What Are the Risk Factors for Revision Surgery After Hip Arthroscopy for Femoroacetabular Impingement at 7-year Followup?

Hip arthroscopy with initial access to the peripheral compartment for femoroacetabular impingement: midterm results from a large-scale patient cohort

BACKGROUND

Hip arthroscopy with initial access to the peripheral compartment could reduce the risk of iatrogenic injury to the labrum and cartilage; furthermore, it avoids the need for large capsulotomies with separate portals for peripheral and central (intra-articular) arthroscopy. Clinical results of the peripheral-compartment-first technique remain sparse, in contrast to those of conventional hip arthroscopy starting in the intra-articular central compartment. The purpose of this study was to assess outcome of hip arthroscopy with the peripheral-compartment-first technique, including complication rates, revision rates and patient-reported outcome scores.

MATERIALS AND METHODS

This outcome study included 704 hips with femoroacetabular impingement. All arthroscopies were performed using the peripheral-compartment-first technique. A joint replacement registry and the institutional database were used to assess the revision and complication rates, while patient-reported outcome measures were used to assess functional outcomes and patient satisfaction.

RESULTS

In total, 704 hips (615 patients) were followed up for a mean of 6.2 years (range 1 to 9 years). The mean age of the patients was 32.1 ± 9.2 years. During the follow-up period, 26 of 704 (3.7%) hips underwent total hip arthroplasty (THA) after a mean of 1.8 ± 1.2 years, and 18 of the 704 (2.6%) hips required revision hip arthroscopy after a mean of 1.2 ± 2.1 years. 9.8% of the hips had an unsatisfactory patient-reported outcome at final follow-up.

CONCLUSIONS

The results for the peripheral-compartment-first technique were promising. We recommend a well-conducted randomized controlled clinical trial to guide future therapeutic recommendations regarding the most favorable hip arthroscopy technique.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

TRIAL REGISTRATION

This study was registered at ClinicalTrials.gov (U.S. National Library of Medicine; ID: NCT05310240).

Socioeconomic factors including patient income, education level and health insurance influence post-operative 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 PearlDiverTM Mariner database from October 2015 to January 2020 for patients undergoing hip arthroscopy with 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). 2-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-$70,000 had lower odds of 2-year revision arthroscopy [OR = 0.63, p < 0.001], THA conversion [OR= 0.76, p= 0.050], and 90-day readmission [OR= 0.53, p= 0.007] compared to MFIR >$100,000. Compared to patients with commercial insurance, patients with Medicare had lower odds of revision arthroscopy [OR= 0.60, p= 0.035] and THA conversion [OR= 0.46, p< 0.001], but greater odds of 90-day readmission [OR= 1.74, p= 0.007]. Patients with Medicaid had higher odds of 90-day ED visits [OR= 1.84, p< 0.001]. Patients with low EAR had higher odds of revision arthroscopy [OR= 1.42, p= 0.005] and THA conversion [OR= 1.58, p= 0.002] compared to those with high EAR.

CONCLUSION

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.

Modern Hip Arthroscopy for FAIS May Delay the Natural History of Osteoarthritis in 25% of Patients: A 12-Year Follow-up Analysis

BACKGROUND

Little is known about the effect of modern hip arthroscopy on the natural history of femoroacetabular impingement syndrome (FAIS) with respect to joint preservation.

PURPOSE

To (1) characterize the natural history of FAIS and (2) understand the effect of modern hip arthroscopy by radiographically comparing the hips of patients who underwent only unilateral primary hip arthroscopy with a minimum follow-up of 10 years.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Between 2010 and 2012, 619 consecutive patients were reviewed from the practice of a single fellowship-trained hip arthroscopic surgeon. Inclusion criteria were FAIS, bilateral radiographic findings of femoroacetabular impingement, primary unilateral hip arthroscopy (labral repair, femoroplasty, or capsular closure), and minimum 10-year follow-up. The preoperative and minimum 10-year postoperative radiographs of patients were evaluated at each time point. Both operative and nonoperative hips were graded using the Tönnis classification or the presence of hip arthroplasty by 2 independent reviewers. Subgroup analyses were performed.

RESULTS

A total of 200 hips from 100 patients were evaluated at a mean follow-up of 12.0 years. Preoperatively, 98% and 99% of operative and nonoperative hips were evaluated as Tönnis grades 0 and 1, respectively; 5% of nonoperative hips had worse Tönnis grades than operative hips. The nonoperative hip advanced to a worse Tönnis grade in 48% (48/100) of cases compared with 28% (28/100) among operative hips. At follow-up, Tönnis grades between hips were equal in 70% (70/100) of the cases, the operative hip had a better grade 25% (25/100) of the time, and the nonoperative hip had a better grade 5% (5/100) of the time. Modern hip arthroscopy was associated with a relative risk reduction of 42% in osteoarthritis progression. Impingement with borderline dysplasia, age, preoperative Tönnis grade, and alpha angle >65° were key risk factors in the radiographic progression of osteoarthritis.

CONCLUSION

Although the majority of patients (70%) undergoing hip arthroscopy for FAIS did not experience differences between operative and nonoperative hips in terms of the radiographic progression of osteoarthritis, the natural history may be favorably altered for 25% of patients whose Tönnis grade was better after undergoing arthroscopic correction. Modern hip arthroscopy indications and techniques represent a valid joint-preservation procedure conferring a relative risk reduction of 42% in the progression of osteoarthritis. Arthroscopy for mixed patterns of impingement and instability were the fastest to degenerate.

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.

Patients With Lateral and Anterolateral Cam Morphology Have Greater Deformities Versus Typical Anterolateral Deformity Alone but No Differences in Postoperative Outcomes: A Propensity-Matched Analysis at Minimum 5-Year Follow-Up

PURPOSE

To compare pre- and postoperative findings between patients undergoing hip arthroscopy for femoroacetabular impingement syndrome with lateral impingement versus those without lateral impingement METHODS: Patients who underwent primary hip arthroscopy for femoroacetabular impingement syndrome between 2012 and 2017 with minimum 5-year follow-up were included. Alpha angle (AA) was measured on preoperative anteroposterior (AP) and 90° Dunn radiographs. Patients with AA >60° on Dunn view but not AP view (no lateral impingement) were propensity matched by sex, age, and body mass index in a 1:3 ratio to patients with AA >60° on both views (lateral impingement). Demographic characteristics, radiographic and intraoperative findings, reoperation rates, and patient-reported outcomes (PROs) were compared between groups. Categorical variables were compared using the Fisher exact testing and continuous variable using 2-tailed Student t tests.

RESULTS

Sixty patients with lateral impingement (65.0% female, age: 35.3 ± 13.0 years) were matched to 180 patients without lateral impingement (65.0% female, age: 34.7 ± 12.5 years, P ≥ .279). Patients with lateral impingement had larger preoperative AAs on both Dunn (71.0° ± 8.8° vs 67.6° ± 6.1°, P = .001) and AP radiographs (79.0° ± 12.1° vs 48.2° ± 6.5°, P < .001). However, there were no differences in postoperative AAs on either view (Dunn: 39.0° ± 6.1° vs 40.5° ± 5.3°, AP: 45.8° ± 9.0° vs 44.9° ± 7.0°, P ≥ .074). Labral tears began more superiorly in patients with lateral impingement (12:00 ± 0:49 vs 12:17 ± 0:41, P = .030), and they demonstrated greater rates of acetabular and femoral cartilage damage (P = .030 for both); however, there were no differences in PROs or reoperation rates between the groups at 5-year follow-up.

CONCLUSIONS

Although cam deformities located laterally and anterolaterally are larger than those located anterolaterally alone, both can be resected adequately, resulting in similar postoperative radiographic measurements, PROs, and survivorship.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Effect of cam resection depth on clinical outcomes after primary hip arthroscopy

BACKGROUND

The amount of resection or the starting point of the resection on the femoral head for cam lesions in femoroacetabular impingement (FAI) is controversial.

AIM

The purpose of this study was to study the effect of postoperative resection depth, and resection arc ratio of cam lesion on the frequency of achieving substantial clinical benefit (SCB), patient acceptable state (PASS) in modified Harris Hip Score (mHHS) and Hip Outcome Score Activity of Daily Living (HOSADL), 2 years postoperatively.

PATIENTS AND METHODS

All patients who underwent first-time hip arthroscopy for FAI with a 2-year follow-up were included in this study. Patient-reported outcomes included the mHHS, HOSADL, and visual analogue scale for pain (Pain VAS). Radiological parameters such as alpha angletraditional (αT), alpha anglecartilage (αC), resection arc ratio (% alpha anglecartilage-alpha angletraditional/360°), resection depth (''D''mm) and resection depth ratio 'D%' (D/femoral head diameter %) were measured using the 45° Dunn view.

RESULTS

We identified 26 patients (27 hips) with 2-year follow-up. There were 10 female and 16 male patients. The mean age of the patients was 33 ± 12 years.Higher frequency of achieving SCB threshold for mHHS was related to labrum repair (73% vs. debridement '27%' p = 0.03), lower preoperative αT (64° vs. 76°, p = 0.04), lower preoperative mHHS (54 vs. 81, p < 0.001) and higher preoperative VAS scores (8 vs. 7, p = 0.02). Higher frequency of reaching PASS threshold for mHHS was associated with lower αC (82°vs. 92° p:0.02), lower RA (8% vs. 11%, p = 0.03), lower D (2.8 mm vs. 4.5 mm p:0.03), lower D% (4.7% vs. 8.4% p = 0.04) and higher postoperative mHHS (97 vs. 82 p < 0.001).

CONCLUSIONS

A higher frequency of achieving SCB for HOSADL was related to lower D% (5% vs. 10.5%, p = 0.04).Cam resection depth affects the frequency of achieving clinically meaningful scores and resection depth less than 6% of the femoral head diameter seems to be appropriate for optimal results. The starting point of resection on head cartilage needs to be <90° when alpha angle is used for reference.

Injections prior to hip arthroscopy are associated with increased risk of repeat hip arthroscopy at 1 and 5 years

INTRODUCTION

Previous studies have shown that intra-articular hip injections prior to hip arthroscopy (HA) can be a helpful diagnostic tool. However, local anesthetic and corticosteroid injections can be chondrotoxic and corticosteroid injections have been shown to increase the risk of infection during subsequent surgical intervention. The purpose of this study was to evaluate whether preoperative injections adversely affect outcomes of HA using a national database.

MATERIALS AND METHODS

The TriNetX database was retrospectively queried. Patients undergoing HA for femoroacetabular impingement with at least 1 year of claims runout were included in the analysis. Patients were grouped by whether they had a hip injection within 1 year prior to HA. The rates of repeat HA, total hip arthroplasty (THA), infection, osteonecrosis, and new onset hip OA at 1- and 5-years postoperatively were compared between groups. Statistical significance was assessed at α = 0.05.

RESULTS

6511 HA patients with previous injection and 1178 HA patients without previous injection were included. Patients with a previous injection were overall younger (32.3 vs. 34.7 years, p < 0.001), more likely to be female (69 vs. 48%, p < 0.001) and had a higher BMI (26.3 vs. 25.7 kg/m2, p = 0.043). At 1 and 5-years postoperatively, patients with any injection were 1.43 (p < 0.001) and 1.89 (p < 0.001) times more likely to undergo repeat HA, respectively. At 1 and 5-years postoperatively, patients who underwent a corticosteroid injection were 2.29 (p < 0.001) and 1.89 (p < 0.001) times more likely to undergo repeat HA than patients with local anesthetic injection only and 1.56 (p < 0.001) and 2.08 (p < 0.001) times more likely to undergo repeat HA than patients with no injection.

