Use of Hip Arthroscopy and Risk of Conversion to Total Hip Arthroplasty: A Population-Based Analysis

Utility of MRI for Patients 45 Years Old and Older With Hip or Knee Pain: A Systematic Review

BACKGROUND. MRI utility for patients 45 years old and older with hip or knee pain is not well established. OBJECTIVE. We performed this systematic review to assess whether MRI-diagnosed hip or knee pathology in patients 45 years old and older correlates with symptoms or benefits from arthroscopic surgery. EVIDENCE ACQUISITION. A literature search (PubMed, Web of Science, Embase) of articles published before October 3, 2022, was performed to identify original research pertaining to the study question. Publication information, study design, cohort size, osteoarthritis severity, age (range, mean), measured outcomes, minimum follow-up length, and MRI field strength were extracted. Study methods were appraised with NIH's study quality assessment tools. EVIDENCE SYNTHESIS. The search yielded 1125 potential studies, of which 31 met the inclusion criteria (18 knee, 13 hip). Knee studies (10 prospective, eight retrospective) included 5907 patients (age range, 45-90 years). Bone marrow edema-like lesions, joint effusions, and synovitis on MRI were associated with symptoms. In patients with osteoarthritis, meniscal tears were less likely to be symptom generators and were less likely to respond to arthroscopic surgery with osteoarthritis progression. Hip studies (11 retrospective, two prospective) included 6385 patients (age range, 50 to ≥ 85 years). Patients with Tönnis grade 2 osteoarthritis and lower with and without femoroacetabular impingement (FAI) showed improved outcomes after arthroscopy, suggesting a role for MRI in the diagnosis of labral tears, chondral lesions, and FAI. Although this group benefited from arthroscopic surgery, outcomes were inferior to those in younger patients. Variability in study characteristics, follow-up, and outcome measures precluded a meta-analysis. CONCLUSION. In patients 45 years old and older, several knee structural lesions on MRI correlated with symptoms, representing potential imaging biomarkers. Meniscal tear identification on MRI likely has diminished clinical value as osteoarthritis progresses. For the hip, MRI can play a role in the diagnosis of labral tears, chondral lesions, and FAI in patients without advanced osteoarthritis. CLINICAL IMPACT. Several structural lesions on knee MRI correlating with symptoms may represent imaging biomarkers used as treatment targets. Osteoarthritis, not age, may play the greatest role in determining the utility of MRI for patients 45 years old and older with hip or knee pain.

Increased rate of out-of-network surgeon selection for hip arthroscopy compared to more common orthopedic sports procedures

Background

Demand for hip arthroscopy (HA) has increased, but shortfalls in HA training may create disparities in care access. This analysis aimed to (1) compare out-of-network (OON) surgeon utilization for HA with that of more common orthopedics sports procedures, including rotator cuff repair (RCR), partial meniscectomy (PM), and anterior cruciate ligament reconstruction (ACLR), (2) compare the HA OON surgeon rate with another less commonly performed procedure, meniscus allograft transplant (MAT), and (3) analyze trends and predictors of OON surgeon utilization.

Methods

The 2013-2017 IBM MarketScan database identified patients under 65 who underwent HA, RCR, PM, ACLR, or MAT. Demographic differences were determined using standardized differences. Cochran-Armitage tests analyzed trends in OON surgeon utilization. Multivariable logistic regression identified predictors of OON surgeon utilization. Statistical significance was set to p < 0.05 and significant standardized differences were >0.1.

Results

410,487 patients were identified, of which 12,636 patients underwent HA, 87,607 RCR, 233,241 PM, 76,700 ACLR, and 303 MAT. OON surgeon utilization increased for HA, rising from 7.98 % in 2013 to 9.37 % in 2017 (p = 0.026). Compared to RCR, PM, and ACLR, HA was associated with higher likelihood of OON surgeon utilization. Usage of ambulatory surgery centers (ASCs) was predictive of higher OON surgeon rates along with procedure year, insurance plan type, and geographic region. HA performed in an ASC was 13 % less likely to have an OON surgeon (p = 0.047).

