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

Outcomes following open acetabular labrum reconstruction: Comparing fresh-frozen tendon with fresh meniscus allograft transplantation

Background

Symptomatic acetabular labral insufficiency in young, active patients is often treated with labral repair or reconstruction using fresh-frozen allografts. However, fresh-frozen tendon allografts do not have tissue or material properties that closely mimic acetabular labral fibrocartilage. Recent studies suggest meniscal allografts may be a better biomechanical, geometric, and material alternative for acetabular labrum reconstruction (ALR).

Hypothesis

Patients undergoing open ALR using fresh meniscus allograft transplants (MAT) will have better outcomes than those using fresh-frozen tendon allografts transplants (TAT) when comparing initial treatment success, diagnostic imaging assessments, and patient-reported pain and function scores.

Study design

Cohort Study.

Methods

With IRB approval, patients undergoing ALR with either TAT or MAT were included when initial (>1-year) outcomes data related to treatment success, pain, and function were available. In addition, a subcohort of patients underwent magnetic resonance imaging at least 6-months after surgery to evaluate allograft healing.

Results

Initial success rate, defined as no need for ALR revision or conversion to total hip arthroplasty (THA), was 88.9% for the entire group (n = 27, TAT = 5, MAT = 22) with 1 (20%) patient in the TAT cohort and 2 patients (9.9%) in the MAT cohort undergoing THA. In the MAT cohort, significant improvements were documented for physical function and pain scores at 1 year and final follow-up (FFU)(mean 26.8 months). Improvements in pain and function were noted at 1-year, but not at FFU (mean 59.6 months) in the TAT group. MRIs completed at least 6 months after labrum reconstruction showed improved allograft integrity and integration in the MAT cohort over the TAT cohort.

Conclusion

For acetabular labrum reconstructions, MAT was associated with a higher initial success rate, superior patient reported outcomes, and subjectively better MRI findings when compared to TAT.

Mid-term results of autologous matrix-induced chondrogenesis for large chondral defects in hips with femoroacetabular impingement syndrome

Aims

The purpose of this study was to evaluate the mid-term outcomes of autologous matrix-induced chondrogenesis (AMIC) for the treatment of larger cartilage lesions and deformity correction in hips suffering from symptomatic femoroacetabular impingement (FAI).

Methods

This single-centre study focused on a cohort of 24 patients with cam- or pincer-type FAI, full-thickness femoral or acetabular chondral lesions, or osteochondral lesions ≥ 2 cm2, who underwent surgical hip dislocation for FAI correction in combination with AMIC between March 2009 and February 2016. Baseline data were retrospectively obtained from patient files. Mid-term outcomes were prospectively collected at a follow-up in 2020: cartilage repair tissue quality was evaluated by MRI using the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. Patient-reported outcome measures (PROMs) included the Oxford Hip Score (OHS) and Core Outcome Measure Index (COMI). Clinical examination included range of motion, impingement tests, and pain.

Results

A total of 12 hips from 11 patients were included (ten males, one female, mean age 26.8 years (SD 5.0), mean follow-up 6.2 years (SD 5.2 months)). The mean postoperative MOCART score was 66.3 (SD 16.3). None of the patients required conversion to total hip arthroplasty. Two patients had anterior impingement. External hip rotation was moderately limited in four patients. There was a correlation between MOCART and follow-up time (rs = -0.61; p = 0.035), but not with initial cartilage damage, age, BMI, or imaging time delay before surgery. PROMs improved significantly: OHS from 37.4 to 42.7 (p = 0.014) and COMI from 4.1 to 1.6 (p = 0.025). There was no correlation between MOCART and PROMs.

Conclusion

Based on the reported mid-term results, we consider AMIC as an encouraging treatment option for large cartilage lesions of the hip. Nonetheless, the clinical evidence of AMIC in FAI patients remains to be determined, ideally in the context of randomized controlled trials.

Editorial Commentary: Osteochodral Autograft and Allograft Show Favorable Outcomes for High-Grade Hip Femoral Cartilage Lesions, but Caution Is Required for Impaction Injuries and Osteonecrosis

Articular cartilage defects of the hip pose therapeutic challenges. Among patients undergoing hip arthroscopy for femoroacetabular impingement syndrome, more than 20% may have partial- or full-thickness chondral damage, and patients with high-grade (International Cartilage Repair Society grade 3 or 4) damage who undergo arthroscopic treatment of femoroacetabular impingement syndrome have higher rates of reoperation at 10-year follow-up. Arthroscopic and open techniques have been developed to translate cartilage restoration options initially developed in the knee for use in the hip. Arthroscopic options include chondroplasty, microfracture, biologic cartilage scaffolds, autologous chondrocyte implantation, and minced cartilage autograft (albeit more commonly in the acetabulum than the femoral head). Open techniques include autologous chondrocyte grafting, osteochondral autograft transfer (including mosaicplasty), osteochondral allograft transplantation, and arthroplasty. Open osteochondral allograft and autograft transplantation show improved patient-reported outcomes and forestall arthroplasty in young patients with high-grade cartilage defects of the femoral head. A recent review shows survivorship of 70% to 87.5% for allograft and 61.5% to 96% for autograft. At the same time, outcomes are not universally positive, particularly for patients with posttraumatic impaction injuries and high-grade osteonecrosis. Until further data better clarify the indications and contraindications, widespread adoption of open cartilage transplantation to the femoral head should be approached with caution, especially for older patients, in whom the gold standard of total hip arthroplasty has excellent survivorship at long-term follow-up.

Intermediate-Term Outcomes of Hip Arthroscopy for Femoroacetabular Impingement Syndrome in Patients With Global Versus Isolated Lateral Acetabular Overcoverage

BACKGROUND

Previous studies evaluating the outcomes of hip arthroscopy for patients with global acetabular overcoverage and focal superolateral acetabular overcoverage suffer from short-term follow-up and inconsistent radiographic criteria when defining these subpopulations of patients with femoroacetabular impingement syndrome (FAIS).