CONCLUSIONS

Intraarticular hip injections prior to hip arthroscopy, particularly corticosteroid injections, are associated with increased risk of repeat hip arthroscopy at 1 and 5 years. Additional studies are needed to elucidate this risk.

Assessment of Risk Factors and Rate of Conversion to Total Hip Arthroplasty Within 2 Years After Hip Arthroscopy Utilizing a Large Database of Commercially Insured Patients in the United States

Background

The conversion rate of hip arthroscopy (HA) to total hip arthroplasty (THA) has been reported to be as high as 10%. Despite identifying factors that increase the risk of conversion, current studies do not stratify patients by type of arthroscopic procedure.

Purpose/Hypothesis

To analyze the rate and predictors of conversion to THA within 2 years after HA. It was hypothesized that osteoarthritis (OA) and increased patient age would negatively affect the survivorship of HA.

Study Design

Cohort study; Evidence level, 3.

Methods

The IBM MarketScan database was utilized to identify patients who underwent HA and converted to THA within 2 years at inpatient and outpatient facilities between 2013 and 2017. Patients were split into 3 procedure cohorts as follows: (1) femoroacetabular osteoplasty (FAO), which included treatment for femoroacetabular impingement; (2) isolated debridement; and (3) isolated labral repair. Cohort characteristics were compared using standardized differences. Conversion rates between the 3 cohorts were compared using chi-square tests. The relationship between age and conversion was assessed using linear regression. Predictors of conversion were analyzed using multivariable logistic regression. The median time to conversion was estimated using Kaplan-Meier tests.

Results

A total of 5048 patients were identified, and the rates of conversion to THA were 12.86% for isolated debridement, 8.67% for isolated labral repair, and 6.76% for FAO (standardized difference, 0.138). The isolated labral repair cohort had the shortest median time to conversion (isolated labral repair, 10.88 months; isolated debridement, 10.98 months; and FAO, 11.9 months [P = .034). For patients >50 years, isolated debridement had the highest rate of conversion at 18.8%. The conversion rate increased linearly with age. Factors that increased the odds of conversion to THA were OA, having an isolated debridement procedure, and older patient age (P < .05).

Conclusion

Older patients and those with preexisting OA of the hip were at a significantly increased risk of failing HA and requiring a total hip replacement within 2 years of the index procedure. Younger patients were at low risk of requiring a conversion procedure no matter which arthroscopic procedure was performed.

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.

Non-operative Management and Outcomes of Femoroacetabular Impingement Syndrome

PURPOSE

To serve as a guide for non-operative physicians in the management of femoroacetabular impingement syndrome and provide an algorithm as to when to refer patients for potential surgical management.

RECENT FINDINGS

Supervised physical therapy programs that focus on active strengthening and core strengthening are more effective than unsupervised, passive, and non-core-focused programs. There is promising evidence for the use of intra-articular hyaluronic acid and PRP as adjunct treatment options. Recent systematic reviews and meta-analyses have found that in young active patients, hip arthroscopy demonstrates improved short-term outcomes over physical therapy. The decision for the management of FAIS is complex and should be specific to each patient. Consideration of the patient's age, timing to return to sport, longevity of treatment, hip morphology, and degree of cartilage degeneration is required to make an informed decision in the treatment of these patients.

Progression of Osteoarthritis at Long-term Follow-up in Patients Treated for Symptomatic Femoroacetabular Impingement With Hip Arthroscopy Compared With Nonsurgically Treated Patients

BACKGROUND

Femoroacetabular impingement (FAI) is a common cause of hip pain, especially in young patients. When left untreated, it has been demonstrated to be a risk factor for the onset or progression of osteoarthritis (OA) and has been identified as one of the main contributors leading to the need for total hip arthroplasty (THA) at a young age. While the short-term therapeutic potential of hip arthroscopy is widely recognized, little is known regarding its potential mid- to long-term preventive effect on the progression of hip OA.

PURPOSE

To (1) report clinical outcomes of arthroscopically treated FAI syndrome with a minimum 5-year follow-up and compare the results to a cohort with FAI treated nonsurgically and (2) determine the influence of hip arthroscopy on the onset and progression of hip OA in patients diagnosed with FAI.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who had hip pain and were diagnosed with FAI were included. Exclusion criteria were (1) previous or concomitant hip surgery, (2) <5 years of follow-up, and (3) insufficient radiographs. Patients treated with hip arthroscopy were compared with a cohort of patients with FAI who were treated nonsurgically. Kaplan-Meier estimates of failure (defined as conversion to THA) were performed. Bivariate analysis and Cox regression were used to identify factors associated with inferior clinical and radiographic outcomes.

RESULTS

A total of 957 patients (650 female, 307 male; 1114 hips) (mean age, 28.03 ± 8.9 years [range, 6.5-41.0 years]) with FAI were included. A total of 132 hips underwent hip arthroscopy and 982 hips were nonoperatively treated. The mean follow-up was 12.5 ± 4.7 years (range, 5.0-23.4 years). At the final follow-up, the rate of OA progression was 26.5% in the operative group and 35.2% in the nonoperative cohort (P < .01). Conversion to THA was performed in 6.8% of the surgical patients and 10.5% of the initially nonsurgical patients (P = .19). Additionally, there was no significant difference in the risk of failure between the operatively and nonoperatively treated patients. Male sex, increased age at initial diagnosis, presence of cam morphology, and increased initial Tönnis grade were risk factors for failure (male sex: hazard ratio [HR], 2.3; P < .01; per year of increased age: HR, 1.1; P < .01; presence of cam: HR, 3.5; P < .01; per Tönnis grade: HR, 4.0; P < .01).

CONCLUSION

At a mean follow-up of nearly 13 years, 7% of patients of the surgical group experienced progression to THA, compared with 11% of the nonoperative control group. While most of the operative group showed little to no OA at final follow-up, moderate OA (Tönnis grade 2) was present in 12% of the cohort compared with 22% of nonsurgical patients. Increased age at diagnosis, male sex, presence of a cam morphology, and presence of initial arthritic joint changes were found to be risk factors for failure. The results of this study demonstrated evidence for a preventive effect of hip arthroscopy on the development and progression of OA in young patients with FAI at mid- to long-term follow-up.

Postoperative alpha angle seems to be important for the achievement of clinical significance at a minimum 5-year follow-up after primary hip arthroscopy

The purpose of the present study was to clarify whether there is an association of postoperative alpha value with functional scores or progression of osteoarthritis at X-rays at the midterm after arthroscopic treatment of femoroacetabular impingement (FAI) syndrome with femoral osteoplasty, labral repair or debridement and rim trimming. A retrospective review of prospectively gathered data from 2013 to 2017 was performed. All patients who underwent first-time unilateral hip arthroscopy for FAI resection with 5-year follow-up were included. Patient-reported outcomes included the modified Harris Hip Score (mHHS) and Visual Analog Scale for Pain (Pain VAS). The progression of osteoarthritis (Tönnis grade) and radiological parameters (alpha angle, lateral center-edge angle [LCEA] and head-neck offset) were evaluated. A receiver operating characteristic (ROC) analysis was used to evaluate the correlation between significant variables and achievement of patient-acceptable symptomatic state (PASS) and degree of osteoarthritis. We identified 52 patients with a minimum 5-year follow-up (average, 6.7 years). The average patient age was 33.9 ± 11.5 years. There were 19 (36.5%) female patients. The mHHS improved from 60.1 ± 13.4 before surgery to 86.8 ± 14 after surgery (P < 0.001). The Pain VAS decreased from 6.21 before surgery to 2 after surgery (P < 0.001). Overall, 69% achieved the PASS for mHHS. The ROC curve for postoperative alpha angle demonstrated acceptable discrimination between patients achieving a fifth-year PASS value and those who did not have an area under the curve of 0.72. Patients having a postoperative alpha angle of ≤48.3° achieved the fifth-year PASS value at a significantly higher rate than patients having a postoperative alpha angle of >48.3° (P = 0.002). The postoperative alpha angle is a predictor of the achievement of the fifth-year PASS value for the mHHS. A threshold of ≤48.3° had a sensitivity of 0.75 and a specificity of 0.69 to predict positivity. Level of evidence IV.

Use and Effectiveness of Physical Therapy After Hip Arthroscopy for Femoroacetabular Impingement

BACKGROUND

Limited literature exists regarding how postoperative physical therapy (PT) may affect outcomes in patients with femoroacetabular impingement syndrome (FAIS) undergoing hip arthroscopy. Additionally, it is unknown how PT measures relate to traditional orthopaedic patient-reported outcomes (PROs).

PURPOSE

To evaluate how the duration of PT may correlate with outcomes in patients with FAIS using both the Lower Extremity Functional Scale (LEFS) and standard orthopaedic PRO measures.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients from a single institution who underwent primary hip arthroscopy for FAIS between 2013 and 2016 were identified. Patients with a minimum 2-year follow-up and fully documented PT notes were included and stratified into 3 cohorts based on timing of PT discharge: 0 to 3 months, 3 to 6 months, and 6 to 12 months. Predictive regression models were developed to analyze the rate of improvement (ROI) in LEFS score as it relates to (1) postoperative day (POD) and (2) postoperative PT session number. Two-year PROs were collected, correlated with LEFS scores, and compared among cohorts.

RESULTS

A total of 95 patients were included (mean ± SD age, 34.6 ± 11.7 years; range, 14-55 years). Mean LEFS scores increased significantly from the initial score at 6 weeks, 3 months, and the time of PT discharge (P < .01 for all). The predicted ROI in LEFS score was 3.39% per PT session for sessions 0 to 13, 1.43% for sessions 14 to 27, and 0.37% for sessions 28 to 40. Patients who underwent 3 to 6 months of PT had significantly better Hip Outcome Score (HOS) relative to the 0- to 3-month cohort and significantly better visual analog scale (VAS) scores for satisfaction relative to the 6- to 12-month cohort. The predicted ROI in LEFS score was 0.96% per day from POD 0 to 45, 0.22% from POD 46 to 139, and 0.03% after POD 139. Moderate correlations were seen between LEFS score at the time of discharge and all 2-year PROs as follows: HOS Activities of Daily Living subscale (r = 0.488), HOS Sports-Specific subscale (r = 0.500), modified Harris Hip Score (r = 0.465), 12-item International Hip Outcome Tool (r = 0.494), VAS pain score (r = -0.346), and VAS satisfaction score (r = 0.459).

CONCLUSION

Patients undergoing hip arthroscopy for FAIS derived substantial benefit from each PT visit during their first 13 PT sessions and then a smaller, yet still meaningful benefit from sessions 13 through 27. After session 40, or approximately 4.5 to 5 months, patients no longer benefited from additional PT sessions. Based on PRO scores, patients discharged from PT between 3 and 6 months had the best 2-year outcomes. LEFS score had moderate correlation with orthopaedic PRO scores.

Patients Maintain Clinically Significant Outcomes at 5-Year Follow-Up after Hip Arthroscopy for Femoroacetabular Impingement Syndrome: A Systematic Review

PURPOSE

To assess 5-year outcomes and survival rate of hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS) and to determine achievement rates of clinically significant outcomes.

METHODS

Three databases were searched around the following terms: hip arthroscopy, FAIS, and 5-year follow-up. Articles available in English, presenting original data, and reporting minimum 5-year follow-up after primary HA using either patient reported outcomes (PROs) or conversion to total hip arthroplasty (THA) and/or revision surgery were included. Quality assessment was completed using MINORS assessment, and relative agreement was calculated using Cohen's kappa.