Conclusion

OON surgeon utilization generally declined but increased for HA. HA was a predictor of OON surgeon status, possibly because HA is a technically complicated procedure with fewer trained in-network providers. Other predictors of OON surgeon status included ASC usage, PPO/EPO plan type, and Northeast geographic region. There is a need to improve access to experienced HA providers-perhaps with prioritization of HA training in residency and fellowship programs-in order to address rising OON surgeon utilization.

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.

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

BACKGROUND

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

PURPOSE

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

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

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

RESULTS

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

CONCLUSION

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

Hip Arthroscopy Trends: Increasing Patient Out-of-Pocket Costs, Lower Surgeon Reimbursement, and Cost Reduction With Utilization of Ambulatory Surgery Centers

PURPOSE

To (1) report on trends in immediate procedure reimbursement, patient out-of-pocket expenditures, and surgeon reimbursement in hip arthroscopy (2) compare trends in ambulatory surgery centers (ASC) versus outpatient hospitals (OH) utilization; (3) quantify the cost differences (if any) associated with ASC versus OH settings; and 4) determine the factors that predict ASC utilization for hip arthroscopy.

METHODS

The cohort for this descriptive epidemiology study was any patient over 18 years identified in the IBM MarketScan Commercial Claims Encounter database who underwent an outpatient hip arthroscopy, identified by Current Procedural Terminology codes, in the United States from 2013 to 2017. Immediate procedure reimbursement, patient out-of-pocket expenditure, and surgeon reimbursement were calculated, and a multivariable model was used to determine the influence of specific factors on these outcome variables. Statistically significant P values were less than .05, and significant standardized differences were more than 0.1.

RESULTS

The cohort included 20,335 patients. An increasing trend in ASC utilization was observed (P = .001), and ASC utilization for hip arthroscopy was 32.4% in 2017. Patient out-of-pocket expenditures for femoroacetabular impingement surgery increased 24.3% over the study period (P = .003), which was higher than the rate for immediate procedure reimbursement (4.2%; P = .007). ASCs were associated with $3,310 (28.8%; P = .001) reduction in immediate procedure reimbursement and $47 (6.2%; P = .001) reduction in patient out-of-pocket expenditure per hip arthroscopy.

CONCLUSIONS

ASCs provide a significant cost difference for hip arthroscopy. Although there is an increasing trend toward ASC utilization, it remains relatively low at 32.4% in 2017. Thus, there are opportunities for expanded ASC utilization, which is associated with significant immediate procedure reimbursement difference of $3,310 and patient out-of-pocket expenditure difference of $47 per hip arthroscopy case, ultimately benefiting healthcare systems, surgeons, and patients alike.

LEVEL OF EVIDENCE

Level III, retrospective comparative trial.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

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

Patients aged 50-75 years take longer to achieve the patient acceptable symptom state than patients aged 20-34 years following primary hip arthroscopy for femoroacetabular impingement syndrome

PURPOSE

Though an increasing number of adults older than 50 years are undergoing hip arthroscopy for treatment of Femoroacetabular Impingement Syndrome (FAIS), it is unclear how their timeline for functional outcome improvement compares to that of younger patients. The purpose of this study was to assess the impact of age on time to achieving the Minimum Clinically Important Difference (MCID), Substantial Clinical Benefit (SCB), and Patient Acceptable Symptom State (PASS) following primary hip arthroscopy for FAIS.

METHODS

A retrospective comparative single-surgeon cohort study of primary hip arthroscopy patients with minimum 2-year follow-up was conducted. Age categories were 20-34 years, 35-49 years, and 50-75 years. All subjects completed the modified Harris Hip Score (mHHS) prior to surgery and at 6-month, 1-year, and 2-year follow-up. MCID and SCB cutoffs were defined as pre-to-postoperative increases in mHHS by ≥ 8.2 and ≥ 19.8, respectively. PASS cutoff was set at postoperative mHHS ≥ 74. Time to achievement of each milestone was compared using interval-censored survival analysis. The effect of age was adjusted for Body Mass Index (BMI), sex, and labral repair technique using an interval-censored proportional hazards model.