PURPOSE

To evaluate the intermediate-term postoperative outcomes for patients with FAIS in the setting of global acetabular overcoverage, lateral acetabular overcoverage, and normal acetabular coverage.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients undergoing hip arthroscopy for FAIS were enrolled in a prospective cohort study, and those with a minimum follow-up of 5 years were included in this analysis. Patients were grouped based on type of acetabular coverage: global overcoverage (lateral center-edge angle [LCEA] ≥40°, with coxa profunda), lateral overcoverage (LCEA ≥40°, without coxa profunda), and no overcoverage (LCEA <40°). Functional outcomes (modified Harris Hip Score and Nonarthritic Hip Score) and failure of primary hip arthroscopy were compared between groups.

RESULTS

In total, 94 patients (mean age, 41.9 ± 14.2 years) were included with a mean follow-up duration of 6.1 ± 0.9 years. Of these patients, 40.4% had no acetabular overcoverage, 36.2% had lateral overcoverage, and 23.4% had global overcoverage. There was no difference between groups with respect to percentage of patients who underwent reoperation for either revision arthroscopy or conversion to total hip arthroplasty (28.9% for the normal acetabular coverage group, 29.4% for the lateral overcoverage group, and 31.8% for the global overcoverage group; P = .971). Among patients for whom primary hip arthroscopy did not fail, there was no difference in 5-year functional outcomes between groups. Postoperative LCEA >40° (β = -13.3; 95% CI, -24.1 to -2.6; P = .016), female sex (β = -14.5; 95% CI, -22.7 to -6.2; P = .001), and higher body mass index (β = -1.9; 95% CI, -2.8 to -1.0; P < .001) were associated with worse intermediate-term hip function in terms of modified Harris Hip Score.

CONCLUSION

There was no difference in functional outcomes or rate of reoperation at a minimum of 5 years postoperatively between those with global acetabular overcoverage, those with regional lateral overcoverage, and those with normal acetabular coverage. Provided that an appropriate acetabuloplasty is performed, there is no evidence to suggest that global acetabular overcoverage portends a worse prognosis than other FAIS subtypes.

Outcomes After Hip Arthroscopy Show No Differences Between Sexes: A Systematic Review

PURPOSE

To assess differences in postoperative outcomes between male and female patients following hip arthroscopy.

METHODS

A systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Medline, Embase, Cochrane, and PubMed databases were searched. Key words included "hip," "arthroscopy," "outcome," "gender difference," "sex difference," "gender," and "patient-reported outcome." Studies were included that reported sex-specific analysis of outcomes following primary hip arthroscopy with minimum 2-year follow-up. Methodological Index for Non-Randomized Studies criteria were applied to each study. Data collected included patient-reported outcome measures (PROMs), complications, rates of revision arthroscopy (RA), and conversion to total hip arthroplasty (THA). Forest plots were generated for the most frequently reported PROMs, RA, and THA rates.

RESULTS

In total, 38 studies met the inclusion criteria, with 40,194 (57% female) hips included. The most common indications for hip arthroscopy were femoroacetabular impingement and labral tears. Eighteen studies reported PROMs, with no clear trend towards sex differences. Eleven studies reported on RA rates, with 4 showing a significantly greater rate of RA in female patients. Seventeen studies reported on conversion to THA, with an overall conversion rate of 9.64%. There were no clear sex differences in conversion to THA.

CONCLUSIONS

There was no difference between sexes for postoperative PROM scores. Male patients were less likely to reach the MCID for the HOS-SSS than female patients in the majority of studies, and there were no sex differences for PASS rates. There were no significant differences between sexes in revision arthroscopy rates and conversion to total hip arthroplasty.

LEVEL OF EVIDENCE

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

High-Level Athletes With Borderline Hip Dysplasia Achieve Favorable Outcomes and Return to Sport Rates Following Primary Hip Arthroscopy: Minimum 5-Year Outcomes Comparison to a Propensity-Matched Control Group

PURPOSE

(1) To report minimum 5-year patient-reported outcomes (PROs) and return to sport (RTS) rates in high-level athletes with borderline hip dysplasia (BHD) following primary hip arthroscopy for labral pathology and femoroacetabular impingement syndrome and (2) to compare results to a propensity-matched control group of athletes with normal acetabular coverage.

METHODS

Data were reviewed for surgeries performed between February 2009 and February 2016. Patients were eligible if they underwent primary hip arthroscopy in the setting of BHD (lateral center-edge angle [LCEA] 18-25°) and competed in professional, collegiate, or high school sports. Inclusion criteria were preoperative and minimum 5-year follow-up scores for the modified Harris Hip Score (mHHS), Non-Arthritis Hip Score, Hip Outcome Score-Sport Specific Subscale (HOS-SSS), and visual analog scale for pain. Rates of achieving the minimal clinically importance difference (MCID), patient acceptable symptomatic state (PASS), and maximum outcome improvement satisfaction threshold (MOIST) were recorded in addition to RTS. BHD athletes were matched by age at the time of surgery, sex, body mass index, Tönnis grade, follow-up time, sport type, and competition level to a control group of 58 athletes with normal acetabular coverage (LCEA 25°-40°) for comparison.

RESULTS

A total of 34 BHD athletes were included with a mean follow-up of 73.6 ± 10.7 months. BHD athletes showed significant improvements in all PROs, demonstrated high RTS rates (90.0%), and achieved PASS/MCID/MOIST for mHHS (MCID: 80.0%, PASS: 93.3%, MOIST: 80.0%) and HOS-SSS (MCID: 76.7%, PASS: 73.3%) at high rates. When compared to a propensity-matched group with normal acetabular coverage, BHD athletes demonstrated similar postoperative PROs, rates of achieving psychometric thresholds, and RTS rates (P > .05). Additionally, by the latest follow-up, no athlete in either group required conversion to total hip arthroplasty.