RESULTS

Fifteen articles were included. MINORS assessment ranged from 11-22, with excellent (k=0.842) inter-rater reliability between reviewers. 2080 patients were included at a follow-up range of 60.0-84 months. Labral repair was the most commonly performed procedure (range: 8.0%-100%). All studies included PROs and all reported statistically significant improvement (p<0.05) at the 5-year timepoint. The most frequent PRO reported was modified Harris Hip Score (mHHS) (n=8). Nine studies reported on clinically significant outcome achievement, with mHHS being the most common (n=8). The rate of achieving minimal clinically important difference (MCID) ranged from 64-100%, patient-acceptable symptomatic state (PASS) ranged from 45-87.4%, and substantial clinical benefit (SCB) ranged from 35.3-66%. Conversion to THA and revision surgery varied across studies, with ranges of 0.0%-17.9% (duration: 28.8-87.1 months) and 1.3%-26.7% (duration: 14.8-83.7 months), respectively. The most common definition of failure was conversion to THA or revision (n=7). Increased age (n=5) and greater joint degeneration (n=4) were the most common predictors of clinical failure.

CONCLUSIONS

Patients undergoing primary hip arthroscopy for FAIS demonstrate significant improvement at 5-year follow-up, with maintained rates of achievement of MCID, PASS, and SCB. Survival rate of HA at 5-years is overall high, with ranges of 0.0-17.9% and 1.3-26.7% % conversion to THA or revision surgery, respectively. Across studies, increased age and greater joint degeneration were the most common cited predictors of clinical failure.

The HAR-index: a reliable method for evaluating the risk of total hip arthroplasty conversion after hip arthroscopy for femoroacetabular impingement

PURPOSE

Hip arthroscopy is a growing technique in the treatment of femoroacetabular impingement (FAI), but can sometimes lead to unsatisfactory results such as the early conversion to total hip arthroplasty (THA). The purpose of this study is to describe a new tool for assessing the preoperative risk of THA conversion after hip arthroscopy in patients with FAI.

METHODS

This study is a retrospective analysis of a prospective cohort of 584 patients with FAI who underwent hip arthroscopy at a single centre with a minimum 2 years follow-up. The preoperative variables of these patients were analysed to calculate the risk of each variable for THA. By selecting variables with an area under the receiver operating characteristic (ROC) curve greater than 0.7, a calculator was created to provide a risk index for each patient.

RESULTS

Four variables (age, body mass index, Tönnis score and ALAD) were associated with an increased risk of THA conversion. The optimal cut-off points for each variable were determined, and a risk index was created. The Hip-Arthroplasty-Risk Index (HAR-Index) is a 0-4 points scale obtained from four binary scores of 0 or 1 depending on whether the cut-off point for each variable was reached or not. The increased risk of THA for each HAR-Index value was 1.1%, 6.2%, 17.9%, 55.1% and 79.3% respectively. The HAR-Index showed a very good predictive capacity with an area under the ROC curve of 0.89.

CONCLUSION

The HAR-Index is a simple and practical tool for practitioners to make more informed decisions about performing hip arthroscopy in patients with FAI. With a very good predictive capacity, the HAR-Index can help to reduce the rate of conversion to THA.

LEVEL OF EVIDENCE

Level III.

Do patients with femoroacetabular impingement syndrome who undergo hip arthroscopy display improved alpha angle (magnetic resonance imaging) and radiographic hip morphology?

AIMS

To compare (a) the change in radiological bony morphology between participants with femoroacetabular impingement (FAI) syndrome who underwent arthroscopic hip surgery compared to physiotherapist-led non-surgical care and (b) the change in radiological bony morphology between participants with FAI syndrome who underwent arthroscopic hip surgery involving cam resection or acetabular rim trimming or combined cam resection and acetabular rim trimming.

METHODS

Maximum alpha angle measurements on magnetic resonance imaging and Hip2 Norm standardized hip measurements on radiographs were recorded at baseline and at 12 months postoperatively. One-way analysis of covariance and independent T tests were conducted between participants who underwent arthroscopic hip surgery and physiotherapist-led non-surgical care. Independent T tests and analysis of variance were conducted between participants who underwent the 3 different arthroscopic hip procedures.

RESULTS

Arthroscopic hip surgery resulted in significant improvements to mean alpha angle measurements (decreased from 70.8° to 62.1°) (P value < .001, 95% CI -11.776, -4.772), lateral center edge angle (LCEA) (P value = .030, 95% CI -3.403, -0.180) and extrusion index (P value = 0.002, 95% CI 0.882, 3.968) compared to physiotherapist-led management. Mean maximum 1-year postoperative alpha angle was 59.0° (P value = .003, 95% CI 4.845, 18.768) for participants who underwent isolated cam resection. Measurements comparing the 3 different arthroscopic hip procedures only differed in total femoral head coverage (F[2,37] = 3.470, P = .042).

CONCLUSION

Arthroscopic hip surgery resulted in statistically significant improvements to LCEA, extrusion index and alpha angle as compared to physiotherapist-led management. Measured outcomes between participants who underwent cam resection and/or acetabular rim trimming only differed in total femoral head coverage.

Lateral to Medial Joint Space Ratio is Predictive of Survivorship After Primary Hip Arthroscopy

PURPOSE

To assess whether preoperative joint space measures would be predictive of survivorship in patients undergoing hip arthroscopy (HA) for femoroacetabular impingement (FAI).

METHODS

Data on consecutive patients who underwent hip arthroscopy between February 2008 and February 2018 were retrospectively reviewed. To be eligible for final analysis, patients were required to have preoperative radiographs for joint space measurements and data indicating conversion to a total hip arthroplasty (THA), hip resurfacing, or neither; at a minimum of 2 years after primary hip arthroscopy. Survivorship following HA was defined as remaining conversion free and served as the primary outcome. A multivariate logistic regression analysis and receiver operator curve (ROC) were used to evaluate the correlation between joint space measurements and survivorship following HA.

RESULTS

A total of 1,885 primary arthroscopy cases were included in this study. The multivariate regression analysis found preoperative lateral-to-medial joint space ratio (L/M ratio) to be the strongest predictive factor of survivorship after primary hip arthroscopy (OR = 2.084, CI_95% = 1.239-3.503; P = .006). The ROC curve for the model demonstrated acceptable discrimination with an area under the curve (AUC) of 0.792. Patients with an L/M ratio ≥0.75 had a survivorship rate of 91.7% compared to a rate of 75% for patients with an L/M ratio <0.75 (OR: 3.68).

CONCLUSIONS

This study found that, of the factors evaluated in this study, the most significant factor in predicting survivorship at 2 years after undergoing primary hip arthroscopy was a larger lateral-to-medial joint space ratio. This may suggest an initiation of primary arthritis at the edge-loading area of the lateral acetabulum. LEVEL OF EVIDENCE: III, retrospective comparative observation study.

Moderators, Mediators, and Prognostic Indicators of Treatment With Hip Arthroscopy or Physical Therapy for Femoroacetabular Impingement Syndrome: Secondary Analyses From the Australian FASHIoN Trial

BACKGROUND

Although randomized controlled trials comparing hip arthroscopy with physical therapy for the treatment of femoroacetabular impingement (FAI) syndrome have emerged, no studies have investigated potential moderators or mediators of change in hip-related quality of life.

PURPOSE

To explore potential moderators, mediators, and prognostic indicators of the effect of hip arthroscopy and physical therapy on change in 33-item international Hip Outcome Tool (iHOT-33) score for FAI syndrome.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Overall, 99 participants were recruited from the clinics of orthopaedic surgeons and randomly allocated to treatment with hip arthroscopy or physical therapy. Change in iHOT-33 score from baseline to 12 months was the dependent outcome for analyses of moderators, mediators, and prognostic indicators. Variables investigated as potential moderators/prognostic indicators were demographic variables, symptom duration, alpha angle, lateral center-edge angle (LCEA), Hip Osteoarthritis MRI Scoring System (HOAMS) for selected magnetic resonance imaging (MRI) features, and delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) score. Potential mediators investigated were change in chosen bony morphology measures, HOAMS, and dGEMRIC score from baseline to 12 months. For hip arthroscopy, intraoperative procedures performed (femoral ostectomy ± acetabular ostectomy ± labral repair ± ligamentum teres debridement) and quality of surgery graded by a blinded surgical review panel were investigated for potential association with iHOT-33 change. For physical therapy, fidelity to the physical therapy program was investigated for potential association with iHOT-33 change.

RESULTS

A total of 81 participants were included in the final moderator/prognostic indicator analysis and 85 participants in the final mediator analysis after exclusion of those with missing data. No significant moderators or mediators of change in iHOT-33 score from baseline to 12 months were identified. Patients with smaller baseline LCEA (β = -0.82; P = .034), access to private health care (β = 12.91; P = .013), and worse baseline iHOT-33 score (β = -0.48; P < .001) had greater iHOT-33 improvement from baseline to 12 months, irrespective of treatment allocation, and thus were prognostic indicators of treatment response. Unsatisfactory treatment fidelity was associated with worse treatment response (β = -24.27; P = .013) for physical therapy. The quality of surgery and procedures performed were not associated with iHOT-33 change for hip arthroscopy (P = .460-.665 and P = .096-.824, respectively).

CONCLUSION

No moderators or mediators of change in hip-related quality of life were identified for treatment of FAI syndrome with hip arthroscopy or physical therapy in these exploratory analyses. Patients who accessed the Australian private health care system, had smaller LCEAs, and had worse baseline iHOT-33 scores, experienced greater iHOT-33 improvement, irrespective of treatment allocation.

Limited clinical utility of a machine learning revision prediction model based on a national hip arthroscopy registry

PURPOSE

Accurate prediction of outcome following hip arthroscopy is challenging and machine learning has the potential to improve our predictive capability. The purpose of this study was to determine if machine learning analysis of the Danish Hip Arthroscopy Registry (DHAR) can develop a clinically meaningful calculator for predicting the probability of a patient undergoing subsequent revision surgery following primary hip arthroscopy.

METHODS

Machine learning analysis was performed on the DHAR. The primary outcome for the models was probability of revision hip arthroscopy within 1, 2, and/or 5 years after primary hip arthroscopy. Data were split randomly into training (75%) and test (25%) sets. Four models intended for these types of data were tested: Cox elastic net, random survival forest, gradient boosted regression (GBM), and super learner. These four models represent a range of approaches to statistical details like variable selection and model complexity. Model performance was assessed by calculating calibration and area under the curve (AUC). Analysis was performed using only variables available in the pre-operative clinical setting and then repeated to compare model performance using all variables available in the registry.

RESULTS

In total, 5581 patients were included for analysis. Average follow-up time or time-to-revision was 4.25 years (± 2.51) years and overall revision rate was 11%. All four models were generally well calibrated and demonstrated concordance in the moderate range when restricted to only pre-operative variables (0.62-0.67), and when considering all variables available in the registry (0.63-0.66). The 95% confidence intervals for model concordance were wide for both analyses, ranging from a low of 0.53 to a high of 0.75, indicating uncertainty about the true accuracy of the models.

CONCLUSION

The association between pre-surgical factors and outcome following hip arthroscopy is complex. Machine learning analysis of the DHAR produced a model capable of predicting revision surgery risk following primary hip arthroscopy that demonstrated moderate accuracy but likely limited clinical usefulness. Prediction accuracy would benefit from enhanced data quality within the registry and this preliminary study holds promise for future model generation as the DHAR matures. Ongoing collection of high-quality data by the DHAR should enable improved patient-specific outcome prediction that is generalisable across the population.

LEVEL OF EVIDENCE

Level III.

Hip Arthroscopy Results in Similar Short-Term Function Compared to THA in Patients of Similar Demographic Profiles

Purpose

To review short-term functional outcomes in patients who underwent hip arthroscopy and to compare their outcomes to those of a demographically similar cohort who underwent total hip arthroplasty (THA).

