day ED visits (OR, 1.84; P < .001). Patients with low EAR had higher odds of revision arthroscopy (OR, 1.42; P = .005) and THA conversion (OR, 1.58; P = .002) compared to those with high EAR.

CONCLUSIONS

Following hip arthroscopy, patients residing in areas with lower mean family income were less likely to undergo reoperations and readmissions. Medicare patients showed lower reoperation but higher readmission odds, while Medicaid patients showed higher odds of ED visits. Additionally, higher educational attainment in the zip code of residence is protective against future reoperation.

LEVEL OF EVIDENCE

Level III, retrospective case series.

Six-Month Outcomes Correlate With 10-Year Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome

PURPOSE

To identify whether 6-month outcomes after hip arthroscopy for femoroacetabular impingement syndrome (FAIS) correlate with outcomes at minimum 10-year follow-up.

METHODS

Patients who underwent primary hip arthroscopy for FAIS from 2012 to 2013 were reviewed and included if they had 6-month and minimum 10-year follow-up. Patient-reported outcome (PRO) measures included the Hip Outcome Score Activities of Daily Living (HOS-ADL) subscale, Hip Outcome Score Sports-Specific (HOS-SS) subscale, modified Harris Hip Score (mHHS), visual analog scale (VAS) for pain, and VAS for satisfaction. We compared 6-month and 10-year outcome scores and analyzed the relations between 6-month and 1-, 2-, 5-, and 10-year outcome scores using Pearson correlation coefficients (r). Six-month scores and clinically significant outcome achievement were then compared with 10-year clinically significant outcome achievement and reoperations, including revision hip arthroscopy and conversion to total hip arthroplasty (THA), using logistic regressions and the Fisher exact test.

RESULTS

This study included 60 patients (60.0% female sex; mean age, 36.0 ± 12.2 years). The mHHS, VAS pain score, and VAS satisfaction score significantly improved from 6-month to 10-year follow-up (P ≤ .021), whereas the HOS-ADL and HOS-SS did not (P ≥ .072). There were significant correlations between 6-month and 10-year scores for the HOS-ADL (r = 0.505), HOS-SS (r = 0.592), and mHHS (r = 0.362) (P ≤ .022 for all), as well as significant correlations between 6-month and 1-, 2-, and 5-year scores (P ≤ .014 for all). The 6-month HOS-ADL, HOS-SS, and mHHS were all significantly associated with their respective 10-year achievement of the patient acceptable symptom state (PASS) (P ≤ .044). Furthermore, 6-month HOS-ADL and mHHS were significantly associated with THA conversion (P ≤ .041). Comparable 6-month and 10-year achievement of the minimal clinically important difference (96.5% vs 97.8%, P > .999) and PASS (85.2% vs 87.5%, P > .999) for any PRO was observed.

CONCLUSIONS

After hip arthroscopy for FAIS, patients' 6-month HOS-ADL and mHHS were significantly associated with their 10-year PROs, PASS achievement, and THA conversion, although correlation strengths decreased with increasing time from surgery.

LEVEL OF EVIDENCE

Level IV, case series.

Defining Patient-relevant Thresholds and Change Scores for the HOOS JR and KOOS JR Anchored on the Patient-acceptable Symptom State Question

BACKGROUND

When evaluating the results of clinical research studies, readers need to know that patients perceive effect sizes, not p values. Knowing the minimum clinically important difference (MCID) and the patient-acceptable symptom state (PASS) threshold for patient-reported outcome measures helps us to ascertain whether our interventions result in improvements that are large enough for patients to care about, and whether our treatments alleviate patient symptoms sufficiently. Prior studies have developed the MCID and PASS threshold for the Hip Disability and Osteoarthritis Outcome Score for Joint Replacement (HOOS JR) and Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) anchored on satisfaction with surgery, but to our knowledge, neither the MCID nor the PASS thresholds for these instruments anchored on a single-item PASS question have been described.

QUESTIONS/PURPOSES

(1) What are the MCID (defined here as the HOOS/KOOS JR change score associated with achieving PASS) and PASS threshold for the HOOS JR and KOOS JR anchored on patient responses to the single-item PASS instrument? (2) How do patient demographic factors such as age, gender, and BMI correlate with MCID and PASS thresholds using the single-item PASS instrument?

METHODS

Between July 2020 and September 2021, a total of 10,970 patients underwent one primary unilateral THA or TKA and completed at least one of the three surveys (preoperative HOOS or KOOS JR, 1-year postoperative HOOS or KOOS JR, and 1-year postoperative single-item anchor) at one large, academic medical center. Of those, only patients with data for all three surveys were eligible, leaving 13% (1465 total; 783 THAs and 682 TKAs) for analysis. Despite this low percentage, the overall sample size was large, and there was little difference between completers and noncompleters in terms of demographics or baseline patient-reported outcome measure scores. Patients undergoing bilateral total joint arthroplasty or revision total joint arthroplasty and those without all three surveys at 1 year of follow-up were excluded. A receiver operating characteristic curve analysis, leveraging a 1-year, single-item PASS (that is, "Do you consider that your current state is satisfactory?" with possible answers of "yes" or "no") as the anchor was then used to establish the MCID and PASS thresholds among the 783 included patients who underwent primary unilateral THA and 682 patients who underwent primary unilateral TKA. We also explored the associations of age at the time of surgery (younger than 65 years or 65 years and older), gender (men or women), BMI (< 30 or ≥ 30 kg/m 2 ), and baseline Patient-Reported Outcome Measure Information System-10 physical and mental component scores (< 50 or ≥ 50) for each of the MCID and PASS thresholds through stratified analyses.

RESULTS

For the HOOS JR, the MCID associated with the PASS was 23 (95% CI 18 to 31), with an area under the receiver operating characteristic curve of 0.75, and the PASS threshold was 81 (95% CI 77 to 85), with an area under the receiver operating characteristic curve of 0.81. For the KOOS JR, the MCID was 16 (95% CI 14 to 18), with an area under the receiver operating characteristic curve of 0.75, and the PASS threshold was 71 (95% CI 66 to 73) with an area under the receiver operating characteristic curve of 0.84. Stratified analyses indicated higher change scores and PASS threshold for younger men undergoing THA and higher PASS thresholds for older women undergoing TKA.

CONCLUSION

Here, we demonstrated the utility of a single patient-centered anchor question, raising the question as to whether simply collecting a postoperative PASS is an easier way to measure success than collecting preoperative and postoperative patient-reported outcome measures and then calculating MCIDs and the substantial clinical benefit.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Association Between Chondrolabral Junction Breakdown and Conversion to Total Hip Arthroplasty After Hip Arthroscopy for Symptomatic Labral Tears: Minimum 8-Year Follow-up

BACKGROUND

Arthroscopic treatment of femoroacetabular impingement (FAI) and symptomatic labral tears confers short- to midterm benefits, yet further long-term evidence is needed. Moreover, despite the physiological and biomechanical significance of the chondrolabral junction (CLJ), the clinical implications of damage to this transition zone remain understudied.

PURPOSE

To (1) report minimum 8-year survivorship and patient-reported outcome measures after hip arthroscopy for FAI and (2) characterize associations between outcomes and patient characteristics (age, body mass index, sex), pathological parameters (Tönnis angle, alpha angle, type of FAI, CLJ breakdown), and procedures performed (labral management, FAI treatment, microfracture).

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

This retrospective cohort study included patients who underwent primary hip arthroscopy for symptomatic labral tears secondary to FAI by a single surgeon between 2002 and 2013. All patients were ≥18 years of age with minimum 8-year follow-up and available preoperative radiographs. The primary outcome was conversion to total hip arthroplasty (THA), and secondary outcomes included revision arthroscopy, patient-reported outcome measures, and patient satisfaction. CLJ breakdown was assessed using the Beck classification. Kaplan-Meier estimates and weighted Cox regression were used to estimate 10-year survivorship (no conversion to THA) and identify risk factors associated with THA conversion.

RESULTS

In this study of 174 hips (50.6% female; mean age, 37.8 ± 11.2 years) with mean follow-up of 11.1 ± 2.5 years, the 10-year survivorship rate was 81.6% (95% CI, 75.9%-87.7%). Conversion to THA occurred at a mean 4.7 ± 3.8 years postoperatively. Unadjusted analyses revealed several variables significantly associated with THA conversion, including older age; higher body mass index; higher Tönnis grade; labral debridement; and advanced breakdown of the CLJ, labrum, or articular cartilage. Survivorship at 10 years was inferior in patients exhibiting severe (43.6%; 95% CI, 31.9%-59.7%) versus mild (97.9%; 95% CI, 95.1%-100%) breakdown of the CLJ (P < .001). Multivariable analysis identified worsening CLJ breakdown (weighted hazard ratio per 1-unit increase, 6.41; 95% CI, 3.11-13.24), older age (1.09; 95% CI, 1.04-1.14), and higher Tönnis grade (4.59; 95% CI, 2.13-9.90) as independent negative prognosticators (P < .001 for all).

CONCLUSION

Although most patients achieved favorable minimum 8-year outcomes, several pre- and intraoperative factors were associated with THA conversion; of these, worse CLJ breakdown, higher Tönnis grade, and older age were the strongest predictors.

Increasing Hip Arthroscopy Case Volume Is Associated With Increased Risk for Revision Surgery but Not Conversion to Total Hip Arthroplasty or 90-Day Hospitalizations: A Cross-Sectional Analysis of 468 Surgeons

PURPOSE

To analyze the effects of surgeon-specific factors, including case volume, career duration, fellowship training, practice type, and region of practice, on rates of 2-year revision surgery, conversion to total hip arthroplasty (THA), and 90-day hospitalizations following hip arthroscopy.

METHODS

The PearlDiver Mariner Database was used to query patients undergoing hip arthroscopy between 2015 and 2018. Surgeons performing these procedures were identified, and surgeon-specific demographics and variables were collected from publicly available data. Patients were followed for 2 years to assess for reoperations, including revision hip arthroscopy and conversion to THA, as well as 90-day hospitalizations, including emergency department visits and hospital readmissions. International Classification of Diseases, Tenth Revision codes were used to track the laterality of revision hip procedures. Associations between surgeon-specific factors and postoperative outcomes were assessed through univariate and multivariate analyses.

RESULTS

In total, 20,834 patients underwent hip arthroscopy procedures by 468 surgeons. Multivariate analysis with logistic regression adjusted for patient-related factors (age, sex, obesity, Charlson Comorbidity Index, and smoking status) identified increasing surgeon case volume to be associated with increased risk for 2-year revision hip arthroscopy (P < .001), but not 2-year conversion to THA or 90-day hospitalizations. Nonsports medicine fellowship-trained surgeons were associated with greater risk for 2-year THA conversion (P < .001) and 90-day hospital readmissions (P < .01). Surgeons practicing in an academic setting demonstrated greater risk for 90-day hospital readmissions (P < .001). Surgeons practicing in the West region of the United States were more likely to incur 2-year revision hip arthroscopy procedures compared to surgeons in the South, Midwest or Northeast (P < .001).

CONCLUSIONS

Increasing surgeon hip arthroscopy case volume is associated with an increased risk for 2-year revision hip arthroscopy but not conversion to THA or 90-day hospitalizations. Further, non-sports medicine fellowship-trained surgeons were associated with higher risk for 2-year THA conversion after hip arthroscopy.

LEVEL OF EVIDENCE

Level III, retrospective cohort analysis.

Cartilage Defects Are Negatively Associated With Long-Term Hip Survivorship Following Contemporary Hip Arthroscopy for Femoroacetabular Impingement Syndrome: A Propensity-Matched Analysis at Minimum 10-Year Follow-Up

PURPOSE

To identify the timing and risk factors associated with secondary surgery following primary hip arthroscopy for femoroacetabular impingement syndrome (FAIS) at 10-year minimum follow-up.

METHODS

A prospectively collected clinical repository was evaluated for cases of primary hip arthroscopy for FAIS between January 2012 and February 2013 with minimum 10-year follow-up. Patients who underwent secondary surgery were propensity matched 1:4 to patients who did not undergo secondary surgery, controlling for age, sex, and body mass index (BMI). The groups were compared on demographics, radiographs, intraoperative findings, operative procedures, and patient-reported outcomes. A Kaplan-Meier survivorship curve was generated. Among the reoperation-free survivors, minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) achievement were recorded for Hip Outcome Score-Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sports Specific (HOS-SS) subscales, modified Harris Hip Score (mHHS), 12-item international Hip Outcome Tool (iHOT-12), and Visual Analog Scale for Pain (VAS Pain).