CONCLUSIONS

High-level athletes with BHD undergoing primary hip arthroscopy for labral pathology and femoroacetabular impingement syndrome may expect favorable midterm outcomes and high RTS rates. These results were comparable to a control group of athletes with normal coverage.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Elite Female Athletes Demonstrate a Comparable Improvement in Midterm Patient-Reported Outcome Scores and Rate of Return to Sport Compared With Elite Male Athletes After Hip Arthroscopic Surgery: A Sex-Based Comparison in Professional and Collegiate Athletes

BACKGROUND

Few studies have compared outcomes, return to sport (RTS), and continuation of sport (CTS) after primary hip arthroscopic surgery between matched groups of male and female athletes with a minimum 5-year follow-up.

PURPOSE

(1) To report minimum 5-year patient-reported outcome (PRO) scores as well as RTS and CTS rates for elite female athletes undergoing hip arthroscopic surgery for femoroacetabular impingement syndrome (FAIS) and (2) to compare clinical results with those of a matched control group of elite male athletes.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected and retrospectively reviewed for elite (collegiate or professional) female athletes who underwent primary hip arthroscopic surgery for FAIS between March 2009 and March 2016. Inclusion criteria were preoperative and minimum 5-year scores for the modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score-Sport Specific Subscale, and visual analog scale for pain. Exclusion criteria were Tönnis grade >1, hip dysplasia, previous ipsilateral hip surgery/conditions, and those unwilling to participate. Rates of achieving the minimal clinically important difference (MCID), Patient Acceptable Symptom State (PASS), and maximum outcome improvement satisfaction threshold (MOIST) were recorded in addition to RTS. CTS was also recorded and defined as athletes reporting continued sport activity at a minimum 5-year follow-up after initially reporting returning to sport. Elite female athletes were propensity matched in a 1:1 ratio to elite male athletes for comparison.

RESULTS

A total of 81 hips in elite female athletes that underwent primary hip arthroscopic surgery met the inclusion criteria, and follow-up was available for 65 hips (80.2%) at a mean of 67.6 ± 6.5 months, with a mean age of 24.3 ± 6.8 years. Female athletes demonstrated significant improvements in all recorded PRO scores; achieved the MCID, PASS, and MOIST at high rates; returned to sport at a rate of 80.4%; and continued sport at a rate of 97.1%. Female athletes demonstrated lower preoperative PRO scores compared with male athletes, but postoperative PRO scores; improvements in scores; rates of achieving the MCID, PASS, MOIST; and RTS and CTS rates were similar between female and male athletes.

CONCLUSION

Elite female athletes undergoing primary hip arthroscopic surgery for FAIS demonstrated favorable PRO scores and high RTS and CTS rates at a minimum 5-year follow-up. These results were comparable with those of a propensity-matched control group of elite male athletes.

Hip Arthroscopic Microfracture Augmented With Platelet-Rich Plasma-Infused Micronized Cartilage Allograft Significantly Improves Functional Outcomes

PURPOSE

To evaluate functional outcomes and survivorship in patients at 1 year after undergoing arthroscopic microfracture augmented with hyaline allograft for symptomatic chondral defects of the hip.

METHODS

Consecutive patients with and without prior hip procedures presenting with Outerbridge grade IV chondral lesion of the acetabulum or femoral head were prospectively followed. Patients underwent hip microfracture augmented with hyaline allograft suspended in autologous platelet-rich plasma between October 2016 and April 2018. Extent of cartilage degeneration was quantified using the chondromalacia severity index (CMI). Patient functional scores, including Tegner, Hip Outcome Score-Activities of Daily Living (HOS-ADL), Sport-Specific Subscale (HOS-SSS), modified Harris Hip Score (mHHS), and Nonarthritic Hip Score (NAHS) were collected preoperatively and at minimum 1-year postoperatively. Minimal clinically important difference (MCID) was analyzed. Statistical significance was established at P < .05. Pearson's coefficient analysis was performed to identify preoperative variables correlated with clinical outcomes.

RESULTS

Fifty-seven patients (86.4%) had minimum 1-year follow-up and were included in the final analysis, with a mean age and body mass index (BMI) of 38.3 ± 9.1 years and 27.7 ± 4.9 kg/m², respectively. Comparison of baseline and postoperative score averages demonstrated significant improvements in Tegner scores (3.7 ± 2.9 vs 5.1 ± 2.6; P = .003), HOS-ADL (63.3 ± 16.4 vs 89.1 ± 14.5; P < .001), HOS-SSS (40.8 ± 20.4 vs 79.5 ± 21.6; P < .001), mHHS (61.5 ± 16.2 vs 87.0 ± 17.7; P < .001), and NAHS (56.6 ± 14.9 vs 78.7 ± 18.3; P < .001). The percentage of patients who achieved MCID for HOS-ADL, HOS-SSS, mHHS, and NAHS were 89.8%, 83.0%, 75.6%, and 81.6%, respectively. Overall, 91.8% of patients met the threshold for achieving MCID in at least one outcome score. Of the 57 patients, 5 (8.8%) failed clinically, with 1 (1.8%) undergoing revision surgery and 4 (6.9%) undergoing conversion to total hip arthroplasty. There was a direct correlation between preoperative alpha angle and postoperative HOS-ADL. Femoral chondral lesion size and CMI inversely correlated with postoperative HOS-ADL.

CONCLUSIONS

Treatment of hip chondral defects with microfracture and hyaline allograft augmentation demonstrated excellent survivorship and significantly improved patient report outcomes at 1 year.

LEVEL OF EVIDENCE

IV, retrospective case series.