Methods

Data were prospectively collected and retrospectively reviewed for patients undergoing hip arthroscopy (SCOPE) between April 2008 and October 2015. SCOPE patients were included if they were ≥35 years, had preoperative and postoperative 2-year follow-up, and had no prior hip condition or ipsilateral hip surgery. SCOPE patients were matched 1:1 to a demographically similar cohort of patients who underwent THA at our institution. Matching criteria included similar age (within 5 years), gender, and body mass index (within 5). SCOPE patients were assessed with modified Harris Hip Score (mHHS), non-arthritic hip score, and visual analogue scale (VAS). THA patients were assessed with mHHS, forgotten joint score, and VAS.

Results

Sixty-seven patients were included in each cohort. Patients who underwent hip arthroscopy for management of labral tears achieved nearly equivalent mHHS, Health Survey Short Form (SF-12) Mental, SF-12 Physical, Veterans RAND 12 Item Health Survey (VR-12) Mental, VR-12 Physical scores at latest follow-up compared to demographically similar patients who underwent THA. There was no significant difference in mHHS scores (SCOPE = 82.9 ± 16.4 vs THA = 87.3 ± 15, P = .095) between the 2 group groups. In addition, average patient satisfaction on a 10-point scale was 8.1 for the SCOPE cohort and 8.8 for the THA cohort (P = .052).

Conclusions

Our results show that hip arthroscopy, when performed in patients with the appropriate indications, can lead to comparably excellent outcomes as total hip arthroplasty with significant pain relief at short term follow-up.

Level of Evidence

Level III, retrospective cohort study.

Biomechanical Evaluation of 4 Suture Techniques for Hip Capsular Closure

Background:

The most reliable suture technique for capsular closure after a capsulotomy remains unknown.

Purpose:

To determine which suture technique best restores native stability after a 5-cm interportal capsulotomy.

Study Design:

Controlled laboratory study.

Methods:

Ten human cadaveric hip specimens were tested using a 6-degrees-of-freedom robotic arm in 7 states: intact, capsular laxity, 5-cm capsulotomy, standard suture, shoelace, double shoelace, and Quebec City slider (QCS). Rotational range of motion (ROM) was measured across 9 tests: flexion, extension, abduction, abduction at 45° of flexion, adduction, external rotation, internal rotation, anterior impingement, and log roll. Distraction (ie, femoral head translation [FHT]) was measured across a range of flexion and abduction angles.

Results:

When compared with the native state, the 5-cm capsulotomy state showed the largest laxity increases on all tests, specifically in external rotation ROM (+13.4°), extension ROM (+11.5°), and distraction FHT (+4.5 mm) (P < .001 for all). The standard suture technique was not significantly different from the 5-cm capsulotomy on any test and demonstrated significantly more flexion ROM than the double shoelace suture (+1.41°; P = .049) and more extension ROM (+5.51°; P = .014) and external rotation ROM (+6.03°; P = .021) than the QCS. The standard suture also resulted in significantly higher distraction FHT as compared with the shoelace suture (+1.0 mm; P = .005), double shoelace suture (+1.4 mm; P < .001), and QCS (+1.1 mm; P = .003). The shoelace, double shoelace, and QCS techniques significantly reduced hip laxity when compared with the 5-cm capsulotomy state, specifically in external rotation ROM (respectively, –8.1°, –7.8°, and –10.2°), extension ROM (–6.3°, –7.3°, and –8.1°), and distraction FHT (–1.8, –2.2, and –1.9 mm) (P ≤ .003 for all). These 3 techniques restored native stability (no significant difference from intact) on some but not all tests, and no significant differences were observed among them on any test.

Conclusion:

Hip capsule closure with the standard suture technique did not prevent postoperative hip instability after a 5-cm capsulotomy, and 3 suture techniques were found to be preferable; however, none perfectly restored native stability at time zero.

Clinical Relevance:

The shoelace, double shoelace, and QCS suture techniques are recommended when closing the hip capsule.

Effect of Osteochondroplasty on Time to Reoperation After Arthroscopic Management of Femoroacetabular Impingement: Analysis of a Randomized Controlled Trial

Background:

A subset of patients with femoroacetabular impingement (FAI) fail arthroscopic management. It is not clear which patients will fail surgical management; however, several surgical and patient factors, such as type of procedure and age, are thought to be important predictors.

Purpose:

This time-to-event analysis with a 27-month follow-up analysis compared the effect of (1) arthroscopic osteochondroplasty with or without labral repair versus (2) arthroscopic lavage with or without labral repair on the time to reoperation in adults aged 18 to 50 years with FAI.

Study Design:

Randomized controlled trial; Level of evidence, 1.

Methods:

Eligible participants had been randomized in a previous study trial to a treatment of arthroscopic osteochondroplasty or arthroscopic lavage with or without labral repair. Using the comprehensive data set from the Multinational Femoroacetabular Impingement Randomized controlled Trial, all reoperations until 27 months after surgery were identified. The analysis was conducted using a Cox proportional hazards model, with percentage of patients with a reoperation evaluated in a time-to-event analysis as the outcome. The independent variable was the procedure, with age and impingement subtype explored as potential covariates. The effects from the Cox model were expressed as the hazard ratio (HR). All tests were 2-sided, with an alpha level of .05.

Results:

A total of 108 patients in the osteochondroplasty group and 106 patients in the lavage group were included. The mean age of the patients included in the study was 36 ± 8.5 years. Overall, 27 incident reoperations were identified within the 27-month follow-up, with an incidence rate of 6 per 100 person-years. Within the osteochondroplasty group, 8 incident reoperations were identified (incidence rate, 3.4 per 100 person-years), while within the lavage group, 19 incident reoperations were identified (incidence rate, 8.7 per 100 person-years). The hazard of reoperation for patients undergoing osteochondroplasty was 40% of that of patients undergoing lavage (HR, 0.40 [95% CI, 0.17-0.91] P = .029).

Conclusion:

This study demonstrated that for adults between the ages of 18 and 50 years with FAI, arthroscopic osteochondroplasty was associated with a 2.5-fold decrease in the hazard of reoperation at any point in time compared with arthroscopic lavage.

Registration:

NCT01623843 (ClinicalTrials.gov identifier).

Revision Surgery and Progression to Total Hip Arthroplasty After Surgical Correction of Femoroacetabular Impingement: A Systematic Review

BACKGROUND

Femoroacetabular impingement (FAI) is a major cause of hip pain in young adults and athletes. Surgical treatment of FAI is recommended in cases of failed nonoperative treatment that have the typical clinical and radiographic findings. At present, the role of risk factors for revision surgery and progression to total hip arthroplasty (THA) in patients with FAI is still unclear.

PURPOSE

To investigate the possible association between (1) rate of revision and progression to THA and (2) patient characteristics, type of lesion, family history of hip disease, type of intervention, radiographic parameters, physical examination, and pre- and postoperative scores.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

The present systematic review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. In October 2020, the main online databases were accessed. All articles concerning surgical correction for selected patients with FAI were accessed. Patient characteristics, type of intervention, radiographic parameters, physical examination, and pre- and postoperative scores were assessed. The outcomes of interest were the possible association between these variables and the rate of revision and subsequent progression to THA using a multivariate analysis through the Pearson product-moment correlation coefficient.

RESULTS

Data from 99 studies (9357 procedures) were collected. The median follow-up was 30.9 months (interquartile range, 24.0-45.0). The mean ± SD age was 33.4 ± 9.3 years; mean body mass index (BMI), 24.8 ± 4.8; percentage right side, 55.8% ± 8.0%; and percentage female sex, 47.5% ± 20.4%. The overall rate of revision was 5.29% (351 of 6641 patients), while the rate of subsequent progression to THA was 3.78% (263 of 6966 patients). Labral debridement (P < .0001), preoperative acetabular index (P = .01), and BMI (P = .03) all showed evidence of a statistically positive association with increased rates of THA. No other statistically significant associations were found between patient characteristics, type of lesion, family history of hip disease, type of intervention, radiographic parameters, physical examination, or pre- and postoperative scores and the rate of revision and/or progression to THA.

CONCLUSION

Although surgical procedures to treat FAI led to satisfactory outcomes, there was a revision rate of 5.29% in the 9357 procedures in the present systematic review. The rate of progression to THA after a median follow-up of 30 months was 3.78%. Patients who have a higher BMI and/or have a pathologic acetabular index and/or undergo labral debridement during correction of FAI are more at risk for a subsequent THA. We advocate additional education of this patient population in terms of expected outcomes and suggest surgical labral repair instead of debridement if needed.

Heterotopic Ossification After Arthroscopic Procedures: A Scoping Review of the Literature

Background:

Heterotopic ossification (HO) is the formation of bone in soft tissue resultant from inflammatory processes. Lesion formation after arthroscopic procedures is an uncommon but challenging complication. Optimal prophylaxis and management strategies have not been clearly defined.

Purpose:

To present a scoping review of the pathophysiology, risk factors, diagnostic modalities, prophylaxis recommendations, and current treatment practices concerning HO after arthroscopic management of orthopaedic injuries.

Study Design:

Scoping review; Level of evidence, 4.

Methods:

A scoping review via a PubMed search was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. The search strategy was based on the terms “heterotopic ossification” AND “arthroscopy.” The clinical outcomes review included studies on the arthroscopic management of orthopaedic injuries in which the primary subject matter or a secondary outcome was the development of HO. An analysis of the pathophysiology, diagnostic modalities, and management options was reported.

Results:

A total of 43 studies (33,065 patients) reported on HO after hip arthroscopy, while 21 (83 patients) collectively reported on HO after arthroscopic procedures to the shoulder, elbow, knee, or ankle; however, management techniques were not standardized. Identified risk factors for HO included male sex and mixed impingement pathology, while intraoperative capsular management was not suggested as a contributing factor. Diagnosis of ossification foci was performed using radiography and computed tomography. The rate of HO after hip arthroscopy procedures approached 46% without prophylaxis, and administration of nonsteroidal anti-inflammatory drugs (NSAIDs) decreased occurrence rates to 4% but carries associated risks. External beam radiation has not been exclusively studied for use after arthroscopic procedures.

Conclusion:

HO is a known complication after arthroscopic management of orthopaedic injuries. NSAID prophylaxis has been demonstrated to be effective after hip arthroscopy procedures. Patients with persistent symptoms and mature lesions may be indicated for surgical excision, although variability is present in patient-reported outcome scores postoperatively.

Favorable Outcomes of Revision Hip Arthroscopy Irrespective of Whether Index Surgery was Performed by the Same Surgeon or a Different Surgeon

The purpose of this study was to compare minimum 2-year patient-reported outcomes (PROMs) after revision hip arthroscopy between two different patient cohorts who had undergone primary hip arthroscopy with the same surgeon (SS) and a different surgeon (DS). We hypothesized no difference in clinical outcomes between the groups despite differences in intraoperative findings based on the surgical decision making in a revision setting at a high-volume center.

Impact of bone deformities and labral and cartilage lesions on early functional results of arthroscopic treatment of femoroacetabular impingement

INTRODUCTION

Femoroacetabular impingement (FAI) is a frequent cause of inguinal pain. Treatment failure rates range between 2.9% and 13.2%. The aim of the present study was to assess the impact of preoperative bone deformities (BD), labral lesions (LL) and cartilage lesions (CL) on clinical results of arthroscopic treatment of FAI.

MATERIAL AND METHOD

A prospective operational study included patients undergoing hip arthroscopy for FAI. All patients had full radiographic work-up and clinical assessment on Non-Arthritic Hip Score (NAHS), preoperatively and at 1year. Hips with Tönnis grade>1, coxa profunda [VCE (vertical center edge angle)>35°] or borderline dysplasia (VCE<25°) were excluded. The Czerny classification was used for the labrum and the Beck classification for the cartilage. The aim of the study was to assess the impact of preoperative BD, LL and CL on clinical results of arthroscopic treatment of FAI. The study hypothesis was that type of lesion does not influence early functional results at 1year, whatever the technique used for the labrum.