RESULTS

Twenty-four reoperation patients (67% female; age 40.1 ± 14.3 years; BMI 27.2 ± 5.5) were matched to 96 reoperation-free patients (62% female; age 37.0 ± 10.8 years; BMI 25.2 ± 4.7, P ≥ .111). Mean follow-up was 10.3 ± 0.2 years. No preoperative demographic differences were found between groups. The reoperation group showed more high-grade cartilage defects on the acetabulum and femoral head (33% vs 8%, P = .004; 29% vs 7%, P = .007). A bimodal distribution of time to reoperation was evidenced independent of the secondary surgery performed. Among the reoperation-free survivors, MCID and PASS achievement was as follows: HOS-ADL (69.1%, 62.1%), HOS-SS (69.9%, 74.4%), mHHS (73.3%, 58.1%), iHOT-12 (n/a, 63.8%), and VAS-Pain (80.2%, 62.6%).

CONCLUSIONS

Patients requiring reoperation following primary hip arthroscopy for FAIS demonstrated more severe cartilage defects and a bimodal distribution of time to reoperation.

LEVEL OF EVIDENCE

Level III, retrospective comparative case series.

Patients Aged 40 Years and Older Demonstrate Durable and Comparable Results to Patients Aged Less Than 40 Years After Primary Hip Arthroscopy for Femoroacetabular Impingement Syndrome: A Propensity Matched Study at Minimum 10-Year Follow-Up

PURPOSE

The purpose of the present study was to compare clinical outcomes and rates of secondary surgery, including revision hip arthroscopy and conversion to total hip arthroplasty (THA), after primary hip arthroscopy for femoroacetabular impingement syndrome (FAIS) in patients ≥40 years of age at minimum 10-year follow-up compared with a propensity-matched control group of patients <40 years.

METHODS

A retrospective cohort study was performed for patients who underwent primary hip arthroscopy for FAIS between January 2012 and February 2013. Patients ≥40 years old were propensity matched in a 1:1 ratio by sex and body mass index to patients <40 years old. Patient-reported outcomes (PROs) including Hip Outcome Score for Activities of Daily Living and Sports-Specific subscales, modified Harris Hip, International Hip Outcome Tool-12, and Visual Analog Scale for Pain and Satisfaction were collected. Rates of minimal clinically important difference (MCID) and patient-acceptable symptomatic state (PASS) achievement at 10 years were evaluated and compared between groups. Rates of secondary surgery including revision hip arthroscopy and conversion to THA were evaluated. Gross survivorship between cohorts was evaluated using a Kaplan-Meier curve.

RESULTS

Fifty-three patients aged ≥40 (age 48.3 ± 5.8 years) were successfully matched to 53 patients aged <40 (age: 28.9 ± 7.2, <0.001). There were no other preoperative group differences regarding patient demographics, characteristics, or radiographic findings. Both groups demonstrated significant improvement regarding all PROs at a minimum of 10 years' follow-up (P < .001 for all). No significant difference was noted between cohorts regarding any delta (preoperative to 10-year postoperative) scores (P > .05 for all). High rates of MCID and PASS achievement were achieved in both cohorts, with no significant differences in any PRO measure (P > .05 for all). No significant differences in rates of complications (age ≥40: 2.0%, age <40: 7.7%, P = .363), rates of revision (age ≥40: 7.5%, age <40: 9.4%, P = .999), or conversion to THA (age ≥40: 13.2%, age <40: 3.8%, P = .161) were identified. On Kaplan-Meier analysis, no significant difference (P = .321) was demonstrated in overall gross survivorship between cohorts.

CONCLUSION

Patients with age ≥40 with FAIS undergoing primary hip arthroscopy demonstrated durable and comparable 10-year PRO and rates of MCID and PASS achievement compared with a propensity-matched cohort of age <40 counterparts.

LEVEL OF EVIDENCE

Level III, retrospective comparative prognostic trial.

Hip Arthroscopic Surgery With Chondrolabral Refixation, Osteochondroplasty, and Routine Capsular Closure for Femoroacetabular Impingement Syndrome: Clinical Outcomes at a Minimum 10-Year Follow-up

BACKGROUND

Hip arthroscopic surgery for femoroacetabular impingement syndrome (FAIS) has proven to be an effective surgical intervention, with high rates of return to sport and work as well as favorable outcomes at short- and midterm follow-up. However, limited data exist on outcomes at long-term follow-up.

PURPOSE

To evaluate patient-reported outcomes (PROs) at a minimum 10-year follow-up after primary hip arthroscopic surgery including labral repair, femoral osteochondroplasty, acetabular osteochondroplasty, and capsular closure for FAIS.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients who underwent primary hip arthroscopic surgery for FAIS between June 2012 and January 2013 were identified. PROs were collected preoperatively and at a minimum of 10 years postoperatively, including the Hip Outcome Score-Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sports Subscale (HOS-SS), modified Harris Hip Score (mHHS), International Hip Outcome Tool-12 (iHOT-12), and visual analog scale (VAS) for pain and satisfaction. Unique minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) thresholds were calculated, and their rates of achievement were analyzed. An alpha level of <.05 was used to determine statistical significance.

RESULTS

A total of 94 patients (55 female; mean age, 34.3 ± 12.4 years) were analyzed with a mean follow-up of 10.1 ± 0.3 years (range, 10.0-10.7 years). Patients demonstrated significant 10-year improvement across all PRO measures (P < .001). MCID and PASS thresholds were calculated as follows: HOS-ADL (10.4 and 85.3, respectively), HOS-SS (14.6 and 60.2, respectively), mHHS (8.8 and 76.0, respectively), VAS pain (14.6 and 27.5, respectively), and iHOT-12 (PASS: 71.4). The majority of patients achieved the MCID and PASS for each PRO measure: HOS-ADL (73.4% and 70.9%, respectively), HOS-SS (78.5% and 77.2%, respectively), mHHS (81.0% and 70.9%, respectively), VAS pain (88.6% and 70.9%, respectively), and iHOT-12 (PASS: 73.4%). Overall, 9 patients (9.6%) underwent subsequent revision hip arthroscopic surgery at a mean 4.9 ± 3.7 years (range, 1.1-10.1 years) postoperatively, and 6 patients (6.4%) underwent conversion to total hip arthroplasty at a mean 4.1 ± 3.1 years (range, 0.9-9.3 years) postoperatively.

CONCLUSION

Patients who underwent primary hip arthroscopic surgery for FAIS utilizing contemporary methods of labral repair, acetabular and/or femoral osteochondroplasty, and capsular closure commonly experienced sustained clinical improvement and reported high levels of satisfaction at a minimum 10-year follow-up with low rates of reoperation.

Functional Outcome Scores and Conversion to Total Hip Arthroplasty After Hip Arthroscopy for Femoroacetabular Impingement Syndrome in Patients With Tönnis Grade 1 Versus Grade 0 Arthritis: A Propensity-Matched Study at Minimum 10-Year Follow-up

BACKGROUND

Hip arthroscopy has become the mainstay surgical intervention for the treatment of femoroacetabular impingement syndrome (FAIS). However, postoperative outcomes and rates of secondary surgery are mixed in patients with differing levels of preoperative osteoarthritis (OA). Furthermore, there is a paucity of literature comparing patients with and without OA at long-term follow-up.

PURPOSE

To compare outcomes and rates of secondary surgery at minimum 10-year follow-up, including revision hip arthroscopy and conversion to total hip arthroplasty (THA), in patients with Tönnis grade 1 undergoing hip arthroscopy for FAIS compared with a propensity-matched control group of patients with Tönnis grade 0.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who underwent primary hip arthroscopy for FAIS between January 2012 and February 2013 were identified. Patients with Tönnis grade 1 were propensity matched in a 1:2 ratio by age, sex, and body mass index (BMI) to patients with Tönnis grade 0. Patient-reported outcomes (PROs) were collected at varying timepoints including preoperatively and 1, 2, 5, and 10 years postoperatively and compared between the 2 cohorts. Rates of minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) achievement at 10 years were evaluated and compared between groups. Rates of secondary surgery including revision hip arthroscopy and conversion to total hip arthroplasty (THA) were evaluated. Gross survivorship between cohorts was evaluated using a Kaplan-Meier gross survivorship curve. A subanalysis was performed comparing patients with Tönnis grade 1 who converted to THA and those who did not.

RESULTS

A total of 31 patients with Tönnis grade 1 (age, 42.6 ± 9.0 years; BMI, 28.0 ± 6.3) were successfully matched to 62 patients with Tönnis grade 0 (age, 42.1 ± 8.5, P = .805; BMI, 26.1 ± 3.9, P = .117). Both the Tönnis grade 1 and Tönnis grade 0 groups demonstrated significant improvements regarding all PROs at minimum 10 years (P < .05 for all), except for the Hip Outcome Score Activities of Daily Living subscale (HOS-ADL) (P = .066) in the Tönnis grade 1 cohort. No significant difference (P > .05 for all) was noted between cohorts regarding any 10-year PRO. When the authors evaluated comparisons between preoperative and 1-, 2-, 5-, and 10-year PRO measures, significant differences were noted between cohorts regarding 2-year HOS-ADL (P = .021), Hip Outcome Score Sports-Specific subscale (P = .016), and modified Harris Hip Score (P = .026); otherwise, differences did not reach significance. High rates of 10-year MCID and PASS achievement were seen, with no significant differences between groups. Patients with Tönnis grade 1 had significantly higher rates of conversion to THA compared with patients who had Tönnis grade 0 (25.8% vs 4.8%; P = .006). Patients with Tönnis grade 1 had significantly lower gross survivorship compared with those who had Tönnis grade 0 (71.0% vs 85.5%, respectively; P = .04).

CONCLUSION

Hip arthroscopy confers comparable postoperative clinical improvements to patients who have FAIS with and without mild OA; however, the benefits among patients with mild OA may be less durable. Patients with Tönnis grade 1 had significantly higher conversion to THA and reduced gross survivorship compared with patients with no evidence of preoperative OA, suggesting that patients with evidence of OA may need to be cautioned on the higher rate of conversion surgery.

Timing From Symptom Onset to Hip Arthroscopy Does Not Affect Patient-Reported Outcome Measures for the Treatment of Femoroacetabular Impingement in Adolescent Patients

PURPOSE

To evaluate symptom duration and its relationship to patient-reported outcomes (PROs) and survivorship after hip arthroscopy in adolescents.

METHODS

Patients ≤18 at time of primary hip arthroscopy for femoroacetabular impingement (FAI) between January 2011 and September 2018 were included. Exclusion criteria consisted of history of previous ipsilateral hip surgery, presence of osteoarthritis or dysplasia on preoperative radiographs, previous hip fracture, or history of slipped capital femoral epiphysis or Legg-Calve-Perthes disease. Minimum 2-year PROs (modified Harris Hip Score, Hip Outcome Score [HOS]-Activities of Daily Living, HOS-Sport Scale, Short Forms 12 [SF-12]), minimum clinically significant difference (MCID) and patient-acceptable symptom state (PASS) rates, and revision surgery rates were compared based on symptom duration.

RESULTS

Two-year minimal follow-up was obtained for 111 patients (134 hips) (80%), including 74 females and 37 males with a mean age of 16.4 ± 1.1 (range 13.0-18.0). The mean symptom duration was 17.2 ± 15.2 months (range 43 days to 6.0 years). Ten patients (11 hips), 6 females (7 hips) and 4 males, required revision surgery at an average of 2.3 ± 1.0 years (range 0.9-4.3 years). At a mean follow-up of 4.8 ± 2.2 years (range 2-10 years), there were statistically significant improvements in all PROs (P < .05 for all). Symptom duration showed no significant correlation to post-operative scores (correlation coefficient range -0.162 to -0.078, P > .05 for all). Symptom duration ≤12 months versus >12 months or as a continuous variable was not a predictor for requiring revision surgery or achieving MCID/PASS (95% confidence interval crosses 1 for all).

CONCLUSIONS

In an adolescent cohort of symptomatic FAI patients who underwent hip arthroscopy, there is no difference in PRO measures when analyzing symptom duration by arbitrary time intervals or as a continuous variable.

LEVEL OF EVIDENCE

Level IV, case series.

Workers' Compensation Patients Undergoing Hip Arthroscopy for Femoroacetabular Impingement Syndrome Experience Worse Mid-Term Outcomes but Similar Return-to-Work: A Propensity-Matched Analysis at 5-Year Follow-Up

PURPOSE

To investigate mid-term patient-reported outcomes (PROs) and return-to-work for workers' compensation (WC) patients undergoing primary hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS) versus propensity-matched, non-WC controls and to determine whether achievement rates of minimal clinically important difference (MCID) and patient-acceptable symptom state (PASS) differ between these populations.