RESULTS

Two hundred eighty-five patients were included in the analysis with 115 (40.4%) aged 20-34 years, 92 (32.3%) aged 35-49 years, and 78 (27.4%) aged 50-75 years. There were no significant differences between groups in time to achievement for the MCID (n.s.) or SCB (n.s.). However, patients in the oldest group had significantly longer time to PASS than those in the youngest group, both in the unadjusted analysis (p = 0.02) and after adjusting for BMI, sex, and labral repair technique (HR 0.68, 95% CI 0.48-0.96, p = 0.03).

CONCLUSION

Achievement of the PASS, but not the MCID or SCB, is delayed among FAIS patients aged 50-75 years who undergo primary hip arthroscopy compared to those aged 20-34 years. Older FAIS patients should be counseled appropriately about their longer timeline to achieving hip function comparable to their younger counterparts.

LEVEL OF EVIDENCE

III.

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.

Increased Risk of Lateral Femoral Cutaneous Nerve Injury in Patients With Previous Hip Arthroscopy Who Underwent a Direct Anterior Approach Total Hip Arthroplasty

Purpose

To evaluate the rates of lateral femoral cutaneous nerve (LFCN) injury in patients who underwent a direct anterior approach (DAA) total hip arthroplasty (THA) with and without previous hip arthroscopy.

Methods

We retrospectively investigated consecutive DAA THAs performed by a single surgeon. These cases were grouped into patients with and without a history of previous ipsilateral hip arthroscopy. LFCN sensation was assessed during the initial follow-up (6 weeks) and 1-year (or most recent) follow-up visits. The incidence and character of LFCN injury was compared between the 2 groups.

Results

In total, 166 patients underwent a DAA THA with no previous hip arthroscopy, and 13 had a history of previous arthroscopy. Of the 179 total patients who underwent THA, 77 experienced some form of LFCN injury at initial follow-up (43%). The rate of injury for the cohort with no previous arthroscopy was 39% (n = 65/166) on initial follow-up, whereas the rate of injury for the cohort with a history of previous ipsilateral arthroscopy was 92% (n =12/13) on initial follow-up (P < .001). In addition, although the difference was not significant, 28% (n = 46/166) of the group without history of previous arthroscopy and 69% (n = 9/13) of the group with a history of previous arthroscopy had continued symptoms of LFCN injury at most recent follow-up.

Conclusions

In this study, patients who underwent hip arthroscopy before an ipsilateral DAA THA were at increased risk of LFCN injury compared with patients who underwent a DAA THA without a previous hip arthroscopy. At final follow-up of patients with initial LFCN injury, symptoms resolved in 29% (n = 19/65) of patients with no previous hip arthroscopy and 25% (n = 3/12) of patients with previous hip arthroscopy.

Level of Evidence

Level III, case-control study.

Is Prior Hip Arthroscopy Associated With Higher Complication Rates or Prolonged Opioid Claims After Total Hip Arthroplasty? A Matched Cohort Study

Background:

Hip arthroscopy (HA) procedures have increased exponentially in recent years. Their effect on outcomes after subsequent total hip arthroplasty (THA) remains unclear.

Purpose:

To compare rates of complications and opioid claims after elective THA among patients with prior HA versus controls.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Patients who underwent THA were identified in the PearlDiver database. Arthroplasty performed for hip fractures and hip avascular necrosis were excluded. Within this population, patients with HA before arthroplasty (n = 3156) were propensity score matched 1:1 with controls on age, sex, US region, and several comorbidities. Rates of medical complications within 90 days and prosthesis-related complications within 2 years were queried. The number of patients with an opioid claim within 0 to 30 days and subsequent opioid claim(s) during the 90-day global period were obtained to assess rates of prolonged opioid use after arthroplasty. Rates of postoperative complications and opioid claims were compared using logistic regression.

Results:

Patients with prior HA exhibited significantly lower rates of readmission (5.6% vs 7.3%; odds ratio [OR], 0.72), pulmonary embolism (0.2% vs 0.6%; OR, 0.45), urinary tract infection (3.1% vs 4.0%; OR, 0.75), and blood transfusion (3.6% vs 6.1%; OR, 0.55). The prior HA cohort also exhibited a significantly lower rate of prosthetic joint infection at 1 year postoperatively (0.6% vs 1.3%; OR, 0.50). Rates of dislocation, periprosthetic fracture, mechanical complications, and aseptic revision arthroplasty were statistically comparable between the cohorts within 2 years. The prior HA cohort was significantly less likely to file persistent opioid claims after 30 days postoperatively, including between 31 and 60 days (27.2% vs 33.1%; OR, 0.74) and 61 to 90 days (16.2% vs 20.9%; OR, 0.71).