RESULTS

One hundred and ninety-seven patients were included. Mean preoperative NAHS was 59.1±17.5. There were 145 patients with labral suture (73.6%), 42 with labral debridement (21.3%) and 10 with conservative treatment (5.1%). At 1year, mean NAHS was 88.1±15.3: i.e., a significant improvement (p<2.2×10^-16). Improvement was also significant in the debridement, non-operative and suture subgroups. BD showed significant correction in the overall population (alpha angle 48.2° postoperatively versus 66.7° preoperatively; crossing sign in 14.5% versus 62.9% of cases). There were no significant differences in functional scores according to extension or type of labral or cartilage lesion. At follow-up, 3 patients (1.5%) required repeat arthroscopy.

CONCLUSION

The present study showed that early functional results of arthroscopic treatment of FAI were unaffected by the severity of bone deformity (alpha and VCE angles), or extension or type of labral or cartilage lesion. Regardless of BD, LL and CL, 1-year clinical progression was satisfactory when all bone deformities were treated by the arthroscopic procedure.

LEVEL OF EVIDENCE

IV; prospective non-comparative study.

Intraoperative Computer Vision Integrated Interactive Fluoroscopy Correlates With Successful Femoroplasty on Clinic-Based Radiographs

PURPOSE

To quantitatively evaluate computer vision interface (CVI)-guided femoroplasty in the arthroscopic treatment of femoroacetabular impingement syndrome and compare those results with traditional unguided resections.

METHODS

Consecutive patients undergoing hip arthroscopy for femoroacetabular impingement syndrome between July 2019 and October 2019 were evaluated. Cases with CVI were identified along with controls, consisting of patients from the same study period who underwent surgery without the CVI and were balanced for age, sex, laterality, and preoperative alpha angles. Alpha angles were measured on pre- and postoperative clinic radiographs, as well as intraoperatively for the CVI group. Cam resections were quantified by measuring pre- and postresection alpha angles and compared between groups. The correlation between CVI views and office-based radiographs was assessed, and the 3 CVI views that best correlated with each of the 3 standard clinic radiographs were evaluated for accuracy and performance in detection of cam deformity with alpha angle ≥48° with the clinic-based films as the reference.

RESULTS

A total of 49 patients (51 hips) (average age, 28.7; 33 female patients) in the CVI group, and 51 patients (51 hips) (average age: 29.9; 35 female patients) in the control group. There were no significant differences between groups with respect to age, sex, laterality, or preoperative alpha angle (all P > .05). Significant alpha angle reduction occurred on all intraoperative and postoperative clinic views (all P < .01). The CVI views that best correlated with the clinic radiographs were 11:45 with the anteroposterior (ρ = 0.588, P = .0025), 12:30 with the Dunn lateral (ρ = 0.632, P = .0009), and 1:45 with the false-profile (ρ = 0.575, P = .0033). Greater reliability was observed with 12:30/Dunn (accuracy = 83.33%, P < .0001; sensitivity = 77.14%; specificity = 87.76%) and 1:45/false-profile (accuracy = 82.35%, P = .0051; sensitivity = 81.82%; specificity = 82.61%) than with 11:45/anteroposterior (accuracy = 69.15%, P = .0077; sensitivity = 56.10%; specificity = 79.25%).

CONCLUSIONS

CVI-guided cam resection results in successful resection of proximal femur cam lesions and represents a femoroplasty templating method that does not require preoperative computed tomography imaging or additional invasive intraoperative referencing modules. The accuracy and adequacy of this resection was validated by comparison with routine clinic radiographs.

LEVEL OF EVIDENCE

Therapeutic Level III: retrospective comparative analysis.

Hip Arthroscopy for Femoroacetabular Impingement Syndrome Results in 2 Recovery Patterns Based on Preoperative Pain and on Arthritis: Improvers and Non-improvers

Purpose

To analyze whether subgroups of patients could be distinguished with different functional recovery trajectories after hip arthroscopy for femoroacetabular impingement (FAI) syndrome and to identify differences between those subgroups using data from our prospective cohort registration.

Methods

We retrospectively reviewed the prospectively registered data of patients who had undergone hip arthroscopy for FAI syndrome in our clinic from 2015 through 2018. Latent class growth modeling and growth mixture modeling were used to identify and classify groups of patients according to the trajectory of functional recovery using the Hip Outcome Score–Activities of Daily Life (HOS-ADL). We used univariable analysis and descriptive statistics to explore whether differences in group membership could be identified.

Results

A total of 100 patients were analyzed. Growth mixture modeling identified 2 main types of recovery pattern after surgery: patients in whom the HOS-ADL improved significantly after surgery to 90, whom we called the “improvers” (with fast initial improvement within 3 months that is maintained during follow-up), and patients who did not significantly benefit from surgery (with only mild improvement in the HOS-ADL at 3 months and no further change during follow-up), whom we called the “non-improvers.” Univariable analysis and comparison of differences between subgroups showed higher preoperative visual analog scale scores for pain and more intraoperative arthrosis of the femoral head for the non-improvers.

Conclusions

We identified 2 main types of recovery pattern after arthroscopic treatment of FAI syndrome: improvers and non-improvers. Both groups recover in a different manner postoperatively. Preoperative pain and intraoperative arthrosis of the femoral head differed in the non-improvers compared with the improvers.

Level of evidence

Level III, retrospective cohort study.

Good Outcome Scores and Low Conversion Rate to THA 10 Years After Hip Arthroscopy for the Treatment of Femoroacetabular Impingement

BACKGROUND

Arthroscopic treatment of symptomatic femoroacetabular impingement (FAI) has promising short-term to mid-term results. In addition to treating acute pain or impaired function, the goal of hip-preserving surgery is to achieve a lasting improvement of hip function and to prevent the development of osteoarthritis. Long-term results are necessary to evaluate the effectiveness of surgical treatment and to further improve results by identifying factors associated with conversion to THA.

QUESTIONS/PURPOSES

(1) How do the Merle d'Aubigné-Postel scores change from before surgery to follow-up of at least 10 years in patients undergoing hip arthroscopy for the treatment of FAI? (2) What is the cumulative 10-year survival rate of hips with the endpoints of conversion to THA or a Merle d'Aubigné-Postel score less than 15? (3) Which factors are associated with conversion to THA?

METHODS

Between 2003 and 2008, we treated 63 patients (65 hips) for symptomatic FAI with hip arthroscopy at our institution. During that period, the indications for using arthroscopy were correction of anterior cam morphology and anterolateral rim trimming with debridement or reattachment of the labrum. We excluded patients who were younger than 16 years and those who had previous trauma or surgery of the hip. Based on that, 60 patients (62 hips) were eligible. A further 17% (10 of 60) of patients were excluded because the treatment was purely symptomatic without treatment of cam- and/or pincer-type morphology. Of the 50 patients (52 hips) included in the study, 2% (1) of patients were lost before the minimum study follow-up of 10 years, leaving 49 patients (51 hips) for analysis. The median (range) follow-up was 11 years (10 to 17). The median age at surgery was 33 years (16 to 63). Ninety percent (45 of 50) of patients were women. Of the 52 hips, 75% (39 of 52) underwent cam resection (femoral offset correction), 8% (4 of 52) underwent acetabular rim trimming, and 17% (9 of 52) had both procedures. Additionally, in 35% (18 of 52) of hips the labrum was debrided, in 31% (16 of 52) it was resected, and in 10% (5 of 52) of hips the labrum was reattached. The primary clinical outcome measurements were conversion to THA and the Merle d'Aubigné-Postel score. Kaplan-Meier survivorship and Cox regression analyses were performed with endpoints being conversion to THA or Merle d'Aubigné-Postel score less than 15 points.

RESULTS

The clinical result at 10 years of follow-up was good. The median improvement of the Merle d'Aubigné-Postel score was 3 points (interquartile range 2 to 4), to a median score at last follow-up of 17 points (range 10 to 18). The cumulative 10-year survival rate was 92% (95% CI 85% to 99%) with the endpoints of conversion to THA or Merle d'Aubigné-Postel score less than 15. Factors associated with conversion to THA were each year of advancing age at the time of surgery (hazard ratio 1.1 [95% CI 1.0 to 1.3]; p = 0.01) and preoperative Tönnis Grade 1 compared with Tönnis Grade 0 (no sign of arthritis; HR 17 [95% CI 1.8 to 166]; p = 0.01).

CONCLUSION

In this series, more than 90% of patients retained their native hips and reported good patient-reported outcome scores at least 10 years after arthroscopic treatment of symptomatic FAI. Younger patients fared better in this series, as did hips without signs of osteoarthritis. Future studies with prospective comparisons of treatment groups are needed to determine how best to treat complex impingement morphologies.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Prognostic Factors for Conversion to Arthroplasty after Hip Arthroscopy. Review of the Literature

Arthroscopic techniques in the treatment of femoroacetabular impingement have experienced an exponential increase over recent years for both diagnosis and treatment. The main risks with treatment are poor clinical outcomes and the conversion to prosthesis. Better knowledge and understanding of the various risk factors leading to prosthesis will improve patient selection for arthroscopic treatments rendering better results. The published papers that have been selected are related to series of hip arthroscopies with risk factors that lead to total hip arthroplasty (THA), in the PubMed database, without a time limit, number of patients, or follow-up time. We selected over 302 papers, 19 papers that show risk factors for conversion to THA. The main risk factors found were femoral chondropathy grade III/IV (relative risk 58.1-12 times increased), acetabular (20-2.96 times), an articular space <2 mm (39-4.26 times), age (14.6-1.06 times), Tönnis 2 in radiographic studies (7.73-3.1 times), obesity (5.6-2.3 times), and osteoarthritis (4.6-2.4 times). There are several risk factors which in an isolated way, highly increase the risk of THA. Some of them have a clear relationship (chondropathy, reduced joint space, Tönnis 2, and osteoarthritis). Based on the review we observed that the elements that are most associated with a conversion to THA after a hip arthroscopy are a high degree of femoral and acetabular chondropathy, a reduced joint space below 2 mm, older age, Tönnis 2, obesity, and hip osteoarthritis.

There is no definite consensus on the adequate radiographic correction in arthroscopic osteochondroplasty for femoroacetabular impingement: a systematic review and meta-analysis

PURPOSE

The purpose of this study is to evaluate and define what is considered an adequate radiographic correction in arthroscopic osteochondroplasty for FAI and to secondarily assess how radiographic outcomes relate to patient reported outcomes and complications.

METHODS

The databases EMBASE, PubMed, and MEDLINE were searched for relevant literature from database inception until January 2021. Studies were screened by two reviewers independently and in duplicate for studies reporting on post-operative radiographic outcomes in arthroscopic osteochondroplasty for FAI. Data on radiographic outcomes as well as data reporting functional outcomes and complications were recorded. A meta-analysis was used to combine the mean pre- and post-operative radiographic outcomes using a random effects model. A risk of bias assessment was performed for all included studies using the MINORS score.

RESULTS

The most commonly reported radiographic outcome was the alpha angle with a pooled mean post-operative angle of 44° (95% CI 41°-46°), and mean pre- to post-surgical difference of - 19° (- 22 to - 16, I² = 96%), followed by the LCEA with a pooled mean post-operative angle of 30° (95% CI 29-31) and mean difference after surgery of - 4° (- 6 to - 1, I² = 97%,). Eleven studies reported on the correlation between radiographic and clinical outcomes with no consistent consensus correlation found amongst the included studies. Similarly, six studies correlated radiographic outcomes with conversion to THA with no consistent consensus correlation found amongst the included studies.