METHODS

A retrospective cohort study was conducted on WC patients who underwent primary HA for FAIS from 2012 to 2017. WC and non-WC patients were propensity matched on a 1:4 basis by sex, age, and body mass index (BMI). PROs were compared preoperatively and at 5 years postoperatively, employing the Hip Outcome Score Activities of Daily Living (HOS-ADL) and Sports-Specific (HOS-SS) subscales, modified Harris Hip Score (mHHS), 12-item international Hip Outcome Tool (iHOT-12), and visual analog scales (VAS) for pain and satisfaction. MCID and PASS were calculated using published thresholds for these measures. Preoperative and postoperative radiographs and the presence and timing of return to unrestricted work were evaluated.

RESULTS

Forty-three WC patients were successfully matched to 172 non-WC controls and followed for 64.2 ± 7.7 months. WC patients demonstrated lower preoperative scores for all measures (P ≤ .031) and worse HOS-ADL, HOS-SS, and VAS pain scores at 5-year follow-up (P ≤ .021). There were no differences in MCID achievement rates or magnitude of change between preoperative and 5-year postoperative PROs (P ≥ .093); however, WC patients achieved PASS at lower rates for HOS-ADL and HOS-SS (P ≤ .009). 76.7% of WC and 84.3% of non-WC patients returned to work without restrictions (P = .302) at 7.4 ± 4.4 versus 5.0 ± 3.8 months, respectively (P < .001).

CONCLUSIONS

WC patients undergoing HA for FAIS report worse preoperative pain and function than non-WC patients and experience worse pain, function, and PASS achievement at 5-year follow-up. However, they demonstrate similar MCID achievement and magnitude improvement between preoperative and 5-year postoperative PROs, and return to work without restrictions at a similar rate to non-WC patients, although they may take longer to do so.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Editorial Commentary: The Hip Arthroscopy Volume-to-Competency Learning Curve Debate Is Complicated: Learning When "Enough Is Enough" Is a Lifetime Discipline

As hip arthroscopy use grows, so does resident and fellow exposure, providing more "hands-on" learning opportunities. Nevertheless, hip arthroscopy is technically challenging, particularly noting that improved patient-reported outcomes and survivorship are reported after labral repair or reconstruction (vs debridement) as well as routine capsular closure. Undoubtedly a requisite number of cases is required to reach the saturation point of the "learning curve." A recent review shows that traction time, complication rates, and reoperation rates decrease with increasing case volumes, but there is a wide range of cases reported after which the learning curve "plateaus," ranging from 30 to 520 cases. A large database study shows that hip arthroscopy readmissions and complications are significantly lower in high-volume centers. However, large database studies may include biases requiring attention. First, the rates are relatively low across the entire cohort. Second, more younger patients were treated in the greater-volume centers, which may contribute to the difference in outcomes observed. Finally, older patients (often >50 years old) with concomitant osteoarthritis are also associated with greater complication, readmission, and reoperation rates. Such patients may not be selected as candidates for hip arthroscopy by greater-volume surgeons. The hip arthroscopy volume to competency learning curve debate is complicated. Learning when "enough is enough" is a lifetime discipline.

Hypermobile Patients With Femoroacetabular Impingement Syndrome Can Be Effectively Treated Utilizing Hip Arthroscopy With Periportal Capsulotomy Closure: A Matched Cohort Analysis Compared to Patients Without Joint Hypermobility

PURPOSE

To assess the 2-year outcomes of arthroscopic treatment with periportal capsulotomy closure for femoroacetabular impingement syndrome (FAIS) in patients with generalized ligamentous laxity (GLL).

METHODS

A retrospective analysis was performed from a prospectively collected database of FAIS patients undergoing hip arthroscopy. FAIS patients with GLL were identified as having Beighton score ≥4. FAIS patients with GLL were treated with arthroscopic labral repair, osteochondroplasty, via periportal capsulotomy with subsequent capsular closure. These patients were matched by age, sex, and body mass index (BMI) with a cohort of FAIS patients without GLL who underwent the same procedure via periportal capsulotomy without capsular closure. Preoperatively, and 2 years postoperatively, patients completed patient-reported outcomes (PRO) scores, including the Hip Disability and Osteoarthritis Outcome Score (HOOS), 12-item Short-Form survey (SF-12) and the visual analog scale (VAS).

RESULTS

Forty patients (5 male, 35 female) with FAIS and GLL were included (age: 29.7 ± 9.0; BMI: 23.3 ± 4.1). FAIS patients with GLL demonstrated similar significant PRO score improvements compared to a matched cohort of FAIS patients without GLL at 2 years after surgery (VAS Pain: (-)2.5 ± 3.0, (-)2.7 ± 2.7; SF-12 PCS: 17.7 ± 14.2, 16.7 ± 15.0; HOOS-Symptoms: 26.3 ± 24.0, 20.6 ± 18.1; HOOS-Pain: 29.8 ± 20.4, 24.4 ± 9.0; HOOS-ADL: 24.9 ± 18.4, 22.0 ± 19.9; HOOS-Sports: 43.6 ± 26.1, 33.1 ± 29.8; and HOOS-QOL: 44.2 ± 27.6, 41.7 ± 27.1, respectively). Both cohorts achieved minimal clinically important differences (MCID) for each HOOS subscore at equivalent high rates (70-88%).

CONCLUSIONS

Patients with GLL in the setting of FAIS can be effectively treated with arthroscopy via periportal capsulotomy and capsular closure. These patients demonstrate significant improvements in PRO scores at 2 years, similar to normal laxity FAIS patients undergoing arthroscopic treatment via periportal capsulotomy without capsular closure.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic trial.

Effect of Differing Orientation and Magnitude of Femoral Torsion on Outcomes and Achievement of the MCID and PASS at 5 Years After Hip Arthroscopy for Femoroacetabular Impingement Syndrome

BACKGROUND

Femoral torsion measurements and outcomes are variable throughout the literature and have focused on short-term follow-up. However, there is a paucity of literature investigating clinically meaningful outcomes at midterm follow-up after hip arthroscopy for femoroacetabular impingement syndrome (FAIS).

PURPOSE

To quantify femoral version using computed tomography imaging in patients with FAIS and to explore the relationship between version abnormalities and 5-year outcomes after hip arthroscopy.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who underwent primary hip arthroscopy for FAIS between January 2012 and November 2017 were identified. Patients were included if they had 5-year follow-up with completion of ≥1 patient-reported outcome (PRO) scores and excluded if they had Tönnis grade >1, revision hip surgery, a concomitant hip procedure, a developmental disorder, or a lateral center-edge angle <20°. Torsion groups were defined as severe retrotorsion (<0°), moderate retrotorsion (0.1°-5°), normal torsion (5.1°-20°), moderate antetorsion (20.1°-25°), and severe antetorsion (>25.1°) based on computed tomography measurements. Patient characteristics were analyzed among the torsion cohorts, as were preoperative and 5-year PROs: Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sports Subscale, modified Harris Hip Score, international Hip Outcome Tool, visual analog scale for pain, and visual analog scale for satisfaction. Achievement rates of cohort-specific thresholds for the minimal clinically important difference and Patient Acceptable Symptom State were calculated and compared among cohorts.

RESULTS

A total of 362 patients (244 female, 118 male; mean ± SD age, 33.1 ± 11.5 years; body mass index, 26.9 ± 17.8) met inclusion/exclusion criteria and were analyzed at a final mean follow-up of 64.3 ± 9.4 months (range, 53.5-115.5 months). Mean femoral torsion was 12.8°± 9.2°. The number of patients within each group was 20 for severe retrotorsion (torsion, -6.3°± 4.9°), 45 for moderate retrotorsion (2.7°± 1.3°), 219 for normal torsion (12.2°± 4.1°), 39 for moderate antetorsion (21.9°± 1.3°), and 39 for severe antetorsion (29.0°± 4.2°). No significant differences in age, body mass index, sex, smoking status, workers' compensation, psychiatric history, back pain, or physical activity were found among the torsional groups. All groups demonstrated significant improvements at 5 years postoperatively (P < .01 for all). All torsion subgroups demonstrated similar pre- to postoperative changes in PROs (P≥ .515) and PRO values at 5-year follow-up (P≥ .098). There were no significant differences in the achievement of the minimal clinically important difference (P≥ .422) or Patient Acceptable Symptom State (P≥ .161) for any of the PROs among the torsion groups.

CONCLUSION

The orientation and severity of femoral torsion at the time of hip arthroscopy for FAIS in this study's cohort did not affect the propensity for clinically meaningful outcome improvement at midterm follow-up.

Editorial Commentary: Hip Arthroscopy in Patients With Early Degeneration Who Receive Intra-Articular Bone Marrow Aspirate Concentrate Can Achieve Outcomes Similar to Nonarthritic Patients

The management of patients with early joint degeneration is challenging. In this setting, biologic interventions, from platelet-rich plasma to bone marrow aspirate concentrate (BMAC) to hyaluronic acid, may be beneficial. Recent research, with 2-year follow-up, shows that patients with early degenerative changes (Tönnis grade 1 or 2) who received intra-articular injection of BMAC after hip arthroscopy procedure had improvements in outcomes similar to nonarthritic patients (Tönnis 0) with symptomatic labral tears who underwent arthroscopy and did not receive BMAC. Although confirmatory investigation using patients with early degenerative changes as a control is required, it is possible that with BMAC, patients with early degenerative changes of their hip could achieve functional outcomes similar to patients with nonarthritic hips.

Editorial Commentary: Legacy Patient-Reported Outcome Measures Are Superior to Patient-Reported Outcomes Measurement Information System for Assessing Function After Hip Arthroscopy

Patient-reported outcome measures (PROMs) are critical tools in hip preservation research for evaluating the efficacy of current treatments, as well as identifying risk factors associated with suboptimal outcomes. These measures have been used for quality improvement, for monitoring of health plan performance, and even for reimbursement models. Over the past 2 decades, legacy hip outcome scores have been developed that are patient-centric and evaluate hip-specific function after surgery. There has been a recent trend in using the Patient-Reported Outcomes Measurement Information System (PROMIS), a tool developed by the National Institutes of Health for evaluating PROMs, in the field of hip arthroscopy. However, on the basis of the evidence in the literature, it is unlikely that PROMIS is superior to legacy PROMs regarding evaluation of hip function, nor is it as responsive to quantifying meaningful changes in function that are important to patients. As such, clinicians and researchers alike should likely continue using legacy PROMs to evaluate patients' functional outcomes after hip arthroscopy while continuing to explore the clinical applications of other PROMIS domains.

Patients With Low-Grade Lumbosacral Transitional Vertebrae Demonstrate No Difference in Achievement of Clinical Thresholds After Hip Arthroscopy for Femoroacetabular Impingement Syndrome

PURPOSE

To compare clinical outcomes at 2 years following primary hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS) between patients with and without low-grade lumbosacral transitional vertebra (LSTV).

METHODS

We performed a retrospective matched-cohort analysis of patients who underwent primary HA for FAIS from 2011 to 2018 with minimum 2-year follow-up. LSTV was graded on preoperative radiographs using the Castellvi classification. Patients with grades I and II LSTV were matched 1:1 with controls on age, sex, and body mass index. Radiographic markers of FAIS morphology were measured. Pre- to postoperative improvement in the modified Harris Hip Score (mHHS) and Non-Arthritic Hip Score (NAHS) as well as 2-year achievement rates for the minimum clinically-important difference, substantial clinical benefit, and patient acceptable symptom state were compared between patients with versus without LSTV. The Wilcoxon signed-rank test was used for intergroup mean comparisons and the Cochran-Mantel-Haenszel test for categorical variables.

RESULTS

In total, 58 patients with LSTV were matched to 58 controls. Among LSTV patients, 48 were Castellvi type 1 (82.8%) and 32 (55.2%) had bilateral findings. No significant differences were found between groups with respect to radiographic markers of FAIS, including alpha angle (P = .88), lateral center edge angle (P = .42), or crossover sign (P = .71). Although patients with LSTV had greater improvement in NAHS at 2-year follow-up compared with control patients (P = .04), there were no significant differences in modified Harris Hip Score improvement (P = .31) or achievement of the minimum clinically-important difference (P = .73), substantial clinical benefit (P = .61), or patient acceptable symptom state (P = .16).

CONCLUSIONS

Patients with low-grade LSTV had greater 2-year improvement in NAHS than controls, whereas no significant differences were observed in achievement of clinical thresholds at 2-year follow-up. There were no differences between groups with respect to any measured radiographic markers of FAIS morphology. Importantly, the findings of this study are underpowered and should be viewed with caution in the greater context of the LSTV literature.