Conclusion:

After elective THA, patients with prior HA exhibited significantly lower rates of medical complications and prolonged opioid claims within 90 days and prosthetic joint infection at 1 year. Rates of all other prosthesis-related complications within 2 years were statistically comparable.

Hip Arthroscopy Improves Outcomes With Moderate Conversion to Total Hip Arthroplasty Rates in Patients Aged 50 Years or Older: A Systematic Review

PURPOSE

The purpose of this systematic review was to assess the indications, outcomes, and complications of hip arthroscopy in individuals 50 years of age or older over the past 5 years.

METHODS

The electronic databases PUBMED, MEDLINE, and EMBASE were searched on March 3, 2022, for studies assessing the use of primary hip arthroscopy for patients aged 50 years or older from the past 5 years. The Methodological Index for Non-randomized Studies (MINORS) was used to assess study quality. Data are presented descriptively.

RESULTS

Overall, 17 studies were included, consisting of 6,696 patients (37.5%) with a mean age of 61.4 ± 5.0 years and a median follow-up of 24 months (range: 1.4-70.1). Indications for hip arthroscopy in patients aged 50 years or older were unspecified/undefined (93.8%), mixed pathology (i.e., combined femoroacetabular impingement [FAI], labral tear, osteoarthritis, etc.) (2.7%), and FAI (2.6%). Eleven studies demonstrated significant improvement in functional outcome scores from baseline to final follow-up. Of the 6 studies that compared outcomes across multiple age groups, 3 demonstrated significantly worse functional outcomes, and 2 demonstrated significantly higher rates of conversion to THA for older patients compared to younger patients. Lastly, the overall complication rates ranged from 0 to 38.3%. The rate of conversion to THA ranged from 0 to 34.6%, occurring between 6 and 60 months postoperatively.

CONCLUSIONS

Hip arthroscopy for patients aged 50 years or older yields significant improvements in patient-reported outcomes postoperatively compared to baseline, with a moderate rate of conversion to THA (range: 0 to 34.6%). Clinicians should consider patient history (e.g., imaging, comorbidities, etc.) and values when electing for hip arthroscopy in the older population.

LEVEL OF EVIDENCE

IV, systematic review of Level III and IV studies.

Increased Readmission Rates but No Difference in Complication Rates in Patients Undergoing Inpatient Versus Outpatient Hip Arthroscopy: A Large Matched-Cohort Insurance Database Analysis

Purpose

Methods

Results

Conclusions

Level of Evidence

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

Level III, retrospective comparison study.

Editorial Commentary: Hip Arthroscopy for Patients With Decreased Center-Edge Angle and Bipolar Cartilage Lesions Is Associated With Early Conversion to Total Hip Arthroplasty

The utilization of hip arthroscopy to treat femoroacetabular impingement has continued to grow year after year. Clinical studies and cost-effectiveness analyses have repeatedly shown the benefits of hip arthroscopy in improving quality of life, offering much promise to this patient population. Through years of research, a more comprehensive understanding of impingement pathologies has brought improving surgical techniques. However, predictors of poor outcomes are still not entirely understood. Although many patients attain significant relief, some patients do not attain meaningful improvement. Meaningful improvement can be found even years after hip arthroscopy, but this is a long road for patients who do not find sustained relief. Thus, as with defining appropriate indications for hip arthroscopy, it is equally important to identify factors that may instead suggest alternative treatment regimens for patients with hip pathology who may not benefit from arthroscopic intervention. However, rather than exclude large groups entirely based on the presence of certain factors such as increased age or arthritis, the goal should be to understand the nuances among patients in these higher-risk groups to identify those who may still find success with hip arthroscopy.

Comparison of early outcomes of arthroscopic labral repair or debridement

Aims

This study uses prospective registry data to compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum.