CONCLUSION

Based on this review, the main conclusion is that there is no consensus definition on the optimal radiographic correction for FAI and there was no consistent correlation between radiographic correction and functional outcomes. However, based on the uniform improvement in functional outcomes, this review suggests a post-operative alpha angle target of 44° with a correction target of 19° and LCEA target of 30° with a correction target of 3°.

LEVEL OF EVIDENCE

IV.

The lateral joint space width is essential for the outcome after arthroscopically assisted mini-open arthrotomy for treatment of a femoroacetabular impingement: an analysis of prognostic factors for the success of this hip-preserving technique

PURPOSE

The purpose of this study was to analyze predicting factors for a conversion to a total hip replacement (THR) after mini-open arthrotomy for treatment of femoroacetabular impingement (FAI).

METHODS

Between 2011 and 2016, we identified 32 patients, who were treated for FAI with a mini-open arthrotomy and received after mean time of 2.1 ± 1.4 years a THR. These patients were compared to 47 cases who did not receive a THR (mean follow-up: 4.3 ± 0.7 years) to explore pre- and intra-operative factors associated with a conversion to THR. The results were presented in separated Kaplan-Meier curves with log rank test for significance and hazard ratios.

RESULTS

A lateral joint space width of > 4 mm showed a higher THR-free survival rate compared to < 4 mm (p = 0.001); analogously one-sided (acetabular/femoral) 3-4° cartilage damage had a comparable THR-free survival rate than 1-2° kissing lesions (p = 0.001). Furthermore, an intact labrum without treatment and good cartilage status, a refixed labrum after rim resection in case of a pincer type FAI, or a refixed teared labrum were associated with a longer THR-free time than an untreated labrum accompanied by a poor cartilage status or an ossified labrum (p = 0.002). The strongest independent factor for a conversion to THR was femoral cartilage damage grade 1 and higher (p = 0.046). However, the rate of available patients was 53.0%.

CONCLUSION

The success of a joint-preserving mini-open arthrotomy seems to be dependent on the status of the radiological joint space width and the intra-operative cartilage status of the lateral edge.

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.

Revision Hip Arthroscopy in the Native Hip: A Review of Contemporary Evaluation and Treatment Options

Hip arthroscopy is a reproducible and efficacious procedure for the treatment of femoroacetabular impingement syndrome (FAIS). Despite this efficacy, clinical failures are observed, clinical entities are challenging to treat, and revision hip arthroscopy may be required. The most common cause of symptom recurrence after a hip arthroscopy that leads to a revision arthroscopy is residual cam morphology as a result of inadequate femoral osteochondroplasty and restoration of head–neck offset, though several other revision etiologies including progressive chondral and labral pathologies also exist. In these cases, it is imperative to perform a comprehensive examination to identify the cause of a failed primary arthroscopy as to assess whether or not a revision hip arthroscopy procedure is indicated. When a secondary procedure is indicated, approaches may consist of revision labral repair, complete labral reconstruction, or labral augmentation depending on labral integrity. Gross instability or imaging-based evidence of microinstability may necessitate capsular augmentation or plication. If residual cam or pincer morphology is present, additional resection of the osseous abnormalities may be warranted. This review article discusses indications, the evaluation of patients with residual symptoms after primary hip arthroscopy, and the evaluation of outcomes following revision hip arthroscopy through an evidence-based discussion. We also present a case example of a revision hip arthroscopy procedure to highlight necessary intraoperative techniques during a revision hip arthroscopy.

Medium-term results of arthroscopic treatment for femoroacetabular impingement

INTRODUCTION

Femoroacetabular impingement (FAI) is a dynamic pathomechanical process of the femoral head-neck junction. Arthroscopic surgery for FAI has increased exponentially in the last decade, and this trend is expected to increase.

SOURCE OF DATA

Recent published literatures.

AREAS OF AGREEMENT

FAI promotes quick rehabilitation and low complication rates in the short-term follow-up.

AREAS OF CONTROVERSY

Despite the growing interest on arthroscopic surgery for FAI, current evidence regarding the medium- and long-term role of arthroscopy are unsatisfactory.

GROWING POINTS

Systematically summarize current evidences, analyse the quantitative available data and investigate the medium- and long-term outcomes of arthroscopic surgery for FAI.

AREAS TIMELY FOR DEVELOPING RESEARCH

Arthroscopic surgery achieves very satisfactory outcomes for patients with FAI at a mean follow-up of 4 years.

Posterior Extra-articular Ischiofemoral Impingement Can Be Caused by the Lesser and Greater Trochanter in Patients With Increased Femoral Version: Dynamic 3D CT-Based Hip Impingement Simulation of a Modified FABER Test

Background:

Posterior extra-articular hip impingement has been described for valgus hips with increased femoral version (FV). These patients can present clinically with lack of external rotation (ER) and extension and with a positive posterior impingement test. But we do not know the effect of the combination of deformities, and the impingement location in early flexion is unknown.

Purpose:

To evaluate patient-specific 3-dimensional computed tomography (3D CT) scans of hips with increased FV and control hips for differences in range of motion, location and prevalence of osseous posterior intra- and extra-articular hip impingement.

Study Design:

Case series; Level of evidence, 4.

Methods:

Osseous 3D models based on segmentation of 3D CT scans were analyzed for 52 hips (38 symptomatic patients) with positive posterior impingement test and increased FV (>35°). There were 26 hips with an increased McKibbin instability index >70 (unstable hips). Patients were mainly female (96%), with an age range of 18 to 45 years. Of them, 21 hips had isolated increased FV (>35°); 22 hips had increased FV and increased acetabular version (AV; >25°); and 9 valgus hips (caput-collum-diaphyseal angle >139°) had increased FV and increased AV. The control group consisted of 20 hips with normal FV, normal AV, and no valgus (caput-collum-diaphyseal angle <139°). Validated 3D CT–based collision detection software for impingement simulation was used to calculate impingement-free range of motion and location of hip impingement. Surgical treatment was performed after the 3D CT–based impingement simulation in 27 hips (52%).

Results:

Hips with increased FV had significantly (P < .001) decreased extension and ER at 90° of flexion as compared with the control group. Posterior impingement was extra-articular (92%) in hips with increased FV. Valgus hips with increased FV and AV had combined intra- and extra-articular impingement. Posterior hip impingement occurred between the ischium and the lesser trochanter at 20° of extension and 20° of ER. Impingement was located between the ischium and the greater trochanter or intertrochanteric area at 20° of flexion and 40° of ER, with a modification of the flexion-abduction-ER (FABER) test.

Conclusion:

Posterior extra-articular ischiofemoral hip impingement can be caused by the lesser and greater trochanter or the intertrochanteric region. We recommend performing the modified FABER test during clinical examination in addition to the posterior impingement test for female patients with high FV. In addition, 3D CT can help for surgical planning, such as femoral derotation osteotomy and/or hip arthroscopy or resection of the lesser trochanter.

High Risk of Conversion to THA After Femoroacetabular Osteoplasty for Femoroacetabular Impingement in Patients Older than 40 Years

BACKGROUND

Femoroacetabular impingement (FAI) is a recognized cause of hip pain and decreased quality of life and has been linked to primary idiopathic hip osteoarthritis (OA). Although the operative indications for FAI have expanded to include older patients, we do not know whether there is an increased risk of conversion to THA after femoroacetabular osteoplasty (FAO) via the mini-open approach for FAI in patients older than 40 years compared with younger patients, after controlling for other confounding variables.

QUESTIONS/PURPOSES

(1) After matching for gender, BMI, preoperative symptomatic period, surgeon experience, Tönnis grade, and degree of chondral lesion, are patients older than 40 years who undergo FAO for FAI more likely to be revised to THA at a minimum of 2 years' follow-up than are patients younger than 40? (2) Is there a difference in delta (postoperative minus preoperative) improvement in functional outcome scores in those patients who did not go on to THA between patients older than and younger than 40 years?

METHODS

Between 2003 and 2017, one surgeon performed 281 FAOs via the mini-open approach in patients older than 40 years and 544 of the same procedure in patients younger than 40 years. During that period, the general indications for FAO were the same in both age groups: (1) history and physical exam consistent with FAI, (2) radiographic evidence of focal impingement (cam, pincer, or both), (3) evidence of labral or chondrolabral tears, and (4) minimal to no arthritic changes (all four criteria required). In general, age was not used as a contraindication for surgery. A total of 86% (241 of 281) of patients older than 40 and 91% (494 of 544) of those younger than 40 were available for minimum of 2 years' follow-up, had complete datasets (radiographs as well as preoperative and most recent patient-reported outcomes scores) at a minimum of 2 years after surgery, and were considered eligible for the match. Propensity score matching was used to match for BMI, gender, preoperative symptomatic period, surgeon experience, Tönnis grade, and degree of intraoperative chondral lesion. We matched at a 1:2 ratio 130 patients older than age 40 with 260 patients younger than age 40. The mean ± SD follow-up duration for both groups was 5 ± 2 years. The mean age of the cohort of interest was 47 ± 5 years compared with 28 ± 7 years in the control. Fifty-four percent (70 of 130) of patients older than 40 years were women and 46% (60 of 130) were men; for those younger than 40, 51% (133 of 260) of participants were women and 49% (127 of 260) were men. Tönnis grade distribution for patients older than 40 was as follows: 46% (60 of 130) had Grade 0, 42% (55 of 130) had Grade 1, and 12% (15 of 130) had Grade 2. In comparison, Tönnis grade for patients younger than 40 was as follows: 52% (136 of 260) had Grade 0, 38% (100 of 260) had Grade 1, and 9% (24 of 260) had Grade 2 (p = 0.49). Chondral lesion degree was determined intraoperatively as none, a partial-thickness tear, or a full-thickness tear. Tönnis grade was determined based on preoperative plain AP hip radiographs. We then compared the percentage of patients who converted to THA during the surveillance period (our primary study outcome). We also compared the difference in delta (preoperative minus postoperative) improvement in functional outcome scores using the modified Harris Hip Score (mHHS) between the groups, excluding those who had already been converted to THA.

RESULTS

In patients older than 40 years, 16% (21 of 130) converted to THA at a mean time to conversion of 2 ± 1 years compared with 7% (17 of 260) at a mean time of 2 ± 2 years in patients younger than 40 years (p = 0.01). At a mean of 5 ± 2 years after FAO, among those patients who had not undergone conversion to THA, the mean delta mHHS score for patients older than 40 was 11 ± 17, compared with 20 ± 26 for patients younger than 40 (p = 0.04).

CONCLUSION

Since approximately 1 in 6 patients older than 40 years in this series who underwent FAO for FAI opted for early conversion to THA at a mean time of 2 years after the osteoplasty procedure, and the remaining patients who did not undergo THA reported lower improvement in functional outcomes, we recommend surgeons avoid this procedure in patients in this age group until or unless we can better refine our indications. This is especially true because loss to follow-up causes us to believe that, if anything, our estimates of the risk of conversion to THA are conservative.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Preoperative risk factors in hip arthroscopy

PURPOSE

Arthroscopic surgery is a usual technique to repair hip femoroacetabular impingement. Correlation exists among surgical indication, postoperative evolution, the final result, and the necessity of prosthesis in the near future. The assessment of specific parameters allowing us to evaluate the prognosis becomes vital to improve the results. The objective of this study is to check the variables found in patients with femoroacetabular impingement (FAI) treated with hip arthroscopy, and determine which of these variables would serve as key indicators in predicting the need for subsequent arthroplasty.

METHODS

Data from FAI surgical indications (age, weight, height, BMI, gender, side, radiographic Tönnis degree, cartilage lesion degree by Acetabular Labrum Articular Disruption (ALAD) degree, VAS value, HOS, mHHS and WOMAC) were collected from cases which should have had a minimum monitoring period of 2 years from 2007 to 2017. The results of the group which needed prosthesis were compared to the results of the ones who did not.