Hip Spine Syndrome Negatively Impacts Arthroscopic Outcomes in the Management of Femoroacetabular Impingement Syndrome: A Systematic Review

To determine whether the presence of spine pathology affects clinical outcomes after hip arthroscopy for femoroacetabular impingement syndrome (FAIS) in the setting of hip-spine syndrome (HSS) METHODS: A systematic review of PubMed and Cochrane was conducted. Primary research articles evaluating patient-reported outcomes (PRO) after hip arthroscopy for FAIS in the presence of concomitant spine pathology were considered RESULTS: Literature review identified 12 studies meeting criteria. In 2109 FAIS patients undergoing hip arthroscopy, 591 had concomitant spine pathology. Baseline PROs in the hip-spine (modified Harris Hip Score [mHHS]: 39.8-65.29 vs 56.9-78.8, 8 studies; non-arthritic hip score [NAHS]: 42.2-51.5 vs 68.2-75.2, 4 studies; hip outcome score-activities of daily living [HOS-ADL]: 45.9-71.1 vs 49.3-89.51, 9 studies; hip outcome score-Sport (HOS-Sport): 22.8-49.6 vs 50.6-73.1, 3 studies; international hip outcome tool-33 [iHOT-12]: 38.0 vs 66.0, 1 study; visual analog scale [VAS] Pain: 6.43-6.56 vs 1.18-3.60, 3 studies; VAS Satisfaction: 7.18-7.46 range at follow-up, 2 studies) and control (mHHS: 39.3-64.9 vs 70.2-92.6, 6 studies; NAHS: 42.8-54.2 vs 74.0-87.1, 4 studies; HOS-ADL: 59.0-76.4 vs 75.4-97.1, 4 studies; HOS-Sport: 38.1-55.1 vs 60.9-93.9, 3 studies; iHOT-12: 43.4 vs 89.8, 1 study; VAS Pain: 6.18-6.22 vs 1.82-3.44, 2 studies; VAS Satisfaction: 7.74-8.22 range at follow up, 2 studies). Minimal clinically important difference threshold rates achieved in the hip-spine (44.1-86.7, 4 studies) cohorts were significantly lower than control (79.4-88.2%; 4 studies) cohorts in 3 studies. Patient-acceptable symptomatic state threshold rates achieved in the hip-spine (42-63.5, 3 studies) cohorts were significantly lower than control (58.8-81.0, 3 studies) in 1 study. There was no statistical difference in complication and reoperation rates between cohorts CONCLUSION: FAIS patients with concomitant HSS have improved but inferior outcomes after hip arthroscopy compared to patients without HSS LEVEL OF EVIDENCE: IV, systematic review.

Acellular Matrix-Induced Chondrogenesis Technique Improves the Results of Chondral Lesions Associated With Femoroacetabular Impingement

PURPOSE

The study's main objective was to evaluate, in the short-term, the result of the autologous acellular matrix-induced chondrogenesis (AMIC) technique in a selected group of patients with 2-4 cm² full-thickness chondral lesions, undergoing hip arthroscopy for femoroacetabular impingement (FAI).

METHODS

A retrospective single-center Level IV case series of 25 patients (28 hips) who underwent an arthroscopic hip surgery with a liquid acellular collagen matrix. Inclusion criteria for implantation were FAI diagnosis (cam or pincer type), grade IV chondral lesions (Outerbridge size 2-4 cm²); Tönnis stage 0-II, minimum follow-up of 24 months, and 1 year (12-15 months) evaluation with very high field 3-T MRI arthrography. Exclusion criteria were Tönnis III, joint space <2 mm, center-edge angle <20°, and <24 months of follow-up. Clinical assessments involved symptoms duration until surgery, changes in physical and work activity and range of motion, modified Harris Hip Score, reporting percentages of patient acceptable symptomatic state (PASS) and minimal clinically important difference (MCID), pain with a VAS, and level of satisfaction. Radiological assessments: Tönnis stage, articular space, alpha and lateral center edge angle (Wiberg), and generated tissue characteristics at 1 year (based on the MOCART score), through 3-T MRI.

RESULTS

25 patients (28 hips) treated; 19 men and 6 women (mean age: 40.5 years; range: 25-55). Two women underwent joint replacement surgery. Thus, 23 patients (26 hips) were analyzed. At 29 months following surgery (range: 24-48), a significant improvement was obtained in all parameters assessed, focusing on the characteristics of the generated tissue in the MRI (MOCART scores). 95% of the patients met the MCID (improvement >12 points in the modified Harris Hip Score), and 100% scored >74 points, achieving the PASS. Patients' satisfaction was 86.6% (SD 16.4). All patients who practiced sports resumed them.

CONCLUSIONS

The liquid AMIC is a safe technique that shows good clinical and radiological outcomes in a 2-year follow-up in patients with femoroacetabular impingement and grade IV acetabular 2-4 cm² chondral defects.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Application of Machine Learning Algorithms to Predict Clinically Meaningful Improvement After Arthroscopic Anterior Cruciate Ligament Reconstruction

Background:

Understanding specific risk profiles for each patient and their propensity to experience clinically meaningful improvement after anterior cruciate ligament reconstruction (ACLR) is important for preoperative patient counseling and management of expectations.

Purpose:

To develop machine learning algorithms to predict achievement of the minimal clinically important difference (MCID) on the International Knee Documentation Committee (IKDC) score at a minimum 2-year follow-up after ACLR.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

An ACLR registry of patients from 27 fellowship-trained sports medicine surgeons at a large academic institution was retrospectively analyzed. Thirty-six variables were tested for predictive value. The study population was randomly partitioned into training and independent testing sets using a 70:30 split. Six machine learning algorithms (stochastic gradient boosting, random forest, neural network, support vector machine, adaptive gradient boosting, and elastic-net penalized logistic regression [ENPLR]) were trained using 10-fold cross-validation 3 times and internally validated on the independent set of patients. Algorithm performance was assessed using discrimination, calibration, Brier score, and decision-curve analysis.