Methods

Data on adult patients who underwent arthroscopic labral debridement or repair between 1 January 2012 and 31 July 2019 were extracted from the UK Non-Arthroplasty Hip Registry. Patients who underwent microfracture, osteophyte excision, or a concurrent extra-articular procedure were excluded. The EuroQol five-dimension (EQ-5D) and International Hip Outcome Tool 12 (iHOT-12) questionnaires were collected preoperatively and at six and 12 months post-operatively. Due to concerns over differential questionnaire non-response between the two groups, a combination of random sampling, propensity score matching, and pooled multivariable linear regression models were employed to compare iHOT-12 improvement.

Results

A total of 2,025 labral debridements (55%) and 1,659 labral repairs (45%) were identified. Both groups saw significant (p < 0.001) EQ-5D and iHOT-12 gain compared to preoperative scores at 12 months (iHOT-12 improvement: labral repair = +28.7 (95% confidence interval (CI) 26.4 to 30.9), labral debridement = +24.7 (95% CI 22.5 to 27.0)), however there was no significant difference between procedures after multivariable modelling. Overall, 66% of cases achieved the minimum clinically important difference (MCID) and 48% achieved substantial clinical benefit at 12 months.

Conclusion

Both labral procedures were successful in significantly improving early functional outcome following hip arthroscopy, regardless of age or sex. Labral repair was associated with superior outcomes in univariable analysis, however there was no significant superiority demonstrated in the multivariable model. Level of evidence: III Cite this article: Bone Jt Open 2022;3(4):291–301.

Satisfaction, functional outcomes and predictors in hip arthroscopy: a cohort study

INTRODUCTION

Hip arthroscopy is not always successful, leading to high rates of total hip arthroplasty (THA) after arthroscopy. The aim of this study was to identify risk factors for THA, revision arthroscopy and low patient satisfaction and to compare outcomes of the different procedures of primary hip arthroscopy.

METHODS

A total of 91 primary hip arthroscopy procedures in 90 patients (66% female) were analysed. Data were gathered from patient files and a questionnaire was sent to patients including the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), modified Harris Hip Score (mHHS), the EuroQol 5-dimension and questions about return to sports, satisfaction and pain before and after surgery. Using regression analyses, predictive factors for the outcomes were identified.

RESULTS

After a mean of 1.6 years, 4 patients (4%) underwent revision arthroscopy and 10 (11%) a THA. Of the responders (62%), 66% of the patients was satisfied to very satisfied about the surgery. Mean mHHS score was 75.3 (SE 1.9) and the mean WOMAC score was 81.0 (SE 2.8). Return to sports rate was 58%. A higher age was a significant predictor for lower satisfaction (p = 0.008) and a longer duration of symptoms was a significant predictor for worse mHHS outcome scores (p = 0.005).

CONCLUSION

A higher age is a predictor for a lower satisfaction and a longer duration of symptoms before surgery has a negative influence on functional outcome. No risk factors for THA or revision arthroscopy were found and there were no significant differences in outcome measurements between the performed surgeries.

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.

Machine Learning Model Identifies Increased Operative Time and Greater BMI as Predictors for Overnight Admission After Outpatient Hip Arthroscopy

Purpose

The purposes of this study were to identify patient characteristics and risk factors for overnight admission following outpatient hip arthroscopy and to develop a machine learning algorithm that can effectively identify patients requiring admission following elective hip arthroscopy.

Methods

A retrospective review of a prospectively collected national surgical outcomes database was performed to identify patients who underwent elective outpatient hip arthroscopy from 2006 to 2018. Patients admitted overnight postoperatively were identified as those with length of stay of 1 or more days. Models were generated using random forest (RF), extreme gradient boosting (XGBoost), adaptive boosting (AdaBoost), elastic net penalized logistic regression, and an additional model was produced as a weighted ensemble of the four final algorithms.

Results

Overall, 1,276 patients were included. The median age was 43 years, and 64.2% (819) were female. Of the included patients, 109 (8.5%) required an overnight stay following elective outpatient hip arthroscopy. The most important factors for inpatient admission were increasing operative time, general anesthesia, age extremes, male gender, greater body mass index (BMI), American Society of Anesthesiologists classification >1, and the following preoperative lab values outside of normal ranges: sodium, platelet count, hematocrit, and leukocyte count. The ensemble model achieved the best performance based on discrimination assessed via internal validation (area under the curve = .71), calibration, and decision curve analysis. The model was integrated into a Web-based open-access application able to provide both personalized predictions and explanations.