RESULTS

Among 452 patients who were monitored for an average of 5.8 years, 82 (18.1%) required conversion to prosthesis. The variables that indicated relatively high risk were fourth-degree acetabular labrum articular disruption (ALAD) chondral injury, preoperative radiographic Grade 2 Tönnis classification, age of over 55 years, WOMAC over 45 points, and HOS-ADL under 50 points. There were no significant differences between side, gender, VAS level, nor HOS.

CONCLUSIONS

The presence of chondral injuries such as acetabular labrum articular disruption (ALAD) 4, radiographic Grade 2 Tönnis classification, higher age, higher BMI, and worse WOMAC, along with mHHS and HOS-ADL preoperative results, are factors which lead to a poor prognosis following FAI hip arthroscopic surgery, increasing the risk of prosthetic conversion in the short or medium term.

LEVEL OF EVIDENCE

Level IV.

Increased range of motion but otherwise similar clinical outcome of arthroscopy over open osteoplasty for femoroacetabular impingement at midterm follow-up: A systematic review

BACKGROUND

A systematic review was conducted comparing patient reported outcomes measures (PROMs), functional scores, and the rate of complications between arthroscopic and open treatment for femoroacetabular impingement (FAI) at mid-term follow-up.

MATERIAL AND METHODS

This systematic review was performed according to the PRISMA guidelines. The literature search was performed in October 2020. All clinical trials treating FAI using open osteoplasty or arthroscopic surgery were considered for inclusion. Only articles reporting >12 months follow-up were included.

RESULTS

Data from 97 articles (9981 procedures) were collected. At a mean 19.2 months follow-up there was no difference between the two cohorts. At a mean follow-up of 38 months, the external rotation was increased in the arthroscopic group (P < 0.0001). The modified Harris Hip Score scored greater in favour of the open osteoplasty group (P = 0.04), as did the Hip Outcome Score - Activities of Daily Living subscale (P = 0.01). At a mean 45.1 months the arthroscopic group presented greater external rotation (P < 0.0001) and SF-12 Mental (P = 0.04). The modified Harris Hip Score was greater in favour of the open osteoplasty group (P = 0.03), as was the HOS-ADL (P = 0.01). Regarding complications, the arthroscopic group experienced lower rates of subsequent revisions (P < 0.0001).

CONCLUSION

Based on the significant reduction of revisions-rate and significant increase in range of motion, arthroscopy treatment for the management of FAI may be recommended.

Mid- to Long-Term Outcomes of Hip Arthroscopy: A Systematic Review

PURPOSE

To assess mid- to long-term patient-reported outcomes (PROs) of hip arthroscopy as well as the rates of secondary surgery and to identify indications for surgery and noted predictors of failure.

METHODS

A systematic review of the current literature was performed with the terms "hip arthroscopy," "outcomes," "patient-reported outcomes," "mid-term," "5-year," "long-term," and "10-year" in the PubMed, Cochrane, and Embase databases in April of 2020 according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Data for study characteristics, patient demographics, follow-up time, indications for surgery, PROs, predictors of failure or unfavorable PROs, and rates of secondary hip preservation surgery and conversion to total hip arthroplasty were collected.

RESULTS

Thirteen articles were included. Four studies were level III and 9 were level IV. In total, 1571 hips were included, and the average follow-up time ranged from 60 to 240 months. The most common indications for hip arthroscopy were labral tears and femoroacetabular impingement syndrome. Twelve studies reported on PROs and all reported improvement at latest follow-up. The most reported on scores were the modified Harris Hip Score, Harris Hip Score, and the Hip Outcome Score-Sport Specific Subscale. When grouped based on average follow-up time, the conversion rates at the 5- and 10-year time points ranged from 3.0% to 17.9% and 2.4% to 32.5%, respectively. One study with 20-year follow-up reported a conversion rate of 41.0%. Osteoarthritis and increased age were the most cited predictors for secondary surgery or decreased PROs.

CONCLUSIONS

At mid- to long-term follow-up, patients who underwent primary hip arthroscopy demonstrated improvement in several PROs. There was great variability in rates for revision surgery and conversion to total hip arthroplasty. The most common indications for hip arthroscopy were labral tears and femoroacetabular impingement syndrome. Osteoarthritis and increased age were the most cited predictors for unfavorable outcomes.

LEVEL OF EVIDENCE

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

Midterm Follow-Up and Assessment of Cartilage Thickness by Arthro-Magnetic Resonance Imaging After Arthroscopic Cam Resection, Labral Repair, and Rim Trimming Without Labral Detachment

PURPOSE

To evaluate the clinical and radiological outcome, sum of acetabular and femoral cartilage thickness, and rate of failure in the midterm after arthroscopic treatment of femoroacetabular impingement (FAI) syndrome with femoral osteoplasty, labral repair, and rim trimming without labral detachment.

METHODS

This retrospective case series included patients with FAI syndrome who had undergone hip arthroscopy from January 2009 to December 2010 by a single surgeon, with a minimum follow-up of 55 months. Data from patients who had undergone arthroscopic hip procedures with labral repair, rim trimming, and femoral osteoplasty were analyzed pre- and postoperatively. Clinical outcome (nonarthritic hip score [NAHS], Short Form 36 [SF-36]), range of motion, progression of osteoarthritis (Tönnis grade), radiological parameters (α angle, lateral center-edge angle [LCEA], Tönnis angle), femoral and acetabular cartilage thickness (using magnetic resonance imaging [MRI]), and intraoperative findings were evaluated.

RESULTS

Of 148 hip arthroscopies performed, 97 included rim trimming, labral refixation, and femoral osteoplasty. Ten cases were lost to follow-up, leaving 87 hips. Arthroscopic revision was performed on 4 hips and total hip replacement on 4 hips, and 1 hip underwent both arthroscopic revision and total hip replacement. Excluding these 9 cases of revision, for which follow-up was not possible (retrospective study), the remaining 78 hips were followed up for a minimum of 55 months (77 ± 11.4, mean ± SD; range 55 to 124). Mean NAHS (65 to 88, P < .001), SF-36 physical subscale (65 to 85, P < .001), and the numerical pain rating scale (NRS) (5 to 1, P < .001) improved significantly. Outcome scores of minimal clinical importance (NAHS) were achieved in 67.6% of the patients. Mean range of movement improved significantly in flexion (109 to 122, P < .001) and internal rotation (10 to 22.7, P < .001). NAHS was positively associated with flexion of the hip postoperatively (r = 0.307, P = .011). In 16 cases, microfracture was performed (15 acetabular and 1 femoral). Preoperative α angles (anteroposterior and modified Dunn) were significantly higher in this cohort (P < .001, 95% confidence interval 8.9 to 25.2, P = .001). Twenty hips (28 %) progressed to worse Tönnis grades. Initial Tönnis grades were grade 0, 38; grade 1, 48; grade 2, 8. Pre- or postoperative Tönnis grades did not show any correlation with pre- or postoperative NAHS and NRS. MRI measurements at the latest follow-up (69 patients) of the femoral and acetabular cartilage thickness did not reveal any significant reduction at the 12 o'clock position.

CONCLUSION

Arthroscopic cam resection, rim trimming, and labral repair without detachment of the labrum provides good or excellent outcome in 77.1% of hips based on NAHS in the midterm. Higher range of motion in flexion is associated with higher NAHS postoperatively. Arthroscopic cam resection, rim trimming and labral repair without detachment of the labrum is a successful method for the treatment of FAI syndrome in the midterm.

LEVEL OF EVIDENCE

IV, retrospective case series.

Functional outcomes and 8-year survival after hip arthroscopy in patients with degenerative hip disease

BACKGROUND AND PURPOSE

The purpose of this study is to identify which variables may have a significant impact in mid-term survivorship following hip arthroscopy.

METHODS

This a single-centre single-surgeon retrospective study including 102 patients who underwent a hip arthroscopy procedure between August 2007 and October 2011. Each subject completed three questionnaires at final follow- up: Hip Outcome Score-Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sport (HOS-S) and Modified Harris Hip Score (m-HHS).

RESULTS

Thirty-nine patients (40 hips) were finally included in our study. Mean age was 43.1 ± 9.9 years with a three-year minimum follow-up (75.43 ± 25.2 months). Younger patients and those with a shorter duration of symptoms obtained significantly higher HOS-S and m-HSS scores. Patients who had undergone previous lumbar spinal surgery obtained significantly worse HOS-ADL scores. Patient acceptable symptom state (PASS) was achieved in 23 patients (57.5%) for m-HHS, 22 patients (55%) for HOS-ADL and 25 patients for HOS-S scores. No major complication was observed. Only four patients had minor complications. Mean survival time was 97.1 months (95% CI, 85.1 to 109.1 months), with a survival at 8 years of 69% (95% CI, 53% to 85%).

CONCLUSIONS

Our findings suggest that hip arthroscopy is a safe procedure with acceptable functional outcomes after a long follow-up. Care should be taken when treating patients with prior lumbar surgery.

LEVEL OF EVIDENCE

Level IV.

CASE SERIES

Patient-related risk factors associated with less favourable outcomes following hip arthroscopy

AIMS

This paper aims to review the evidence for patient-related factors associated with less favourable outcomes following hip arthroscopy.

METHODS

Literature reporting on preoperative patient-related risk factors and outcomes following hip arthroscopy were systematically identified from a computer-assisted literature search of Pubmed (Medline), Embase, and Cochrane Library using Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines and a scoping review.

RESULTS

Assessment of these texts yielded 101 final articles involving 90,315 hips for qualitative analysis. The most frequently reported risk factor related to a less favourable outcome after hip arthroscopy was older age and preoperative osteoarthritis of the hip. This was followed by female sex and patients who have low preoperative clinical scores, severe hip dysplasia, altered hip morphology (excess acetabular retroversion or excess femoral anteversion or retroversion), or a large cam deformity. Patients receiving workers' compensation or with rheumatoid arthritis were also more likely to have a less favourable outcome after hip arthroscopy. There is evidence that obesity, smoking, drinking alcohol, and a history of mental illness may be associated with marginally less favourable outcomes after hip arthroscopy. Athletes (except for ice hockey players) enjoy a more rapid recovery after hip arthroscopy than non-athletes. Finally, patients who have a favourable response to local anaesthetic are more likely to have a favourable outcome after hip arthroscopy.

CONCLUSION

Certain patient-related risk factors are associated with less favourable outcomes following hip arthroscopy. Understanding these risk factors will allow the appropriate surgical indications for hip arthroscopy to be further refined and help patients to comprehend their individual risk profile. Cite this article: Bone Joint J 2020;102-B(7):822-831.

Does hip preservation surgery prevent arthroplasty? Quantifying the rate of conversion to arthroplasty following hip preservation surgery

Hip arthroscopic surgery for femoroacetabular impingement and periacetabular osteotomy (PAO) for dysplasia is the most commonly used contemporary treatment for these conditions and has been shown to provide pain relief and restore function. What is less understood and perhaps of more interest to health economists, is the role of these procedures in preserving the hip joint and avoiding hip arthroplasty. The aim of this systematic review was to determine whether hip joint preservation surgery, indeed, preserves the hip joint by looking at conversion rates to total hip arthroplasty (THA). Two separate searches were undertaken, using PRISMA guidelines and utilizing PubMed and Open Athens search engines, identifying manuscripts that looked at conversion to THA following either hip arthroscopy (HA) or PAO. When considering HA, we found 64 eligible papers. Out of these studies, there were 59 430 hips with 5627 undergoing conversion to THA (9.47% [95% CI 9.23–9.71%]) with a mean conversion time of 24.42 months. Regarding PAO, there were 46 eligible papers including 4862 patients who underwent PAO with subsequent conversion to THA in 404 patients (8.31% [95% CI 7.54–9.12%]). with a mean conversion time of 70.11 months. Certain features were associated with increased conversion rates, including increasing age, worsening arthritis and joint space <2 mm. This study demonstrates that the mean conversion rates to be <10% for HA and PAO, during the mean follow-up periods of included manuscripts. Joint preserving surgery appears to defer or at least delay the need for THA.