Results:

A total of 442 patients, of whom 39 (8.8%) did not achieve the MCID, were included. The 5 most predictive features of achieving the MCID were body mass index ≤27.4, grade 0 medial collateral ligament examination (compared with other grades), intratunnel femoral tunnel fixation (compared with suspensory), no history of previous contralateral knee surgery, and achieving full knee extension preoperatively. The ENPLR algorithm had the best relative performance (C-statistic, 0.82; calibration intercept, 0.10; calibration slope, 1.15; Brier score, 0.068), demonstrating excellent predictive ability in the study’s data set.

Conclusion:

Machine learning, specifically the ENPLR algorithm, demonstrated good performance for predicting a patient’s propensity to achieve the MCID for the IKDC score after ACLR based on preoperative and intraoperative factors. The femoral tunnel fixation method was the only significant intraoperative variable. Range of motion and medial collateral ligament integrity were found to be important physical examination parameters. Increased body mass index and prior contralateral surgery were also significantly predictive of outcome.

Achieving Successful Outcomes in High-Level Athletes With Borderline Hip Dysplasia Undergoing Hip Arthroscopy With Capsular Plication and Labral Preservation: A Propensity-Matched Controlled Study

BACKGROUND

Return to sports (RTS) rates and patient-reported outcomes (PROs) after hip arthroscopy in athletes with borderline dysplasia (BD) have not been established.

PURPOSE

(1) To report minimum 2-year PROs and RTS rates in high-level athletes with BD who underwent hip arthroscopy for labral pathology in the setting of microinstability and (2) to compare clinical results with those of a matched control group of athletes with normal acetabular coverage.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were reviewed for surgery performed between January 2012 and July 2018. Patients were considered eligible if they received a primary hip arthroscopy in the setting of BD (lateral center-edge angle, 18°-25°) and competed in professional, collegiate, or high school sports. Inclusion criteria included preoperative and minimum 2-year follow-up scores for the modified Harris Hip Score, Non-arthritic Hip Score, Hip Outcome Score-Sport Specific Subscale, and visual analog scale for pain. Athletes with BD were matched to a control group of athletes with normal acetabular coverage (lateral center-edge angle, 25°-40°).

RESULTS

A total of 65 patients with BD were included in the study with a mean ± standard deviation follow-up of 47.5 ± 20.4 months. Athletes with BD showed significant improvement in all outcome measures recorded, demonstrated high RTS rates (80.7%), and achieved the minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) for the Hip Outcome Score-Sport Specific Subscale at high rates (MCID, 90.8%; PASS, 75.4%). When compared with a propensity-matched control group with normal acetabular coverage, capsular plication was performed more commonly in the BD group (93.8% vs 82.7%; P = .037). PROs and RTS, PASS, and MCID rates were similar between the BD and control groups (P > .05).

CONCLUSION

High-level athletes with BD who undergo primary hip arthroscopy for labral pathology in the setting of microinstability may expect favorable PROs and RTS rates at minimum 2-year follow-up. These results were comparable with those of a control group of athletes with normal coverage.

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.

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

PURPOSE

To (1) compare the rates of reaching threshold hip-specific outcome scores for achieving the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) in patients who underwent partial versus complete T-capsulotomy repair and (2) identify the failure rates in each group 5 years after undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS).

METHODS

Data from consecutive patients who underwent hip arthroscopy for FAIS performed by a single fellowship-trained surgeon from January 2011 to March 2013 were collected and analyzed. Baseline data, hip-specific outcomes, and clinical failure rates were recorded at a minimum of 5 years postoperatively. Patients with partial T-capsulotomy repair were matched 1:3 by age, body mass index, and sex to patients with complete T-capsulotomy repair. Threshold scores for achieving the MCID and PASS were calculated and compared between the 2 groups. Additionally, rates of revision and conversion to total hip arthroplasty (THA) were compared between the groups.

RESULTS

A total of 379 patients were available for analysis (39 partial and 340 complete repairs), with 100 patients included in the matching process (25 in the partial-repair group and 75 in the complete-repair group). Comparison of radiographic parameters, including the Tönnis grade, alpha angle, and lateral center-edge angle, between the 2 groups showed no statistically significant difference (P > .05 for all). Comparison of postoperative score averages between the partial- and complete-closure groups showed a significant difference in the Hip Outcome Score-Activities of Daily Living Subscale (85.4 ± 17.7 vs 94.6 ± 7.8, P < .001), Hip Outcome Score-Sports Subscale (76.6 ± 26.2 vs 89.3 ± 16.8, P = .034), modified Harris Hip Score (83.2 ± 19.7 vs 90.5 ± 11.2, P = .035), and visual analog scale pain score (24.5 ± 30.8 vs 13.4 ± 15.8, P = .035). A total of 65 complete-repair patients (95.6%) achieved the MCID for at least 1 outcome measure versus 18 patients with partial repair (78.3%) (P = .04). A total of 69 complete-repair patients (92%) achieved the PASS for at least 1 outcome measure versus 18 partial-repair patients (72%) (P = .017). Of the 39 partial-repair patients, 35.9% (n = 14) underwent revision or conversion to THA, as compared with 2.9% (n = 10) in the overall cohort.

CONCLUSIONS

At a minimum 5-year follow-up, patients with complete capsular closure after hip arthroscopy for FAIS show superior long-term outcomes and achieve higher rates of meaningful clinical success when compared with patients with partial capsular closure. Furthermore, patients with partial capsular repair undergo revision or conversion to THA at high rates.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Hip Arthroscopy for Femoroacetabular Impingement Syndrome in Adolescents Provides Clinically Significant Outcome Benefit at Minimum 5-Year Follow-Up

PURPOSE

To report the rates of achieving clinically significant outcomes as defined by the minimal clinically important difference (MCID), patient acceptable symptomatic state (PASS), or substantial clinical benefit (SCB) in adolescent patients and the rates of clinical failure 5 years after undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS).