LEVEL OF EVIDENCE

III; retrospective comparative study.

Patient-Reported Outcomes Improve at 2-Year Minimum Follow-Up After Hip Arthroscopy for Femoroacetabular Impingement Syndrome: A Systematic Review

PURPOSE

To provide an updated review of recent literature on postoperative outcomes following hip arthroscopy for femoroacetabular impingement syndrome (FAIS), focusing on larger-population studies with a minimum 2-year follow-up published within the last 5 years.

METHODS

A literature search of the PubMed, Ovid Medline, Web of Science, and Cochrane databases was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Articles were screened for clinical studies published from 2017 to 2022 with greater than 100 patients and minimum 2-year follow-up. Exclusion criteria included failure to report postoperative patient-reported outcomes (PROs), no preoperative radiographic measurements, and surgery for pathology other than FAIS. Data collection included study characteristics, patient demographics, radiographic findings, intraoperative findings, procedures performed, postoperative PROs, and subsequent surgeries.

RESULTS

Nine studies met inclusion criteria. Mean or median patient ages ranged from 32.3 to 41 years, with 4 studies reporting on greater than 50% female patients. Mean preoperative lateral center edge angles and alpha angles ranged from 30.2° to 37° and from 56.2° to 71°, respectively. Labral repairs (range 69.7%-100%) were performed more commonly than debridements (range 0%-26.3%). All studies demonstrated improved PROs at most recent follow-up. Seven studies reported mean or median modified Harris Hip Scores, with preoperative and postoperative values that ranged from 53.1 to 80 and from 67.4 to 100, respectively. Revision hip arthroscopies and conversions to hip arthroplasty ranged from 0.8% to 11.6% and from 0% to 34%, respectively.

CONCLUSIONS

All included studies found improvements in PROs after hip arthroscopy for FAIS at a minimum of 2-year follow-up. Conversion to total hip arthroplasty is most common in older patients at minimum 10-year follow-up.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I through IV studies.

Hip Arthroscopy in the Presence of Advanced Osteoarthritis Results in 57% Survivorship, With 78% Survivor Satisfaction, at 10 Years. A Matched-Control Study

PURPOSE

To (1) determine the 10-year survivorship (avoidance of total hip arthroplasty, THA) for patients with advanced osteoarthritis (OA) undergoing hip arthroscopy for femoroacetabular impingement, and (2) compare survivorship and patient-reported outcomes (PROs) with a matched-control group without OA.

METHODS

Advanced OA hips (Tönnis ≥2) were matched in a 1:1 ratio (age ± 5 years, sex) to hips with preoperative Tönnis grade ≤1. Exclusion criteria was dysplasia, age <18 years, previous hip conditions/surgeries, and bilaterally operated patients with OA on one side only. Survival was estimated by Kaplan-Meier analysis for levels of sex, age groups and Tönnis. Cox proportional hazards model estimated hazard ratios (HR) of undergoing THA conversion. Where THA was avoided, outcomes and proportion of cases achieving patient acceptable symptomatic state was determined RESULTS: 53 OA hips were matched with 53 control hips. Survival distributions were significantly different for: (1) Group: OA 57.1%, control 87.0% (P = .001); (2) Tönnis grade: Tönnis 0, 89.2%; Tönnis 1, 77.8%; Tönnis 2, 67.6%; Tönnis 3, 25.0% (P < .001); and (3) age: (OA: 75.0% vs 44.8%, control: 100%, vs 75.0%, for <35 and >35 years respectively) (P = .002). Conversion to THA was greater for increasing Tönnis: HR 1.9 (P = .450), 3.5 (P = .032), and 11.0 (P < .001) for Tönnis 1, 2, and 3 respectively, relative to no OA (Tönnis 0) and >35 years: HR 4.3 (95% confidence interval 1.6-11.3, P = .003). Patient acceptable symptomatic state achievement was similar for both groups (78% OA vs 91% control, P = .167). modified Harris Hip Score and Short Form-36 significantly improved within both groups from baseline to 10 years CONCLUSIONS: Arthroscopic correction of femoroacetabular impingement, in the presence of advanced OA results in 57% survivorship at 10 years (68% Tönnis 2, 25% Tönnis 3). Where THA was avoided, 78% considered their 10-year post-HA state to be satisfactory, with patient-reported outcomes similar to a matched non-OA cohort. Tönnis 2 in particular should be considered for arthroscopic hip preservation to avoid the need to prematurely replace the hip joint.

LEVEL OF EVIDENCE

IV, case series.

Patients Undergoing Primary Hip Arthroscopy Report Favorable Outcomes at Minimum 10 Year Follow-Up: A Systematic Review

PURPOSE

(1) To evaluate minimum 10-year PROs (patient-reported outcomes) and survivorship after primary hip arthroscopy and (2) to identify predictors of failure for secondary arthroscopy and conversion to total hip arthroplasty (THA).

METHODS

A systematic review of the literature was conducted with the following key words: "hip arthroscopy," "long-term," "outcomes," "ten-year," "survivorship," "10-year," "15-year," "fifteen-year," 20-year," "twenty-year," and "femoroacetabular impingement" in PubMed and Embase in March 2022 using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Level I to Level IV evidence was included and reported on minimum 10-year outcomes or greater after primary hip arthroscopy. Long-term studies were defined as minimum 10-year follow-up in accordance with established standards in the literature. Case reports, review articles, technique articles, and opinion articles were excluded. Articles not in English were excluded. Title, author, publication date, study design, demographic, number of hips, follow-up time, study period, indications for hip arthroscopy, PROs, predictors of failure for THA, and rates of secondary surgeries were recorded. Survivorship was defined as a nonconversion to THA. P < .05 was defined as statistical significance.

RESULTS

Twelve studies met the inclusion criteria. In total, 4 studies were Level III, and 8 studies were Level IV. A total of 1,344 hips were included, and follow-up ranged from 10 to 20 years. Femoroacetabular impingement syndrome was the most common indication for hip arthroscopy. Ten of the 12 studies reported on PROs, and 8 studies reported significant improvement after hip arthroscopy at long-term follow-up. The remaining 2 studies reported favorable outcomes that satisfied clinical benefit thresholds at minimum 10-year follow-up. Five studies reported clinical benefit where each patient cohort achieved 80% minimal clinically important difference and 75% patient acceptable symptomatic state for at least one PRO. Rates of secondary arthroscopy ranged from 4.5% to 24%, and rates of conversion to THA varied from 0% to 44.1%. Older age and chondral damage were the most commonly cited predictors for conversion to THA.

CONCLUSIONS

At long-term follow-up, patients who underwent primary hip arthroscopy demonstrated favorable outcomes and variable rates of secondary surgeries. Patients undergoing hip arthroscopy within the last 20 years with Tönnis grade <1 and labral repair experienced greater than 90% survivorship. Chondral damage and older age were the most cited predictors for conversion to THA.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III and Level IV studies.

Hip arthroscopy for femoroacetabular impingement is associated with significant improvement in early patient reported outcomes: analysis of 4963 cases from the UK non-arthroplasty registry (NAHR) dataset

PURPOSE

Results from recent randomised controlled trials demonstrate the superiority of surgery over physiotherapy in patients with femoroacetabular impingement (FAI) of the hip in early follow-up. However, there is paucity of evidence regarding which factors influence outcomes of FAI surgery, particularly notable is the lack of information on the effect of impingement subtype (cam or pincer or mixed) on patient reported outcomes measures (PROMs). This study aims to evaluate the early outcomes of hip arthroscopy for FAI, and their determinants.

METHODS

This is a retrospective analysis of prospectively collected data from the UK Non-Arthroplasty Hip Registry (NAHR) of patients undergoing arthroscopic intervention for FAI between 2012 and 2019. The null hypothesis was that there is no difference in PROMs, based on morphological subtype of FAI treated or patient characteristics, at each follow-up timepoint. The outcome measures used for the study were the iHOT-12 score and the EQ5D Index and VAS 6- and 12-month follow-up.

RESULTS

A cohort of 4963 patients who underwent arthroscopic treatment of FAI were identified on the NAHR database. For all FAI pathology groups, there was significant improvement from pre-operative PROMs when compared to those at 6 and 12 months. Overall, two-thirds of patients achieved the minimum clinically important difference (MCID), and almost half achieved substantial clinical benefit (SCB) for iHOT-12 by 12 months. Pre-operatively, and at 12-month follow-up, iHOT-12 scores were significantly poorer in the pincer group compared to the cam and mixed pathology groups (p < 0.01). Multivariable analysis revealed PROMS improvement in the setting of a higher-grade cartilage lesion.

CONCLUSION

This registry study demonstrates that hip arthroscopy is an effective surgical treatment for patients with symptomatic FAI and results in a statistically significant improvement in PROMs which are maintained through 12 months follow-up.

LEVEL OF EVIDENCE

III.

Hip Arthroscopy With Bone Marrow Aspirate Injection for Patients With Symptomatic Labral Tears and Early Degenerative Changes Shows Similar Improvement Compared With Patients Undergoing Hip Arthroscopy With Symptomatic Labral Tears Without Arthritis

PURPOSE

To define the clinical effect of intra-articular injection of iliac crest-derived bone marrow aspirate concentrate (BMAC) at the time of hip arthroscopy in patients with symptomatic labral tears and early radiographic degenerative changes.

METHODS

A retrospective review of a prospectively collected hip registry database was performed. Patients with symptomatic labral tears and Tönnis grade 1 or 2 degenerative changes who underwent labrum-preserving hip arthroscopy with BMAC injection were included and were matched with patients who underwent hip arthroscopy without BMAC injection. Patient-reported outcomes (PROs) collected preoperatively and up to 2 years postoperatively included the modified Harris Hip Score, Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sport, and International Hip Outcome Tool 33 score. Clinical relevance was measured with the minimal clinically important difference, patient acceptable symptom state, and substantial clinical benefit for each outcome score.

RESULTS

A total of 35 patients underwent labrum-preserving hip arthroscopy with BMAC injection and were matched with 35 control patients. There were no differences in demographic characteristics between the groups (P > .05). The BMAC group consisted of 22 patients (62.9%) with Tönnis grade 1 changes and 13 (37.1%) with Tönnis grade 2 changes, whereas all 35 control patients had Tönnis grade 0 hips. All PROs were significantly improved in both groups at 2 years, with no difference in improvement. The rate of failure requiring conversion to total hip arthroplasty was 14.3% (mean, 1.6 years postoperatively) in the BMAC group and 5.7% (mean, 7 years postoperatively) in the control group (P = .09). The difference in the frequency of patients achieving the minimal clinically important difference, patient acceptable symptom state, and substantial clinical benefit was not statistically significant between cohorts.

CONCLUSIONS

In a challenging group of patients with symptomatic labral tears and early radiographic degenerative changes, hip arthroscopy with BMAC injection results in statistically and clinically significant improvement in PROs comparable to a group of patients with nonarthritic hips undergoing hip arthroscopy at short-term follow-up.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic trial.

Improvement in pain and patient-related outcome measures following hip arthroscopy in patients with femoroacetabular impingement syndrome and concomitant generalized ligamentous laxity: a systematic review

PURPOSE

Within orthopaedic sports medicine, concomitant ligamentous laxity is often found to be a negative prognostic factor for post-operative outcomes following various procedures. The effect of ligamentous laxity on outcomes following hip arthroscopy remains infrequently reported. Therefore, the purpose of this study is to report on the outcomes of hip arthroscopy for the treatment of femoroacetabular impingement syndrome (FAIS) with concomitant generalized ligamentous laxity (GLL).

METHODS

A systematic search was performed in Medline, EMBASE, CENTRAL, and SPORTDiscus (from inception to April 2021) for studies reporting outcomes following hip arthroscopy for symptomatic FAIS in patients with concomitant GLL.

RESULTS

Six studies representing 213 patients and 231 hips were included. Outcomes of pain and functional scores as measured by VAS, Harris Hip Score, and Hip Disability and Osteoarthritis Outcomes Score were tabulated. A mean improvement of 4.8 on VAS was observed. Improvements of 30.0 on HHS, 33.1 for ssHOS, and 23.9 for ADL-HOS were observed.

CONCLUSION

Hip arthroscopy is an effective method of alleviating pain and improving function with statistically significant improvements in all PROM in patients with concomitant FAIS with GLL.

LEVEL OF EVIDENCE

IV.

PROSPERO REGISTRATION

CRD42021248864.