Conclusion

A machine learning algorithm developed based on preoperative features identified increasing operative time, age extremes, greater BMI, sodium, hematocrit, platelets, and leukocyte count as the most important variables associated with inpatient admission with fair validity.

Association of Preoperative Opioid Use With Complication Rates and Resource Use in Patients Undergoing Hip Arthroscopy for Femoroacetabular Impingement

Background

Preoperative opioid use has been shown to be a negative predictor of patient outcomes, complication rates, and resource utilization in a variety of different orthopaedic procedures. To date, there are no studies investigating its effect on outcomes after hip arthroscopy in the setting of femoroacetabular impingement (FAI).

Purpose

To determine the association of preoperative opioid use with postoperative outcomes after hip arthroscopy in patients with FAI.

Study Design

Cohort study; Level of evidence, 3.

Methods

The Truven Health MarketScan Commercial Claims and Encounters Database was queried for all patients who underwent hip arthroscopy for FAI between 2011 and 2018. Opioid prescriptions filled in the 6 months preceding surgery were queried, and the average daily oral morphine equivalents (OMEs) in this period were computed for each patient. Patients were divided into 4 cohorts: opioid naïve, <1 OME per day, 1 to 5 OMEs per day, and >5 OMEs per day. Postoperative 90-day complications, health care utilization, perioperative costs, postoperative opioid use, and 1- and 3-year revision rates were then compared among cohorts.

Results

A total of 22,124 patients were ultimately included in this study; 31.2% of these patients were prescribed opioids preoperatively. Overall, the percentage of preoperative opioid-naïve patients increased from 64.5% in 2011 to 78.9% in 2018. Patients who received preoperative opioids had a higher rate of complications, increased resource utilization, and increased revision rates. Specifically, on multivariate analysis, patients taking >5 OMEs per day (compared with patients who were preoperatively opioid naïve) had increased odds of a postoperative emergency department visit (Odds Ratio, 2.23; 95% confidence interval [CI], 1.94-2.56; P < .001), 90-day readmission (OR, 2.25; 95% CI, 1.77-2.87; P < .001), increased acute postoperative opioid use (OR, 25.56; 95% CI, 22.98-28.43; P < .001), prolonged opioid use (OR, 10.45; 95% CI, 8.92-12.25; P < .001), and 3-year revision surgery (OR, 2.14; 95% CI, 1.36-3.36; P < .001). Perioperative adjusted costs were increased for all preoperative opioid users and were highest for the >5 OMEs per day cohort ($6255; 95% CI, $5143-$7368).

Conclusion

A large number of patients with FAI are prescribed opioids before undergoing hip arthroscopy, and use of these pain medications is associated with increased health care utilization, increased costs, prolonged opioid use, and early revision surgery.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

III, cross-sectional study.

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.

Hip arthroscopy for hip osteoarthritis is associated with increased risk for revision after total hip arthroplasty

BACKGROUND

It has not been determined yet whether hip arthroscopy (HA) leads to adverse outcomes after total hip arthroplasty (THA). The purpose of this study was to (1) determine 2-year conversion rate of HA done for osteoarthritis (OA) to THA and (2) explore the relationship between HA performed in patients with hip osteoarthritis and the risk of revision THA within 2 years of index arthroplasty.

METHODS

Data was collected from the Medicare Standardized Analytic Files insurance database using the PearlDiver Patient Records Database from 2005-2016. Patients were stratified into 2 groups based upon a history of hip arthroscopy prior to THA.

RESULTS

The 2-year conversion to THA rate for hip arthroscopy in patients with OA was 68.4% (95% CI, 66.2-70.6%). Multivariate analysis demonstrated that OA patients who underwent HA prior to THA were at an increased risk of revision surgery (OR 3.72; 95% CI, 3.15-4.57; p = 0.012), periprosthetic joint infection (OR 1.86; 95% CI, 1.26-2.77, p = 0.010) and aseptic loosening (OR 2.81; 95% CI, 1.66-4.76; p < 0.001) within 2 years of THA.