METHODS

Data from consecutive adolescent patients (defined by the American Academy of Pediatrics as age 11 to 21 years) who underwent primary hip arthroscopy with routine capsular closure for the treatment of FAIS between January 2012 and January 2015 by a single, fellowship-trained surgeon was collected. Baseline data, clinical outcomes including Hip Outcome Score (HOS)-Activities of Daily Living, HOS-Sports Subscale, modified Harris hip score, international Hip Outcome Tool, and clinical failure rates were recorded at 5 years after operative. Clinical failure was defined by revision hip arthroscopy or conversion to total hip arthroplasty. Clinically significant outcomes was defined as achieving MCID, PASS, or SCB on at least 1 hip-specific outcome measure.

RESULTS

Of the 139 eligible patients, a total of 85 (60.4%) patients (85 hips) were included in the final analysis, with an age and body mass index average of 17.6 ± 2.5 years (range 13-21) and 22.3 ± 3.1 kg/m², respectively. The majority of the patients were female (80.6%) and participated in sports (76.2%). There was statistically significant difference between preoperative and postoperative score averages across every reported outcome (P < .001). At 5 years, 88.4%, 67.6%, and 64.9% reached at least 1 threshold for achieving MCID, PASS, and SCB, respectively, whereas 89.2% achieved at least one of the meaningful outcome thresholds. Last, 2 patients (2.4%) failed clinically, with both undergoing revision (2.4%) because of continued pain. There were no conversions to total hip arthroplasty.

CONCLUSION

This study demonstrated that a large majority (89.2%) of adolescent patients undergoing primary arthroscopic treatment for symptomatic FAIS achieved meaningful clinically significant outcomes. Furthermore, only 2.4% of patients failed clinically, requiring revision hip arthroscopy because of continued pain.

LEVEL OF EVIDENCE

IV, Retrospective Case Series.

Evaluation of outcome reporting trends for femoroacetabular impingement syndrome- a systematic review

PURPOSE

The aim of this systematic review was to evaluate the trends in the literature regarding surgical treatment for femoroacetabular impingement syndrome (FAIS) and to present which patient-reported outcome-measures (PROMs) and surgical approaches are included.

METHODS

This systematic review was conducted with the PRISMA guidelines. The literature search was performed on PubMed and Embase, covering studies from 1999 to 2020. Inclusion criteria were clinical studies with surgical treatment for FAIS, the use of PROMs as evaluation tool and studies in English. Exclusion criteria were studies with patients < 18 years, cohorts with < 8 patients, studies with primarily purpose to evaluate other diagnoses than FAIS and studies with radiographs as only outcomes without using PROMs. Data extracted were author, year, surgical intervention, type of study, level of evidence, demographics of included patients, and PROMs.

RESULTS

The initial search yielded 2,559 studies, of which 196 were included. There was an increase of 2,043% in the number of studies from the first to the last five years (2004-2008)-(2016-2020). There were 135 (69%) retrospective, 55 (28%) prospective and 6 (3%) Randomized Controlled Trials. Level of evidence ranged from I-IV where Level III was most common (44%). More than half of the studies (58%) originated from USA. Arthroscopic surgery was the most common surgical treatment (85%). Mean follow-up was 27.0 months (± 17 SD), (range 1.5-120 months). Between 1-10 PROMs were included, and the modified Harris Hip Score (mHHS) was most commonly used (61%).

CONCLUSION

There has been a continuous increase in the number of published studies regarding FAIS with the majority evaluating arthroscopic surgery. The mHHS remains being the most commonly used PROM.

Association between severity of hip chondrolabral injuries, dynamic hip muscle strength and quality of life: A cross-sectional study in patients with femoroacetabular impingement syndrome scheduled for hip arthroscopy

BACKGROUND

We assessed the association between: the severity of hip chondral or labral pathology with dynamic hip muscle strength or quality of life in patients with femoroacetabular impingement syndrome scheduled for hip arthroscopy. We also assessed the association between dynamic hip muscle strength with quality of life.

METHODS

Eighty-three participants with femoroacetabular impingement syndrome scheduled for hip arthroscopy were included. We measured dynamic hip abduction and adduction muscle strength with an isokinetic dynamometer (Nm/kg), and quality of life with the iHoT-33 questionnaire. The severity of hip chondrolabral pathologies was scored using the modified Beck classification. Linear regression analyses were conducted to assess the association between severity of hip chondral or labral pathology with dynamic hip muscle strength and quality of life.

FINDINGS

The regression analyses showed no association between the (i) severity of hip chondral (adjusted r²: 0.14) or labral (adjusted r²: 0.08) pathology and quality of life (P > 0.05), (ii) between the severity of hip chondral or labral pathology and dynamic hip abduction and adduction muscle strength (P > 0.05). Significant correlation was observed for quality of life and hip abduction (adjusted r²:0.29; P < 0.001) or adduction (adjusted r²: 0.32; P < 0.001) muscle strength.

INTERPRETATION

The severity of hip chondral or labral pathologies were not associated with quality of life or dynamic hip muscle strength in participants with femoroacetabular impingement syndrome. Greater dynamic hip abduction and adduction muscle strength were associated with better quality of life in participants with femoroacetabular impingement syndrome scheduled for hip arthroscopy.

Large Heterogeneity Among Minimal Clinically Important Differences for Hip Arthroscopy Outcomes: A Systematic Review of Reporting Trends and Quantification Methods

PURPOSE

To perform a systematic review of reporting trends and quantification methods for the minimal clinically important difference (MCID) within the hip arthroscopy literature.