Criteria for Return to Play After Hip Arthroscopy in the Treatment of Femoroacetabular Impingement: A Systematic Review

BACKGROUND

Femoroacetabular impingement (FAI) is a common pathology in athletes that often requires operative management in the form of hip arthroscopy.

PURPOSE

To systematically review the rates and level of return to play (RTP) and the criteria used for RTP after hip arthroscopy for FAI in athletes.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review of the literature, based on the PRISMA guidelines, was performed using PubMed, Embase, and Scopus databases. Studies reporting outcomes after the use of hip arthroscopy for FAI were included. Outcomes analyzed were RTP rate, RTP level, and criteria used for RTP. Statistical analysis was performed using SPSS software.

RESULTS

Our review found 130 studies, which included 14,069 patients (14,517 hips) and had a mean methodological quality of evidence (MQOE) of 40.4 (range, 5-67). The majority of patients were female (53.7%), the mean patient age was 30.4 years (range, 15-47 years), and the mean follow-up was 29.7 months (range, 6-75 months). A total of 81 studies reported RTP rates, with an overall RTP rate of 85.4% over a mean period of 6.6 months. Additionally, 49 studies reported the rate of RTP at preinjury level as 72.6%. Specific RTP criteria were reported in 97 studies (77.2%), with time being the most commonly reported item, which was reported in 80 studies (69.2%). A total of 45 studies (57.9%) advised RTP at 3 to 6 months after hip arthroscopy.

CONCLUSION

The overall rate of reported RTP was high after hip arthroscopy for FAI. However, more than one-fourth of athletes who returned to sports did not return at their preinjury level. Development of validated rehabilitation criteria for safe return to sports after hip arthroscopy for FAI could potentially improve clinical outcomes while also increasing rates of RTP at preinjury levels.

Extent of Cam Resection Relative to Epiphyseal Line and Its Association With Clinical Outcomes After Arthroscopic Treatment for Femoroacetabular Syndrome

Background:

Inadequate resection of cam lesions can cause inferior outcomes after hip arthroscopy and result in revision surgery for femoroacetabular impingement syndrome (FAIS).

Purpose:

To evaluate the association between postoperative cam lesions measured using the proximal boundaries of resection area (PBRE) relative to the epiphyseal line and 2-year outcomes after hip arthroscopy.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Included were patients with FAIS who had undergone primary hip arthroscopy between 2016 and 2018. The PBRE was calculated by measuring the linear distance from the PBRE to the epiphyseal line, dividing it by the diameter of the femoral head, and multiplying by 100; PBRE measurements were made at the 12-, 1-, and 2-o’clock positions on postoperative hip computed tomography. Within each clockface position, patients were divided into subgroups depending on whether their postoperative PBRE was greater than a half standard deviation above the mean (adequate resection) or less than or equal to a half standard deviation above the mean (inadequate resection). Patient-reported outcomes (PROs; Hip Outcome Score–Activities of Daily Living [HOS-ADL], International Hip Outcome Tool–Short Form [iHOT-12], modified Harris Hip Score [mHHS], and pain visual analog scale [VAS]) and rates of achieving the minimal clinically important difference (MCID) and patient-acceptable symptomatic state (PASS) were compared among the subgroups.

Results:

Included were 80 pairs of hips at 12 o’clock, 81 pairs of hips at 1 o’clock, and 80 pairs of hips at 2 o’clock. All subgroups demonstrated significant improvements in PRO scores at a minimum 2-year follow-up compared with preoperatively. At the 12-o’clock position, the subgroup with adequate resection had significantly superior HOS-ADL ( P = .004), iHOT-12 ( P < .001), and mHHS ( P < .001) scores and were more likely to achieve the MCID for the iHOT-12 score ( P = .035) and the PASS for the HOS-ADL ( P = .003), iHOT-12 ( P = .007), and mHHS ( P < .001) scores compared with the matched subgroup. There were no significant differences in PRO scores or rates of MCID and PASS for the 1- or 2-o’clock groups.

Conclusion:

The epiphyseal line may be a useful and reproducible landmark measurement for cam-type deformity. Patients considered to have inadequate resection at 12 o’clock had lower outcome scores at a minimum 2-year follow-up.

Hip Arthroscopy for the Treatment of Femoroacetabular Impingement Syndrome in Hips With Mild Osteoarthritis (Tönnis Grade 1): A Matched Comparative Cohort Analysis at Minimum 5-Year Follow-up

BACKGROUND

There is a paucity of information in the literature on midterm outcomes from the arthroscopic treatment of femoroacetabular impingement syndrome (FAIS) with concomitant labral treatment in patients with mild osteoarthritis (OA) using modern surgical techniques.

PURPOSE

To compare outcomes of hip arthroscopy for the treatment of FAIS between patients with mild OA (Tönnis grade 1) and patients without OA (Tönnis grade 0) at minimum 5-year follow-up.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients were identified who underwent primary hip arthroscopy for FAIS with routine capsular closure between January 2012 and December 2015. Patients with Tönnis grade 1 were matched 1:3 by age, sex, and body mass index to patients without OA. The Hip Outcome Score-Activities of Daily Living (HOS-ADL), HOS-Sports Subscale (HOS-SS), modified Harris Hip Score, and 12-item International Hip Outcome Tool were collected preoperatively and at 5 years postoperatively and compared between groups using an independent t test. Survivorship rate and percentage achievement of a Patient Acceptable Symptom State (PASS) or minimal clinically important difference (MCID) were compared using a Fisher exact test.

RESULTS

A total of 50 patients (54 hips) with Tönnis grade 1 were matched to 162 patients (162 hips) with Tönnis grade 0. The mean ± SD age and body mass index of the Tönnis grade 1 group were 44.5 ± 9.6 years and 28.5 ± 5.5, respectively. Patient-reported outcome (PRO) scores improved significantly for both groups from presurgery to 5 years postoperatively for all PROs (P≤ .03). There were no significant differences in preoperative PROs between the groups. Patients with Tönnis grade 1 had significantly lower postoperative scores on the HOS-ADL (74.7 ± 22.6 vs 83.0 ± 20.1; P = .04) and HOS-SS (58.8 ± 33.7 vs 71.8 ± 29.3; P = .03) than patients with grade 0. Patients with Tönnis grade 1 also had significantly lower rates of achievement of the MCID (57.1% vs 80.2%; P < .01) and PASS (34.1% vs 53.4%; P = .03) for any PRO when compared with patients with Tönnis grade 0. Gross survivorship was significantly lower for Tönnis grade 1 versus grade 0 (77.8% vs 96.9%; P < .001).

CONCLUSION

Patients with Tönnis grade 1 arthritis experienced significant improvement in PROs after hip arthroscopy for the treatment of FAIS. However, they had significantly lower postoperative HOS-ADL and HOS-SS scores with significantly lower rates of achievement on the MCID and PASS, with a significantly lower gross survivorship rate at a minimum 5 years postoperatively in comparison with those with Tönnis grade 0 changes.

The Presence of Central Acetabular Osteophytes May Negatively Affect the Outcome After Primary Arthroscopic Therapy of Femoroacetabular Impingement Syndrome

PURPOSE

To compare short-term follow-up outcomes after primary arthroscopy in femoroacetabular impingement syndrome (FAIS) patients with untreated central acetabular osteophytes (CAO) to a control group without CAO.

METHODS

A retrospective analysis was performed using data from FAIS patients who had primary arthroscopy between 2017 and 2018. The presence of CAO was confirmed arthroscopically, and there were 2 groups created. The CAO group was 1:1 propensity-score matched to a control group (without CAO) based on age, gender, body mass index (BMI), Tӧnnis grade, symptom duration before surgery, and follow-up time. Patient-reported outcomes (PROs), such as the Hip Outcome Score-Activities of Daily Living (HOS-ADL), International Hip Outcome Tool 12-component form (iHOT-12)，modified Harris Hip Score (mHHS), and visual analog scale (VAS) scores were used to evaluate the level of function included. The minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) were also calculated to determine meaningful outcome improvement. Radiographic measures, performed procedures, complications, and revision surgery were also compared and analyzed for both groups. P values less than .05 were considered statistically significant.

RESULTS

A total of 46 hips with CAO and 46 hips without CAO were propensity matched. At the minimum final follow-up of 2 years, the CAO group had significantly lower HOS-ADL (78.8 vs 85.5; P = .008), iHOT-12 (74.8 vs 79.3; P = .019), and mHHS (78.9 vs 87.2; P = .002) scores, as compared to the CAO group. Furthermore, patients in the CAO group were significantly less likely to achieve the MCID and PASS for the mHHS score (78.3% vs 93.5%; P = .036, 58.7% vs 78.2%; P = .043, respectively). There was no change in the rate of complications (4.3% vs 0%) and revision hip arthroscopy (4.3% vs 2.2%) between the two groups at the final follow-up.

CONCLUSIONS

This study demonstrated that surgically treated FAIS patients with CAO might experience worse short-term, patient-reported outcomes, as compared with propensity-matched patients without CAO.

LEVEL OF EVIDENCE

III, case-control study.

Presence of a Posterior Wall Sign in the Treatment of Femoroacetabular Impingement Syndrome: A Matched Comparative Cohort Analysis at Minimum 2-Year Follow-Up

BACKGROUND

Acetabular retroversion may predispose to more severe femoroacetabular impingement syndrome (FAIS) and early labral damage given impaction of the femoral head-neck junction on the retroverted acetabular rim. The cross-over sign (COS), posterior wall sign (PWS), and ischial spine sign (ISS) are markers of acetabular retroversion (AR) on plain radiographs.

METHODS

Patients who underwent primary hip arthroscopy for FAIS from January 2012 to December 2018 with a positive PWS were matched in a 1:1 ratio by age, gender, and body mass index (BMI) to controls with a negative PWS. Preoperative and postoperative patient-reported outcomes (PROs; HOS-ADL, HOS-SS, mHHS, and iHOT-12) were compared using independent t-tests. Achievement of a Patient Acceptable Symptom State (PASS) or Minimal Clinically Important Difference (MCID) was compared using Fisher's exact test.

RESULTS

Two hundred and seventy five patients with a positive PWS and 275 controls were included in the final analysis. Most patients (64%) were female, with average age, and BMI of 37.6 (SD 8.6) and 25.1 (SD 4.4), respectively. PROs improved significantly for both groups from preoperatively to 2 years postoperatively. There were no statistically significant differences (P ≥ .05) in PROs or achievement of MCID or PASS. On a subgroup analysis, patients with all three positive signs had significantly lower postoperative PROs and lower rates of achievement of MCID and PASS.

CONCLUSION

Patients with an isolated PWS achieve similar outcomes following hip arthroscopy at 2 years. However, patients with a concomitant PWS, ISS, and COS demonstrate less favorable outcomes, suggesting the need for increased perioperative counseling and potential evaluation for planned concurrent or serial open procedures such as periacetabular osteotomy.

Outcomes After Primary Hip Arthroscopy in Athletes Older Than 40 Years Compared With Nonathletes

BACKGROUND

Master athletes (MAs), or athletes older than 40 years, make up a patient population whose outcomes after primary arthroscopic hip surgery are largely unknown.

PURPOSE

To report minimum 2-year outcomes of MAs after primary hip arthroscopy and compare their results to a propensity-matched nonathlete (NA) control group.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected between February 2008 and April 2019 and retrospectively reviewed for all patients who underwent primary hip arthroscopy. Patients were included if they were older than 40 years and had preoperative data for the modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score-Sports Specific Subscale, and visual analog scale score for pain. MAs reported participating in organized sports competition within 1 year before surgery and were propensity matched to a control group of patients who did not report participating in organized sports competition (NAs). Patient characteristics, radiographic and intraoperative findings, surgical procedures performed, and patient-reported outcome measures (PROMs) were reported and compared between the groups. The rates of achieving the minimal clinically important difference and maximum outcome improvement satisfaction threshold were recorded.

RESULTS

A total of 366 hips were eligible; 328 (89.6%) had adequate follow-up data. 328 patients met inclusion criteria but 88 were not included due to the restrictions of the propensity score match ratio. Of these, 80 hips (76 patients) were classified as MAs (mean age, 48.9 ± 6.2 years) and were propensity matched 1:2 to an NA control group. Groups were comparable for baseline demographic and radiographic parameters, intraoperative findings, and procedures performed. MAs had significantly better baseline and minimum 2-year PROM scores (P < .05), higher satisfaction (P = .01), and higher rates of achieving clinically meaningful improvement across all the outcome tools used (P < .05). MAs, when compared with NAs, had lower rates of secondary arthroscopy (0% vs 7.5%, respectively; P = .001) and conversion to total hip arthroplasty (12.5% vs 26.9%, respectively; P = .011).