Identifying the Most Successful Procedures in Hip Arthroscopy

Hip arthroscopy for femoral and acetabular pathologies has increased dramatically. However, there is little literature analyzing procedures as predictors of revision arthroscopy or arthroplasty. From February 2008 to November 2015, patients undergoing hip arthroscopy for a labral tear with minimum 2-year follow-up and between 18 and 60 years old were retrospectively reviewed. Those with previous surgeries, Tönnis grade greater than 1, and previous hip conditions were excluded. Follow-up was obtained for 1118 patients (1249 hips; 81.7%) with a mean age of 38.7 years (range, 18.0-60.0 years), mean body mass index of 26.4 kg/m² (range, 16.3-48.9 kg/m²), and mean follow-up of 50.2 months (range, 24.0-111.9 months). A total of 122 (9.8%) patients converted to total hip arthroplasty (mean, 35.3 months; range, 1.4-95.2 months). Multivariate analysis for predictors of total hip arthroplasty found age at surgery (hazard ratio, 1.064/y; P<.05), body mass index (nonlinear; P<.05), labral debridement (HR, 1.558; P=.03), and notchplasty (HR, 2.128; P<.05), with trochanteric bursectomy (HR, 0.367; P<.05) identified as associated with higher survivorship. A total of 124 (9.9%) patients underwent revision hip arthroscopy at a mean of 21.7 months (range, 0.10-83.3 months). Multivariate analysis for predictors of revision surgery found workers' compensation (HR, 3.352; P<.05), capsular repair (HR, 1.950; P<.05), and femoral head microfracture (HR, 2.844; P=.04) to be significant, with age at date of surgery (HR, 0.973/y; P<.05) and femoral head chondroplasty (HR, 0.241; P=.05) associated with higher survivorship. Understanding risk factors for conversion to total hip arthroplasty or revision is paramount during discussions with patients. [Orthopedics. 2020;43(3):173-181.].

Gender-Specific Sexual Activity After Hip Arthroscopy for Femoroacetabular Impingement Syndrome: Position Matters

BACKGROUND

There is limited evidence on the safety of return to sexual activity after hip arthroscopy.

AIM

To determine the positional safety of sexual activity after hip arthroscopy relative to hip instability and/or impingement risk.

STUDY DESIGN

This study is an observational study.

METHODS

12 common sexual positions were identified based on previous research. Gender-specific hip motion was then assessed for the possibility of postarthroscopic hip instability (due to disruption of iliofemoral ligament [interportal capsulotomy] repair) and/or impingement (labral or capsular compressive stress with disrupted repair) for all 12 positions (both right and left hips; 15 unique male and 14 unique female positions). Instability risk was defined as greater than 0° hip extension, greater than 30° external rotation (ER), or greater than 30° abduction. Impingement risk was defined as greater than 90° hip flexion, greater than 10° internal rotation, and greater than 10° adduction.

OUTCOMES

A majority of both male and female sexual positions caused either instability or impingement, with only 4 positions in women and 4 positions in men deemed "safe" by avoiding excessive hip motion.

RESULTS

Return to sexual activity after hip arthroscopy may cause instability in 10/15 of male positions and 5/14 female positions. Most male positions (6/10) were at risk for instability because of excessive ER. 2 positions were unstable because of a combination of ER and extension, one was due to extension, and one abduction. In female instability positions, all 5 were unstable because of excessive abduction. Impingement may be observed in 5 of 15 male positions and 6 of 14 female positions. In male impingement positions, all were due to excessive adduction. 4 female positions risked impingement due to excessive flexion and 2 positions due to internal rotation.

CLINICAL IMPLICATIONS

This study demonstrates risks that should be considered when counseling patients preoperatively and postoperatively regarding sexual activity.

STRENGTHS & LIMITATIONS

This study closely models a hip preservation patient population by using 2 young and otherwise healthy individuals. The most significant limitation of this investigation was its basis with only 2 young healthy volunteers (one male, one female) in a single motion capture session using surface-based spherical retroreflective markers from a previous investigation.

CONCLUSION

After hip arthroscopy, patients need to be made aware of the possibility of hip instability (10 of 15 men; 5 of 14 women) and impingement (5 of 15 men; 6 of 14 women) due to excessive hip motion that may compromise their outcome. Morehouse H, Sochacki KR, Nho SJ, et al. Gender-Specific Sexual Activity After Hip Arthroscopy for Femoroacetabular Impingement Syndrome: Position Matters. J Sex Med 2020;17:658-664.

Application of Machine Learning for Predicting Clinically Meaningful Outcome After Arthroscopic Femoroacetabular Impingement Surgery

BACKGROUND

Hip arthroscopy has become an important tool for surgical treatment of intra-articular hip pathology. Predictive models for clinically meaningful outcomes in patients undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS) are unknown.

PURPOSE

To apply a machine learning model to determine preoperative variables predictive for achieving the minimal clinically important difference (MCID) at 2 years after hip arthroscopy for FAIS.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Data were analyzed for patients who underwent hip arthroscopy for FAIS by a high-volume fellowship-trained surgeon between January 2012 and July 2016. The MCID cutoffs for the Hip Outcome Score-Activities of Daily Living (HOS-ADL), HOS-Sport Specific (HOS-SS), and modified Harris Hip Score (mHHS) were 9.8, 14.4, and 9.14, respectively. Predictive models for achieving the MCID with respect to each were built with the LASSO algorithm (least absolute shrinkage and selection operator) for feature selection, followed by logistic regression on the selected features. Study data were analyzed with PatientIQ, a cloud-based research and analytics platform for health care.

RESULTS

Of 1103 patients who met inclusion criteria, 898 (81.4%) had a minimum of 2-year reported outcomes and were entered into the modeling algorithm. A total of 74.0%, 73.5%, and 79.9% met the HOS-ADL, HOS-SS, and mHHS threshold scores for achieving the MCID. Predictors of not achieving the HOS-ADL MCID included anxiety/depression, symptom duration for >2 years before surgery, higher body mass index, high preoperative HOS-ADL score, and preoperative hip injection (all P < .05). Predictors of not achieving the HOS-SS MCID included anxiety/depression, preoperative symptom duration for >2 years, high preoperative HOS-SS score, and preoperative hip injection, while running at least at the recreational level was a predictor of achieving HOS-SS MCID (all P < .05). Predictors of not achieving the mHHS MCID included history of anxiety or depression, high preoperative mHHS score, and hip injections, while being female was predictive of achieving the MCID (all P < .05).

CONCLUSION

This study identified predictive variables for achieving clinically meaningful outcome after hip arthroscopy for FAIS. Patient factors including anxiety/depression, symptom duration >2 years, preoperative intra-articular injection, and high preoperative outcome scores are most consistently predictive of inability to achieve clinically meaningful outcome. These findings have important implications for shared decision-making algorithms and management of preoperative expectations after hip arthroscopy for FAI.

Patients aged in their 70s do not have a high risk of progressive osteoarthritis following arthroscopic femoroacetabular impingement correction and labral preservation surgery

PURPOSE

The purposes of this study were to (1) evaluate the effect of age on clinical outcomes of arthroscopic femoroacetabular impingement (FAI) with labral preservation surgery and (2) identify predictors of poor postoperative clinical outcomes.

METHODS

Eighty-four patients who underwent hip arthroscopic treatment for FAI between 2009 and 2013 were retrospectively reviewed. Patients were divided into three groups based on age. The Advanced age group consisted of patients over 70 years old, the Middle age group consisted of patients in their 50s and 60s, and the Younger age group consisted of patients less than 50 years of age. Total hip arthroplasty (THA) conversion, radiographic progression of osteoarthritis and patient-reported outcomes including modified Harris Hip Score (MHHS) and Non-arthritic Hip Score (NAHS) were investigated.

RESULTS

The mean follow-up period was 32.2 (range 24-60) months. THA was required in 3 patients in their 50s and 60s, which was a significantly higher rate compared to that in patients Younger than 50 years old (17% vs 0%, p = 0.036). Progression to osteoarthritis was also significantly more frequent in patients in their 50s and 60s than in patients in their 70s (50s and 60s: 33%; 70s: 0%, p = 0.030). In all age groups, the preoperative MHHS and NAHS improved at last follow-up (p < 0.001). The 50s and 60s age group [hazard ratio (HR) 6.62], preoperative mild osteoarthritic change (Tönnis grade 1, HR: 3.29) and severe cartilage damage on the acetabulum (HR: 2.63) were risk factors for progressive osteoarthritis and THA conversion.

CONCLUSIONS

Arthroscopic FAI correction and labral preservation surgery provide favourable clinical outcomes for patients over 70 years old in the absence of significant osteoarthritis and severe acetabular chondral damage. Patients in their 50s and 60s have a higher risk of both THA conversion and progressive osteoarthritis, while patients aged over 70 years show no evidence of progressive osteoarthritis. Chronologic age in isolation is not an absolute contra-indication to hip arthroscopy.

LEVEL OF EVIDENCE

III.

Postoperative Weightbearing Protocols After Arthroscopic Surgery for Femoroacetabular Impingement Does Not Affect Patient Outcome: A Comparative Study With Minimum 2-Year Follow-up

PURPOSE

To evaluate the effects of immediate postoperative weightbearing protocols after hip arthroscopy for femoroacetabular impingement (FAI) with minimum 2-year follow-up, as measured by patient-reported outcome measures and satisfaction rates.

METHODS

Between January 2011 and June 2016, patients undergoing hip arthroscopy for FAI and labral tears were reviewed. Exclusion criteria was previous hip pathology or arthroscopy, active Workers' Compensation claims, and concomitant pathologies impeding weightbearing. Patients who were operated on before September 2013 were treated with 3 weeks of postoperative non-weightbearing (NWB), with weightbearing as tolerated (WBAT) thereafter. From October 2013, patients were allowed immediate postoperative WBAT.

RESULTS

A total of 351 hip arthroscopic surgeries were performed; 133 of these patients met the inclusion criteria. Of the 133 included patients, 69 were in the NWB group and 64 were in the WBAT group. No differences were found in terms of sex (P = .603) or age (P = .241). No differences were found in postoperative scores (the Modified Harris Hip Score was 84.5 [range 79-89] for NWB vs 86.7 [78-89] for WBAT [P = .0.523], and the Hip Outcome Score was 83.1 [78-88] vs 88.4 [80-90], respectively; P = .130). Subjective rates of improvement, satisfaction score and the will to undergo surgery again did not differ between the groups (P = .674, P = .882, P = .730). The rate of subjects who met or exceeded the MCID in the NWB and WBAT groups was 82.6% and 81.2% for the Modified Harris Hip Score (P = .838) and 79.7% and 82.8% for the Hip Outcome Score (P = .647). There were no reported complications. Limitations include the possibility of the study being underpowered.

CONCLUSIONS

After a 2-year minimum follow-up, patient-reported outcome measures and satisfactory rates with immediate weightbearing after hip arthroscopy for isolated FAI syndrome and labral tears do not differ significantly from results after strict NWB rehabilitation protocols. Revising weightbearing restrictions may allow for a more comfortable rehabilitation process after arthroscopic hip surgery for FAI and labral repair.

LEVEL OF EVIDENCE

Level 3 - case-control study.