METHODS

Cochrane, PubMed, and OVID/MEDLINE databases were queried for hip arthroscopy articles that reported the MCID. Studies were classified as (1) calculating new MCID values for their specific study-population or (2) referencing previously established MCID values. Data pertaining to patient demographics, study characteristics, outcome measures, method of MCID quantification, MCID value, anchor questions, measurement error, and study from which referenced MCID values were obtained were extracted.

RESULTS

A total of 59 articles with 18,830 patients (19,867 hips) was included. A total of 19 unique outcome measures was reported. A total of 33 (n = 55.9%) studies (follow-up range 6-60 months) used previously established MCID values to assess their study population (MCID values established at a follow-up range 6-31 months). The remaining 26 studies (44.1%) performed new MCID calculations. The MCID values were inconsistent and varied widely (Hip Outcome Score-Activities of Daily Living: 5.0-15.4; Hip Outcome Score-Sports Subscale: 6-25; modified Harris hip score: 2.4-20.9). Among the 33 studies that used previously established MCID values, 10 different studies were cited as the reference. Among the remaining 26 studies that calculated a new MCID value, the most common method was 0.5 standard deviation method (n = 21, 80.8%). Only 3 of 26 (11.5%) studies reported a measurement of error in conjunction with their MCID values.

CONCLUSIONS

Inconsistencies in MCID reporting and quantification methods led to a wide range of MCID values for commonly administered outcome measures within the hip arthroscopy literature-even for the same outcome measures. The majority of studies referenced previously established MCID values with variable ranges of follow-up and applied those values to assess their specific study population at varying follow-ups.

LEVEL OF EVIDENCE

IV, systematic review.

Hip Arthroscopy for Femoroacetabular Impingement: 1-Year Outcomes Predict 5-Year Outcomes

BACKGROUND

Limited evidence exists comparing short- and long-term patient-reported outcomes (PROs) and overall survival rates after hip arthroscopy for femoroacetabular impingement syndrome (FAIS).

HYPOTHESIS

Patients with high improvement (HI) versus low improvement (LI) at 1 year postoperatively would achieve higher PROs and better index procedure survival rates at 5-year follow-up.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who underwent primary hip arthroscopy for FAIS between September 2012 and March 2014 with minimum 5-year outcome data were identified. Using the median 1-year change in modified Harris Hip Score (mHHS) as a threshold, HI and LI subcohorts were determined. Analysis of variance was used to compare PROs. Failure rates were determined using Kaplan-Meier and Cox proportional hazards model analyses. Regression analysis was used to identify factors associated with increasing 5-year change in mHHS and Nonarthritic Hip Score (NAHS).

RESULTS

Out of 108 eligible consecutive patients, 89 (82.4%) were included (mean [SD]: age, 43.3 [14.6] years; body mass index, 25.4 [4.5]). As compared with the LI group (n = 45), the HI group (n = 44) had a longer 5-year index surgery survival rate (mean ± SEM: 83.7 ± 3.3 months vs 68.5 ± 4.6 months; P = .012) and 5-year estimated survival rate (89% vs 71%). The HI group had a decreased risk of failure versus the LI group (hazard ratio, 0.15; P = .002). The HI group also had greater PROs than did the LI group at 1 year (mHHS: 94.8 ± 1.2 vs 72.6 ± 2.7, P < .001; NAHS: 94.0 ± 1.3 vs 75.6 ± 2.2, P < .001) and 5 years (mHHS: 86.9 ± 2.0 vs 77.6 ± 3.4, P = .017; NAHS: 92.6 ± 1.8 vs 82.7 ± 4.1, P = .020). As compared with the LI group, the HI group achieved higher rates of the Patient Acceptable Symptomatic State (PASS) and minimal clinically important difference (MCID) at 1 year (PASS: 95% vs 42%, P < .001; MCID: 100% vs 89%, P = .056) and 5 years (PASS: 77% vs 45%, P = .002; MCID: 86% vs 64%, P = .014). Linear regression demonstrated that being in the HI group (ΔmHHS, P = .041; ΔNAHS, P = .017) and decreasing body mass index (ΔmHHS, P = .055; ΔNAHS, P = .023) were associated with higher 5-year ΔPROs.

CONCLUSION

Patients with FAIS and significant improvement in the first year after hip arthroscopy had superior 5-year outcomes versus patients with persistent symptom severity. Survival rates and PROs were significantly better in patients who achieved high early outcomes at the 1-year mark.

Age and Outcomes in Hip Arthroscopy for Femoroacetabular Impingement: A Comparison Across 3 Age Groups

BACKGROUND

Limited evidence exists concerning the effect of age on hip arthroscopy outcomes for femoroacetabular impingement (FAI).

PURPOSE/HYPOTHESIS

The purpose was to investigate patient-reported outcomes (PROs) and clinical failure rates across various age groups in patients undergoing hip arthroscopy for FAI. We hypothesized that older patients would experience lower improvements in PROs and higher clinical failure rates.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 109 of 130 eligible consecutive patients underwent hip arthroscopy for FAI with a minimum 5-year follow-up. Patients were stratified into 3 groups for comparison (ages 15-34, 35-50, and 51-75 years). Clinical survival rates to revision surgery or total hip arthroplasty (THA) were determined by Kaplan-Meier analysis, and PROs were assessed using analysis of variance. Regression analysis was used to determine factors associated with clinical failure and ΔPROs from baseline to 5 years.