CONCLUSION

MAs demonstrated favorable outcomes after primary hip arthroscopy. When compared with a propensity score-matched control group of NA patients, MAs demonstrated better preoperative and postoperative PROMs, higher rates of clinically meaningful improvement, and lower rates of secondary arthroscopy and conversion to total hip arthroplasty. Absolute improvements in PROM scores were similar between the groups.

Healing of joint capsule after hip arthroscopy using interportal capsulotomy and capsular closure influences clinical outcomes

Background

Hip arthroscopy for treatment of femoroacetabular impingement (FAI) has developed rapidly and has been shown to significantly decrease pain and improve hip function. However, the relationship between hip capsule characteristics and healing after arthroscopic surgery and changes in patient-reported outcomes scores (PROs) for postoperative pain, function, and symptoms is still uncertain.

Methods

We retrospectively evaluated consecutive patients who were diagnosed with FAI and underwent hip arthroscopy for treatment in our hospital between May 2018 and November 2020. All patients had preoperative MRI and postoperative MRI at least 6 months after arthroscopy. Hip capsular thickness was measured at the proximal, middle, and distal site of the capsule. PROs and PROs at final follow-up were obtained, including visual analog scale (VAS) for pain and modified Harris Hip Score (mHHS).

Results

A total of 194 patients were included in this study. The mean MRI follow-up time was 14.3 (range, 6–37) months, and the mean clinical follow-up time was 26.1 (range, 12–43) months. Postoperative capsular thickness or net change were not correlated with postoperative PROs and VAS (P > .05). Capsular defect was observed in 17 (8.8%) patients. Patients with capsular defect had a relatively higher BMI (P < .05). Patients with capsular defect had a significant lower mHHS and higher VAS compared with patients with continuous capsule (P < .05). Ninety-one percentage of patients with continuous capsule surpassed minimal clinically important difference (MCID) and 80.8% achieved PASS, but only 58.8% of patients with capsular defect surpassed MCID and 47.1% achieved patient acceptable symptom state (PASS).

Conclusions

Postoperative capsular thickness may not have influence on the clinical outcomes of hip arthroscopy for treatment of FAI. Some capsule of patients who underwent arthroscopic interportal capsulotomy and repair could not heal. Postoperative capsular continuity had a great impact on the clinical outcomes of hip arthroscopy for FAI. Patients with higher BMI may be more likely to have capsule failure to heal.

Routine Capsular Closure With Hip Arthroscopic Surgery Results in Superior Outcomes: A Systematic Review and Meta-analysis

BACKGROUND

In hip arthroscopic surgery, capsulotomy is performed to improve visualization and allow instrumentation of the joint. Traditionally, the defect has been left unrepaired; however, increasing evidence suggests that this may contribute to persistent pain and iatrogenic capsular instability. Nevertheless, the clinical benefit of performing routine capsular repair remains controversial.

PURPOSE/HYPOTHESIS

We conducted a systematic review and meta-analysis to investigate the effects of routine capsular closure on patient-reported outcomes (PROs), hypothesizing that superior PROs would be observed with routine capsular closure.

STUDY DESIGN

Meta-analysis and systematic review; Level of evidence, 4.

METHODS

A systematic review and meta-analysis was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The terms "hip,""arthroscopy,""capsule,""capsular,""repair," and "closure" were used to query Ovid MEDLINE, Embase, CENTRAL (Cochrane Central Register of Controlled Trials), CINAHL (Cumulative Index to Nursing and Allied Health Literature), SPORTDiscus, and PubMed. Articles with PROs stratified by capsular management were included. Multivariate mixed-effects metaregression models were implemented with study-level random-effects and fixed-effects moderators for capsular closure versus no repair and after controlling for surgical indication and preoperative PROs. The effect of repair on both the postoperative score and the change in scores was evaluated via the Harris Hip Score (HHS)/modified HHS (mHHS), Hip Outcome Score (HOS)-Activities of Daily Living (ADL), and HOS-Sport Specific Subscale (SSS), with a supplemental analysis of additional outcomes.

RESULTS

Of 432 initial articles, 36 were eligible for analysis, with results for 5132 hip arthroscopic procedures. The capsule was repaired in 3427 arthroscopic procedures and unrepaired in 1705. Capsular repair was associated with significantly higher postoperative HHS/mHHS (2.011; SE, 0.743 [95% CI, 0.554-3.467]; P = .007), HOS-ADL (3.635; SE, 0.873 [95% CI, 1.923-5.346]; P < .001), and HOS-SSS (4.137; SE, 1.205 [95% CI, 1.775-6.499]; P < .001) scores as well as significantly superior improvement on the HHS/mHHS (2.571; SE, 0.878 [95% CI, 0.849-4.292]; P = .003), HOS-ADL (3.315; SE, 1.131 [95% CI, 1.099-5.531]; P = .003), and HOS-SSS (3.605; SE, 1.689 [95% CI, 0.295-6.915]; P = .033).

CONCLUSION

This meta-analysis is the largest to date evaluating the effect of capsular closure on PROs and demonstrates significantly higher mean postoperative scores and significantly superior improvement with repair, while controlling for the effects of preoperative score and surgical indication. The true magnitude of the benefit of capsular repair may be clarified by large prospective randomized studies using PRO measures specifically targeted and validated for hip arthroscopic surgery/preservation.

Variations in postoperative electrolyte concentrations and influential factors in hip arthroscopy

BACKGROUND

Different from arthroscopy in other joints, more perfusion is required for a better access to perform surgical procedures in hip arthroscopic operations. The significant fluid perfused may lead to complications of partial tissue injury and electrolyte imbalance. However, there were few studies on the change of serum electrolyte after hip arthroscopy and the influential factors were still unknown.

METHODS

We evaluated consecutive patients who underwent hip arthroscopy in our hospital between October 2021 and February 2022. Age, sex, and BMI matched patients who underwent arthroscopic anterior cruciate ligament (ACL) reconstruction at the same time were also included as the control group. Preoperative and postoperative serum electrolyte of sodium (Na +), potassium (K +), chloride (Cl-), magnesium (Mg2 +), and carbon dioxide capacity (CO2CP) were analyzed. The correlations between influential factors like perfusion volume, operating time, BMI and hip circumference, and changes in serum electrolyte were also analyzed.

RESULTS

A total of 79 patients were involved in this study, including 49 patients who underwent hip arthroscopy and 30 patients who underwent knee arthroscopy. For hip arthroscopy, decrease of potassium levels was observed in 40.8% of the patients, and postoperative hypokalemia was found in 10.2% patients. There were significant variations in postoperative sodium, magnesium, chloride and carbon dioxide capacity in hip arthroscopy (p < 0.05). No correlations were found between each of the electrolyte concentrations and influential factors like perfusion volume, operating time, BMI, sex and hip circumference. The significant variations were found in chloride and carbon dioxide capacity in knee arthroscopy (p < 0.05).

CONCLUSIONS

Hip arthroscopy would significantly influence postoperative serum electrolyte, and hypokalemia could be a postoperative complication. The correlation between serum electrolyte and fluid perfusion volume is remained to be investigated. We therefor advocate that performing a systematic care of preoperative and postoperative serum electrolyte analysis as perioperative management is necessary.

Outcomes and Survivorship at a Median of 8.9 Years Following Hip Arthroscopy in Adolescents with Femoroacetabular Impingement: A Matched Comparative Study with Adults

BACKGROUND

Because of the unique theoretical surgical risks, including osteonecrosis, acute iatrogenic slipped capital femoral epiphysis, and epiphyseal injury, the optimal treatment strategy for femoroacetabular impingement (FAI) in growing adolescents has yet to be established. The aim of this study was to compare the clinical outcomes of primary arthroscopic treatment of FAI in growing adolescents with a matched adult group.

METHODS

Patients with FAI who underwent arthroscopic treatment with a minimum follow-up of 2 years were included. Patients with previous ipsilateral hip surgery, an Outerbridge grade of ≥3, a preoperative Tönnis grade of ≥2, or evidence of dysplasia (lateral center-edge angle of <25°) were excluded. Eligible patients who were ≤19 years old and whose proximal femoral physis had not yet closed were matched to adult (20 to 40-year-old) counterparts in a 1:1 ratio by sex, body mass index, and time of surgery. For the adolescents, cam resection was performed with a physeal-sparing approach. Outcome scores, including the modified Harris hip score (mHHS), Hip Outcome Score-Activities of Daily Living (HOS-ADL), and HOS-Sports-Specific Subscale (HOS-SSS), were prospectively collected.

RESULTS

Of the 196 eligible adolescents, 157 (80%) were pair-matched to adult controls, with a median postoperative follow-up of 8.9 and 6.6 years, respectively. Fourteen (9%) of the adolescents required revision hip arthroscopy compared with 18 adults (11%) (p = 0.46). No patient in the adolescent group had conversion to a total hip arthroplasty (THA), while 3 in the adult group had a THA (p = 0.25). For adolescents without subsequent hip surgery, the median mHHS improved from 59 preoperatively to 96 postoperatively; the HOS-ADL, from 71 to 98; and the HOS-SSS, from 44 to 94 (p < 0.001), which were significantly higher postoperative scores than those of the matched adults (p < 0.05) despite similar or inferior baseline scores. No complications were found during the office visit or at the final follow-up.

CONCLUSIONS

Hip arthroscopy performed with a physeal-sparing approach for FAI in growing adolescents is safe and effective and yields superior clinical outcomes compared with those in a matched adult group.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Lower Center Edge Angle and Bioipolar Cartilage Lesions Are Associated With Conversion to Hip Arthroplasty Within 2 Years Following Hip Arthroscopy: A Matched Cohort Analysis

PURPOSE

The purpose of this study was to determine whether radiographic parameters, intraoperative findings, patient-reported outcome measures, or intraoperative interventions that were performed differentiate those patients with >2 mm of joint space who convert under two years to total hip arthroplasty (THA) after undergoing hip arthroscopy for femoroacetabular impingement (FAI) when compared to those converting after 2 years.

METHODS

Included in this study were patients who underwent conversion to THA within 2 years of primary hip arthroscopy from a prospectively collected patient registry from 2007 to 2017. Patients who underwent early conversions to arthroplasty were matched 1:1 with patients who converted after 2 years, based upon age and gender. Preoperative outcome scores were collected, including Short Form-12, modified Harris Hip Score, and Hip Outcome Score. Additionally, variables from the preoperative radiographic evaluation, surgical findings, and procedures performed were also compared.

RESULTS

Forty-nine patients were included in the early conversion group and were matched with 49 patients in the later conversion group. Patients with lateral center edge angles of less than 25° were more likely to be in the early failure group [OR: 3.9; 95% CI: 1.01 to 15]. Patients with unipolar chondral defects on either the femoral (P = .128) or acetabular side (P = .656) were not at increased odds for early conversion compared to later conversion; however, those with bipolar chondral lesions at the time of surgery had increased odds of early conversions [OR: 3.3; 95% CI: 1.4 to 8] (P = .01). Neither surgical treatment nor preoperative patient-reported outcome measures were associated with early conversion.

CONCLUSIONS

In patient with >2 mm of joint space, lateral center edge angles of less than 25° and those with bipolar articular cartilage lesions seen at the time of hip arthroscopy are at increased risk for conversion to total hip arthroplasty within two years.

LEVEL OF EVIDENCE

Level III, retrospective comparison study.

Osteochondroplasty Benefits the Pragmatic Patient With Femoroacetabular Impingement: Analysis From the Embedded Prospective Cohort of the Femoroacetabular Impingement RandomiSed Controlled Trial (FIRST)

PURPOSE

To determine whether arthroscopic osteochondroplasty demonstrated effectiveness in a pragmatic femoroacetabular impingement patient population embedded within FIRST (the Femoroacetabular Impingement RandomiSed controlled Trial).

METHODS

All cohort patients were not randomized and were followed prospectively with a follow-up assessment protocol identical to that in FIRST. The primary outcome was hip pain using a 100-point visual analog scale. Secondary outcomes included hip function (Hip Outcome Score, International Hip Outcome Tool-12), health utility (EuroQol 5 Dimensions), and health-related quality of life (Short Form-12) at 12 months, as well as operatively and nonoperatively treated hip complications at 24 months. We performed multivariable regressions to compare these outcomes between 3 groups of patients: (1) those randomized to lavage in FIRST, (2) those randomized to osteochondroplasty in FIRST, and (3) those who received osteochondroplasty as part of the cohort study.

RESULTS

All groups had improvements across all questionnaire outcomes from baseline to 12 months, with no significant differences. There were significantly more reoperations in the lavage trial group compared with those in the embedded cohort (adjusted odds ratio [aOR] 3.08; 95% confidence interval [CI] 1.23-7.73; P = .016). There were significantly more nonoperatively treated hip complications in the lavage trial group and in the osteochondroplasty trial group when compared with those in the embedded cohort (aOR 3.81; 95% CI 1.19-12.17; P = .024 and aOR 4.55; 95% CI 1.43-14.42; P = .010, respectively).

CONCLUSIONS

Hip arthroscopic osteochondroplasty and lavage led to improvement in hip pain, function, and health-related quality of life at 12 months across both randomized controlled trial (RCT) and cohort patients. The pragmatic cohort receiving osteochondroplasty had (1) significantly fewer complications than RCT patients, (2) significantly less reoperations than RCT patients randomized to arthroscopic lavage, and (3) fewer, although nonsignificant, reoperations than RCT osteochondroplasty patients.

LEVEL OF EVIDENCE

II, therapeutic.

Ten-Year Outcomes After Hip Arthroscopy in Patients With Femoroacetabular Impingement and Borderline Dysplasia

BACKGROUND

The role of hip arthroscopy in the treatment of patients with borderline hip dysplasia is controversial and evolving.

PURPOSE

To evaluate outcomes at a minimum 10-year follow-up in patients who underwent hip arthroscopy for femoroacetabular impingement in a hip with borderline dysplasia.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

All hips that underwent labral repair between June 2006 and March 2009 for femoroacetabular impingement with borderline dysplasia were included if they had a lateral center-edge angle of 20° to 25°, had primary hip arthroscopy for the diagnosis of femoroacetabular impingement, and were aged 18 to 70 years. Patients were excluded if they had previous hip surgery, avascular necrosis, or fracture. Kaplan-Meier survivorship was performed, with survivorship defined as avoidance of conversion to total hip arthroplasty (THA).

RESULTS

A total of 45 patients met the inclusion criteria, and 38 were contacted at a minimum 10 years postoperatively (84%; mean ± SD, 12 ± 1.3 years). There were 23 women and 15 men with an average age of 41 ± 9.6 years (range, 25-69). Twenty patients were ≥40 years of age. In this patient cohort, survivorship was 87% at 5 years and 79% at 10 years for conversion to THA. Of the 38 patients included, 9 were converted to THA (24%), and 3 required revision hip arthroscopy (7%). Patient age, Tönnis grade, microfracture of cartilage lesions, and Tönnis angle >15° were associated with conversion to THA. No statistically significant differences were found between those who underwent conversion to THA and those who did not regarding lateral center-edge angle, Sharp angle, or alpha angle. Significant improvements were seen at follow-up of 12 years (range, 10-13) for the modified Harris Hip Score (58 to 83; P = .002), Hip Outcome Score-Activities of Daily Living (70 to 87; P = .003), Hip Outcome Score-Sport (47 to 76; P = .004), and Western Ontario and McMaster Universities Osteoarthritis Index (31 to 10; P = .001). At follow-up, >80% maintained the minimal clinically important difference for the Hip Outcome Score (Activities of Daily Living and Sport) with no differences between patients aged <40 and ≥40 years.

CONCLUSION

Risk factors for conversion to THA after hip arthroscopy in the borderline dysplastic hip included older age, higher Tönnis grades, grade 4 chondral lesions that were microfractures, and Tönnis angle >15°. In those patients who did not convert to THA, improvement in outcome measures was seen at 10 years. Careful patient selection is critical to the success of this procedure.

Defining the Patient Acceptable Symptom State for the HOOS JR and KOOS JR After Primary Total Joint Arthroplasty

BACKGROUND

It is essential to quantify an acceptable outcome after total joint arthroplasty (TJA) in order to understand quality of care. The purpose of this study was to define patient acceptable symptom state (PASS) thresholds for the Knee injury and Osteoarthritis Outcome Score, Joint Replacement (KOOS JR) and the Hip disability and Osteoarthritis Outcome Score, Joint Replacement (HOOS JR) after TJA.

METHODS

A receiver operating characteristic (ROC) curve analysis, leveraging 2-year satisfaction of "moderate improvement" or better as the anchor, was used to establish PASS thresholds among 5,216 patients who underwent primary total hip arthroplasty and 4,036 who underwent primary total knee arthroplasty from 2007 to 2012 with use of an institutional registry. Changes in PASS thresholds were explored by stratifying and recalculating these thresholds by age at the time of surgery (<70 or ≥70 years of age), sex (men or women), body mass index (BMI; <30 or ≥30 kg/m2), and baseline Short Form-36 (SF-36) physical and mental component scores (<50 or ≥50).

RESULTS

The HOOS JR PASS threshold was 76.7 (area under the ROC curve [AUC] = 0.91), which was achieved by 4,334 patients (83.1%). The KOOS JR PASS threshold was 63.7 (AUC = 0.89), which was achieved by 3,461 patients (85.8%). Covariate stratification demonstrated that PASS thresholds were higher in men compared with women, and in those with higher preoperative SF-36 physical and mental scores (≥50) compared with lower SF-36 scores (<50). Results differed between instruments for BMI and age: higher BMI was associated with a lower PASS threshold for the HOOS JR but a higher PASS threshold for the KOOS JR. The HOOS JR PASS threshold was higher in patients who were <70 years of age compared with those who were ≥70 years of age, but was equivalent for the KOOS JR.

CONCLUSIONS

The PASS thresholds for the HOOS JR and KOOS JR at 2 years after TJA were 76.7 and 63.7, respectively. The PASS thresholds were associated with certain preoperative covariates, suggesting that an acceptable symptom state after TJA is influenced by patient-specific factors.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Arthroscopic acetabular labrum suture

It is essential to be aware of the anatomy and biomechanics of the acetabular labrum in order to understand why it should be conserved. Vascularization comes from the capsule and also from the bone. The joint side contains numerous nerve endings, which explains why labral lesions are painful. It is involved in joint stabilization by maintaining a negative pressure inside the joint able to resist distraction. It acts as a seal. There are two main suture techniques: trans- and peri-labral. Translabral suture is better suited to a wide and solid labrum free of degenerative lesions. Both techniques should be known, and may be associated. Results are comparable. It is essential to manage the underlying pathology responsible for the labral lesion. Joint degeneration is associated with poor prognosis. It needs to be recognized and discussed with the patient, to avoid unrealistic expectations.

High prevalence of acetabular rim osteophytes after hip arthroscopy for treatment of FAI

Background

Few studies mentioned acetabular rim osteophytes (ARO) after arthroscopy for femoroacetabular impingement (FAI) in follow-up after primary hip arthroscopy. We found that many patients had postoperative ARO, which may lead to recurrent or secondary pincer-type deformity after primary hip arthroscopy for FAI and postoperative ARO sometimes even led to revision surgery. It is necessary to carry out related research on ARO.

Methods

We respectively evaluated consecutive cases who underwent hip arthroscopy in our hospital between January 2008 and January 2020. Radiographic examination was obtained for all patients preoperatively and postoperatively. Another CT scan was performed at least 6 months after surgery at final follow-up. Preoperative patient-reported outcomes (PROs) and PROs at final follow-up were obtained, including visual analog scale (VAS) for pain and modified Harris Hip Score (mHHS). The volume of ARO was calculated using mimics 21.0 software. According to the material of anchors and whether the anchors were used, patients were divided into absorbable group, non-absorbable group and no anchor group.

Results

A total of 71 patients were finally included in this study. Patients with postoperative ARO had higher VAS at final follow-up (P<0.05). Patients without postoperative ARO had higher mean mHHS at final follow-up (P = 0.08) and higher percentage of passing minimal clinical important difference. The percentage and volume of postoperative ARO was significantly higher in patients who underwent acetabuloplasty and labral repair (P<0.05). The percentage and volume of postoperative ARO in absorbable group were significantly higher than the other groups (P<0.05).

Conclusion

There is a high percentage of ARO after hip arthroscopy for treatment of FAI and patients who have undergone labral repair and acetabuloplasty are more likely to have postoperative ARO. Using of absorbable anchors may increase the possibility and volume of postoperative ARO. Postoperative ARO may predict a worse clinical outcome.

Prolonged Postoperative Opioid Use After Arthroscopic Femoroacetabular Impingement Syndrome Surgery: Predictors and Outcomes at Minimum 2-Year Follow-up

Background:

The association between prolonged postoperative opioid use on outcomes after hip preservation surgery is not known.

Purpose:

To compare minimum 2-year patient-reported outcomes (PROs) between patients who required ≥1 postoperative opioid refill after undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS) versus patients who did not require a refill and to identify preoperative predictors for patients requiring ≥1 postoperative opioid refill.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Data from consecutive patients who underwent arthroscopic surgery for FAIS between January 2012 and January 2017 were analyzed. Multivariate regression analysis was performed to classify patient and radiographic variables as predictive of requiring ≥1 opioid prescription refill after surgery. Patients completed the following PROs preoperatively and at 2-year follow-up: Hip Outcome Score— Activities of Daily Living subscale (HOS-ADL), HOS–Sports Subscale (HOS-SS), modified Harris Hip Score (mHHS), International Hip Outcome Tool (iHOT-12), and 100-point visual analog scale (VAS) for pain and satisfaction. Scores were compared between patients needing additional prescription opioids and those who did not.

Results:

A total of 775 patients, of whom 141 (18.2%) required ≥1 opioid prescription refill, were included in the analysis. Patients requiring opioid refills had significantly lower 2-year postoperative PRO scores compared with patients not requiring refills: HOS-ADL (79.9 ± 20.3 vs 88.7 ± 14.9), HOS-SS (64.6 ± 29.5 vs 78.2 ± 23.7), mHHS (74.2 ± 21.1 vs 83.6 ± 15.9), iHOT-12 (63.6 ± 27.9 vs 74.9 ± 24.8), and VAS satisfaction (73.4 ± 30.3 vs 82.2 ± 24.9), as well as significantly more pain (26.8 ± 23.4 vs 17.9 ± 21.8) (P ≤ .001 for all). Predictors of requiring a postoperative opioid refill included patients with active preoperative opioid use (odds ratio, 3.12 [95% confidence interval, 1.06-9.21]; P = .039) and larger preoperative alpha angles (odds ratio, 1.04 [95% confidence interval, 1.01-1.07]; P = .03).

Conclusion:

Patients requiring ≥1 opioid prescription refill after hip arthroscopy for FAIS had lower preoperative and 2-year PRO scores when compared with patients not requiring refills. Additionally, active opioid use at the time of surgery was found to be predictive of requiring additional opioids for pain management.

Improved Functional Outcome Scores Associated with Greater Reduction in Cam Height Using the Femoroacetabular Impingement Resection Arc During Hip Arthroscopy

PURPOSE

We sought to evaluate the association between postoperative cam lesion measured by the femoroacetabular impingement resection (FAIR) arc and show 2-year patient outcomes following hip arthroscopy.

METHODS

A retrospective review of prospectively gathered data from 2013-2017 was performed. All patients who underwent hip arthroscopy for femoroacetabular impingement resection (FAI) with ≥2-year follow-up were included. Cam FAIR arc measurements were made preoperatively and postoperatively on a 45° Dunn view radiograph. The clinical effect of postoperative cam maximal radial distance (MRD) was assessed using the modified Harris Hip Score (mHHS) and Non-Arthritic Hip Score (NAHS). Patients were divided into subgroups based on relationship to the mean and standard deviations for cam MRD. One half standard deviation above the mean was found to be 3.15 mm.

RESULTS

Sixty-one hips in 59 consecutive patients (age 38.1 ± 13.1; body mass index [BMI]: 25.5 ± 4.3; 36 females) were included. Mean preoperative and postoperative cam maximal radial distances (MRD) were 4.5 ± 1.7 mm and 2.3 ± 1.7 mm (P < .001), respectively. The interclass correlation coefficient was excellent (>.9) for all measurements. There were no differences in age, sex, BMI or preoperative mHHS/NAHS between <3.15 mm and >3.15 mm cam MRD groups (P > .05). Using linear regression, cam MRD was found to be significantly associated with 2-year outcomes for both mHHS (R² = .21, P < .001) and NAHS (R² = .004). Subgroup analysis demonstrated that patients in the cam MRD < 3.15 mm group had significantly higher mHHS (89.7 vs 70.0, P < .001) and NAHS scores (90.5 vs 72.9, P < .001) than those in the >3.15 mm group. Additionally, more patients in the <3.15 mm group reached the minimal clinically important difference (95.2% vs 78.9%, P = .048) and were above patient acceptable symptomatic state (95.2% vs 52.6%, P < .001) compared to the >3.15 mm group.