RESULTS

The 5-year survival-to-revision rate was 71% (survival time, 69.2 months; 95% CI, 62.8 to 75.5 months). A significant difference in survival to THA was found between groups (P = .030). Being in the older group versus the young and middle-aged groups predicted increased risk of THA conversion (hazard ratio, 5.7; 95% CI, 1.1 to 28.6; P = .035). Overall modified Harris Hip Score (mHHS) and Nonarthritic Hip Score (NAHS) improved from baseline to 5 years (mHHS, P < .001; NAHS, P < .001). Body mass index (mHHS: beta, -1.2; 95% CI, -2.2 to -0.3; P = .013; NAHS: beta, -1.6; 95% CI, -2.6 to -0.5; P = .005) and baseline PROs (mHHS: beta, -0.8; 95% CI, -1.1 to -0.4; P < .001; NAHS: beta, -0.7; 95% CI, -1.1 to -0.4; P < .001) were predictive of 5-year ΔPROs. A decrease was seen in minimal clinically important difference rates in middle-aged (P = .011) and old (P = .030) groups from 6-month to 5-year outcomes.

CONCLUSION

Although hip arthroscopy for FAI yielded improvements in PROs regardless of age, middle-aged and older patients experienced greater declines in clinical outcomes over time than younger patients. Older patients remain good candidates for arthroscopy despite a greater risk for conversion to THA.

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

BACKGROUND

Hip arthroscopy for the treatment of femoroacetabular impingement syndrome (FAIS) in patients with borderline hip dysplasia (BHD) is becoming a more common practice. However, the literature on achieving meaningful outcomes at midterm follow-up, as well as predictors of these outcomes, is limited.

PURPOSE

To (1) compare the rates of achieving meaningful clinical outcomes between patients with and without BHD and (2) identify the predictors for achieving clinical success among patients with BHD 5 years after undergoing hip arthroscopic surgery for FAIS.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data from consecutive patients who underwent primary hip arthroscopic surgery with routine capsular closure for the treatment of FAIS between January 2012 and August 2014 were collected and retrospectively analyzed. Patients with BHD (lateral center-edge angle [LCEA] 20°-25°) were matched 1:2 by age (±1 year) and body mass index (BMI; ±5 kg/m²) to control patients with normal acetabular coverage (LCEA 25°-40°). Data collected included baseline and 5-year postoperative patient-reported outcomes. The minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) were calculated for each patient-reported outcome measure and compared between the 2 groups. A binary logistic regression analysis was used to identify significant predictors of achieving the MCID and PASS in the BHD group.

RESULTS

The MCID in the BHD group was defined as 9.6, 14.1, and 9.5 for the Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sports Subscale, and modified Harris Hip Score, respectively. Threshold scores for achieving the PASS in both groups were 90.9, 76.6, and 81.9, respectively. A total of 88 patients were identified with having BHD and were matched to 176 controls. No statistical differences were identified for age, BMI, or sex. Both the BHD and the non-BHD groups had statistically significant increases in patient-reported outcome scores over the 5-year period, but the difference in both groups was not statistically significant (P > .05 for all). There was no statistical difference in the frequency of patients in the BHD and non-BHD groups achieving the MCID (86.6% vs 85.2%, respectively; P = .804) or PASS (76.0% vs 73.7%, respectively; P = .675) on at least 1 outcome measure. The logistic regression model demonstrated that being physically active (odds ratio [OR], 27.59; P = .005) and being female (OR, 14.64; P = .025) were independent predictors of achieving the MCID, while running (OR, 11.1; P = .002), being female (OR, 7.6; P = .011), and a larger preoperative LCEA (OR, 2.3; P = .001) were independent preoperative predictors of achieving the PASS.

CONCLUSION

The rates of achieving clinical success 5 years after undergoing arthroscopic treatment with capsular closure for FAIS were not significantly different between patients with BHD and those with normal acetabular coverage. Being physically active, running for exercise, female sex, and a larger LCEA were preoperative predictors of achieving clinical success at 5 years in patients with BHD.

What is the Role of Kinesiophobia and Pain Catastrophizing in Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome?

Purpose

To (1) investigate trends in kinesiophobia and pain catastrophizing after hip arthroscopy for femoroacetabular impingement syndrome (FAIS), and (2) determine whether kinesiophobia and pain catastrophizing scores are associated with achieving minimal clinically important difference (MCID) for any of the hip-specific patient-reported outcome questionnaires.

Methods

Patients undergoing primary hip arthroscopy for treatment of FAIS between December 2016 and March 2017 were prospectively enrolled. Patients received the Tampa Scale of Kinesiophoibia-11 (TSK-11) and Pain Catastrophizing Scale (PCS) questionnaires preoperatively, 6 months, and 1 year postoperatively. They also received the hip-specific patient-reported outcome questionnaires (Hip Outcome Score Activities of Daily Living and Sport-Specific subscales, modified Harris Hip Score, and International Hip Outcome Tool-12), as well as visual analog scale for satisfaction and pain preoperatively and 1-year postoperatively. The threshold for achieving MCID was determined for each hip outcome tool, and patients achieving MCID were compared with those who did not.

Results

A total of 85 (80.2%) patients (mean age: 33.7 ± 12.4 years; female: 75.3%) were included in the final analysis. At 1-year follow-up, there was a significant reduction in TSK-11 scores (26.22 ± 5.99 to 18.70 ± 6.49; P < .001) and PCS scores (17.81 ± 10.13 to 4.77 ± 7.57; P < .001) when compared with preoperative scores. 1-year PCS scores were significantly lower in patients achieving MCID compared with patients failing to achieve MCID (3.2 ± 4.4 vs 10.8 ± 15.2; P = .006). There were no significant differences in TSK-11 scores between those achieving and not achieving MCID.

Conclusions

Patient kinesiophobia and pain catastrophizing both show significant improvements 1 year after undergoing hip arthroscopy for FAIS. However, pain catastrophizing scores at 1 year are significantly greater in patients not achieving MCID, whereas no association was identified between kinesiophobia and likelihood for MCID achievement. This suggests PCS may be a more useful tool than TSK-11 during postoperative rehabilitation for identifying patients at risk for not achieving MCID.

Level of Evidence

Level II, prospective case series.