CONCLUSION

Patients with a lower postoperative cam MRD relative to the FAIR arc demonstrated significantly improved outcomes as compared to those with higher postoperative MRD at two-year follow-up.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Hip Arthroscopy Volume and Reoperations in a Large Cross-Sectional Population: High Rate of Subsequent Revision Hip Arthroscopy in Young Patients and Total Hip Arthroplasty in Older Patients

PURPOSE

To report contemporary trends in hip arthroscopy case volume in the United States using a large cross-sectional cohort with accurate laterality tracking for assessment of revision surgery and rates of conversion to total hip arthroplasty (THA).

METHODS

Using Current Procedural Terminology codes, we queried the Mariner PearlDiver dataset for patients who underwent hip arthroscopy from 2010 to 2017. Patient demographics were recorded and subsequent hip arthroscopy procedures and THA conversion within 2 years after surgery were tracked using International Classification of Diseases, Tenth Revision codes to accurately identify laterality. Emergency department and hospital admission within 30 days after surgery were queried.

RESULTS

Of the 53,103 patients undergoing hip arthroscopy procedures, hip arthroscopy case volume increased 2-fold from 2010 to 2014 but remained relatively unchanged from 2014 to 2017. The most common age group undergoing surgery was 40 to 49 years, and female patients represented 70% of cases. Two-year subsequent surgery rate was 19%, with 15.1% undergoing a revision arthroscopy and 3.9% converting to THA. The most common revision arthroscopy procedures were femoroplasty (9.5%), labral repair (8.5%), and acetabuloplasty (4.3%). Younger patients were more likely to undergo revision arthroscopy (18% age 10-19 years; 15% age 20-29 years). Older patients had a significant risk for conversion to THA within 2 years (36% age 60-69 years; 28% age 50-59 years). Female patients also demonstrated a slightly greater rate of conversion to THA (4.1% female, 3.5% male, P <.0001). Patients 20 to 29 years had the greatest risk of emergency department admission (5.4%) and hospital admission (0.8%) within 30 days of surgery.

CONCLUSIONS

The rise in hip arthroscopy procedures may be starting to plateau in the United States. Cross-sectional data also indicate that there is a greater than previously reported rate of revision hip arthroscopy in patients younger than 30 years of age and conversion to THA in patients older than 50 years of age.

LEVEL OF EVIDENCE

III, cross-sectional study.

Surgical Treatment of Femoroacetabular Impingement: Minimum 10-Year Outcome and Risk Factors for Failure

Femoroacetabular impingement (FAI) is a well-known cause of hip pain and dysfunction in young adults. Surgical treatment has been widely popularized during the past decade. However, most reported results have been limited to short-term and intermediate-term follow-up. The long-term success rate and risk factors for failure are largely unknown. This study aimed to report the long-term (minimum, 10 years) clinical outcomes of surgical treatment of FAI and to describe the clinical and radiographic parameters associated with the failure of treatment involving femoroacetabular osteoplasty (FAO) and labral repair.

Hip Joint Kinematic Covariation During Gait Before and 1-Year After Hip Arthroscopic Surgery for Femoroacetabular Impingement Syndrome

The primary aim of this study was to determine if the three-dimensional (3D) hip joint motion coordination during gait changes after arthroscopic surgery for femoroacetabular impingement syndrome (FAIS). Three-dimensional hip joint kinematic data were collected with a 12-camera motion capture system. Five trials of level walking were collected preoperatively (PRE) and at 1-year postoperatively (POST) in 8 patients diagnosed with FAIS and at a single time point in 8 healthy controls. Planar covariation analysis was performed to quantify the 3D hip joint motion coordination strategy during gait. Independent sample's t-test were used to determine differences between the FAIS group at the preoperative time point (PRE) and healthy controls. Paired samples t-tests were used to determine differences between the PRE and POST time points within the FAIS group. The %VAF by PC 1 for the FAIS group at the PRE time point was significantly less than that of healthy controls (PRE: 77.2 ± 8.7% vs. Control: 96.1 ± 2.8%; p = 0.0001), and the % VAF of the second PC (PC2) was significantly greater [PRE: 22.8 (8.7)%; Control: 3.9 (2.8)%; p = 0.0001]. No differences in %VAF were found between the PRE and POST time points within the FAIS group for PC1 [PRE: 77.2 (8.7)% vs. POST: 79.3 (11.1)%; p = 0.472] or PC2 [PRE: 22.7 (8.7)%; POST: 20.7 (11.1)%; p = 0.472]. Significant differences in the plane specific contribution to the 3D motion coordination strategy were found between the FAIS patients at the PRE and POST time points for the sagittal plane [PRE: 5.6 (2.7) vs. POST: 0.91 (6.1); p = 0.012] and frontal plane [PRE: −10.4 (2.2) and −1.5 (6.3); p = 0.005]. Patients with FAIS demonstrated a more complex coordination strategy of 3D hip joint motion than controls and this strategy remains unchanged after hip arthroscopic surgery despite changes in the plane specific contribution to this strategy. These findings indicate that motor control impairments in FAIS patients do exist and seem to persist for at least 1 year after hip arthroscopic surgery.

Predicting the Risk of Subsequent Hip Surgery Before Primary Hip Arthroscopy for Femoroacetabular Impingement Syndrome: A Machine Learning Analysis of Preoperative Risk Factors in Hip Preservation

BACKGROUND

The number of patients requiring reoperation has increased as the volume of hip arthroscopy for femoroacetabular impingement syndrome (FAIS) has increased. The factors most important in determining patients who are likely to require reoperation remain elusive.

PURPOSE

To leverage machine learning to better characterize the complex relationship across various preoperative factors (patient characteristics, radiographic parameters, patient-reported outcome measures [PROMs]) for patients undergoing primary hip arthroscopy for FAIS to determine which features predict the need for future ipsilateral hip reoperation, namely, revision hip arthroscopy, total hip arthroplasty (THA), hip resurfacing arthroplasty (HRA), or periacetabular osteotomy (PAO).

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A cohort of 3147 patients undergoing 3748 primary hip arthroscopy procedures were included from an institutional hip preservation registry. Preoperative computed tomography of the hip was obtained for each patient, from which the following parameters were calculated: the alpha angle; the coronal center-edge angle; the neck-shaft angle; the acetabular version angle at 1, 2, and 3 o'clock; and the femoral version angle. Preoperative PROMs included the modified Harris Hip Score (mHHS), the Hip Outcome Score (HOS)-Activities of Daily Living subscale (HOS-ADL) and the Sport Specific subscale, and the international Hip Outcome Tool (iHOT-33). Random forest models were created for revision hip arthroscopy, the THA, the HRA, and the PAO. Area under the curve (AUC) for the receiver operating characteristic curve and accuracy were calculated to evaluate each model.

RESULTS

A total of 171 patients (4.6%) underwent subsequent hip surgery after primary hip arthroscopy for FAIS. The AUC and accuracy, respectively, were 0.77 (fair) and 76% for revision hip arthroscopy (mean, 26.4-month follow-up); 0.80 (good) and 81% for THA (mean, 32.5-month follow-up); 0.62 (poor) and 69% for HRA (mean, 45.4-month follow-up); and 0.76 (fair) and 74% for PAO (mean, 30.4-month follow-up). The most important factors in predicting reoperation after primary hip arthroscopy were higher body mass index (BMI) and lower preoperative HOS-ADL for revision hip arthroscopy, greater age and lower preoperative iHOT-33 for THA, increased BMI for HRA, and larger neck-shaft angle and lower preoperative mHHS for PAO.

CONCLUSION

Despite the low failure rate of hip arthroscopy for FAIS, our study demonstrated that machine learning has the capability to identify key preoperative risk factors that may predict subsequent ipsilateral hip surgery before the index hip arthroscopy. Knowledge of these demographic, radiographic, and patient-reported outcome data may aid in preoperative counseling and expectation management to better optimize hip preservation.

Gender and Age-Specific Differences Observed in Rates of Achieving Meaningful Clinical Outcomes 5-Years After Hip Arthroscopy for Femoroacetabular Impingement Syndrome

PURPOSE

To compare the impact of age and gender on achieving meaningful outcomes among minimum patients 5 years after undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS).

METHODS

Consecutive patients undergoing hip arthroscopy for FAIS by a single fellowship-trained surgeon between January 2012 and October 2014 were analyzed. Study inclusion criteria included any patient undergoing primary hip arthroscopy for FAIS, with 5 years follow-up. Preoperative and 5-year postoperative functional scores were collected, including the Hip Outcome Score Activities of Daily Living Subscale (HOS-ADL), HOS-Sport Subscale (HOS-SS), modified Harris hip score (mHHS), and Visual Analog Scale for satisfaction. Patients were matched 1:1 by gender and age to compare outcomes between these 2 demographics. Minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) were calculated for each functional measure and compared by gender and age.

RESULTS

Of the 340 patients (70.5%) with 5 years' follow up, 150 were matched by gender and age into one of the following groups: female patients <30 years, female patients 30 to 45 years, female patients >45 years, male patients <30 years, male patients 30 to 45 years, and male patients >45 years of age. At minimum 5-year follow-up, all 6 groups demonstrated statistically significant improvement in the functional outcome score averages and pain (P < .001 for all). Both within gender and within age category analysis of postoperative functional scores did not demonstrate any statistical differences (P > .05). Analysis of achieving MCID and PASS demonstrated that females had higher rates of reaching the HOS-SS and mHHS threshold for achieving MCID as compared to their male counterparts (P < .05). Furthermore, patients <30 years old had higher rates of reaching the HOS-ADL and mHHS for achieving PASS when compared to patients >45 years old (P < .05).

CONCLUSION

The majority of patients achieve clinically significant outcome improvement at 5-year follow-up after arthroscopic FAIS surgery. Females reach the mHHS threshold for achieving MCID at significantly higher rates than males. Patients <30 years of age achieved PASS on the HOS-ADL and mHHS threshold scores at higher rates than those >45 years old.

LEVEL OF EVIDENCE

Level III, case-control study.

Concomitant Lumbar Spinal Stenosis Negatively Affects Outcomes After Hip Arthroscopy for Femoroacetabular Impingement

PURPOSE

The purpose of this study was to assess the prognostic effect of lumbar spinal stenosis on clinical outcomes after hip arthroscopy for femoroacetabular impingement syndrome (FAI).

METHODS

Patients undergoing hip arthroscopy between September 2009 and December 2015 for FAI with concomitant lumbar spinal stenosis (central/neuroforaminal) and a 2-year follow-up were identified (hip-spine). A 1:1 case-matching query using preoperative modified Harris Hip Score (mHHS) within 3 points, body mass index (BMI) within 3 points, age within 5 years, and sex identified a control cohort without spinal pathology. Follow-up patient-reported outcomes (PROs) and clinical failure rates to revision procedure were compared using analysis of variance (ANOVA) and Kaplan-Meier survival analysis.

RESULTS

Twenty-six patients met criteria of the hip-spine group (age: 45.9 ± 12.2 years; BMI: 27.3 ± 5.0 kg/m², baseline mHHS: 44.17 ± 2.76) vs the control group (age: 46.2 ± 12.4 years, P = .94; BMI: 26.7 ± 4.1 kg/m², P = .61; baseline mHHS: 44.27 ± 2.82, P = .98). ANOVA analysis demonstrated that all PROs improved from baseline to 2-year outcomes (P < .001). The hip-spine vs control group had lower 1-year (mHHS: 65.97 ± 5.64 vs 85.04 ± 3.09, P = .006; nonarthritic hip score (NAHS): 70.26 ± 5.71 vs 87.89 ± 2.65, P = .010) and 2-year (mHHS: 69.72 ± 4.92 vs 84.71 ± 2.56, P = .007; NAHS: 72.23 ± 5.18 vs 87.14 ± 2.23, P = .008) outcomes. While there was no difference in patient acceptable symptomatic state (PASS) and minimal clinically important difference (MCID) rates at 1-year follow-up, the hip-spine group demonstrated lower PASS (42% vs 81%, P = .004) and MCID (58% vs 88%, P = .027) rates at 2 years. Although susceptible to type II error, there was no difference in clinical failure rates to revision procedure (P = .13).

CONCLUSIONS

While net PROs from baseline improve after hip arthroscopy for FAI, the presence of concomitant lumbar spinal stenosis negatively affects postoperative PROs. FAI patients with spinal stenosis should be counseled accordingly.

LEVEL OF EVIDENCE

Level III, case-control study.