CONCLUSIONS

Analysis of a large insurance database found the conversion rate from HA performed in Medicare OA patients to THA within 2 years is unacceptably high. Hip arthroscopy prior to THA also significantly increased the risk of THA revision within 2 years after index THA. These results suggest that arthroscopic hip surgery should not be performed in patients with a diagnosis of OA as conversion rates are high and revision rates post THA are significantly increased.

Utility of Ultrasound-Guided Anesthetic Intra-articular Injection to Estimate the Outcome of Hip Arthroscopy in Patients with Femoroacetabular Impingement Syndrome

Objective

To investigate the effectiveness of ultrasound (US) guided intra‐hip joint injection to estimate the outcome of hip arthroscopy in patients with femoroacetabular impingement (FAI) syndrome.

Methods

Patients with FAI syndrome (n = 60) were prospectively enrolled in our study. Before hip arthroscopy, a mix of 4 mL 2% lidocaine and 4 mL 1% ropivacaine were injected into the hip joint under the guidance of US. The clinical efficacy of the intra‐articular injection was evaluated by comparing the visual analog scale (VAS) and international hip outcome tool 12 (iHOT‐12) results before and after the injection. The outcome of hip arthroscopy was evaluated by iHOT‐12, the modified Harris hip score (MHHS), and the patient's satisfaction 12 months after the operation. The outcome of intra‐articular injection and hip arthroscopy were compared. Factors related to the outcomes of hip arthroscopy were evaluated. The correlation between the efficacy of intra‐hip joint injection and arthroscopy was evaluated.

Results

The VAS of patients decreased from 11.3 ± 7.7 to 3.3 ± 4.5, and the iHOT‐12 increased from 52.1 ± 23.2 to 84.1 ± 18.1 after intra‐articular injection (all P < 0.001). The iHOT‐12 score increased from 52.1 ± 23.2 to 78.9 ± 19.2, and the MHHS increased from 66.5 ± 6.8 to 81.6 ± 8.1 after hip arthroscopy (all P < 0.001). The satisfaction rate of arthroscopy, including very satisfied and effective patients, was 93.3%. Multi‐variable logistic regression showed that only iHOT‐12 improved value after injection was included in the regression formula of satisfaction, with the β of −0.154, standard error of 0.071, Wald value of 4.720, and OR of 0.857 (95%CI 0.746–0.985) (P = 0.03). Significant correlation was detected between iHOT‐12 scores after intra‐articular anesthesia and at 12 months after arthroscopy (r = 0.784, P < 0.001). So was the iHOT‐12 improved value (r = 0.781, P < 0.001) and the iHOT‐12 improved ratio (r = 0.848, P < 0.001). If we had performed arthroscopy only on patients with post‐injection iHOT‐12 score improvement ≥10, the satisfaction rate of arthroscopy would have increased to 96.6%.

Conclusions

US‐guided intra‐hip joint injection may provide a feasible way to estimate the outcome of hip arthroscopy in patients with FAI syndrome, and could be used as a method for indication selection of hip arthroscopy.

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

BACKGROUND

Despite previous reports of improvements for athletes following hip arthroscopy for femoroacetabular impingement syndrome (FAIS), many do not achieve clinically relevant outcomes. The purpose of this study was to develop machine learning algorithms capable of providing patient-specific predictions of which athletes will derive clinically relevant improvement in sports-specific function after undergoing hip arthroscopy for FAIS.

METHODS

A registry was queried for patients who had participated in a formal sports program or athletic activities before undergoing primary hip arthroscopy between January 2012 and February 2018. The primary outcome was achieving the minimal clinically important difference (MCID) in the Hip Outcome Score-Sports Subscale (HOS-SS) at a minimum of 2 years postoperatively. Recursive feature selection was used to identify the combination of variables, from an initial pool of 26 features, that optimized model performance. Six machine learning algorithms (stochastic gradient boosting, random forest, adaptive gradient boosting, neural network, support vector machine, and elastic-net penalized logistic regression [ENPLR]) were trained using 10-fold cross-validation 3 times and applied to an independent testing set of patients. Models were evaluated using discrimination, decision-curve analysis, calibration, and the Brier score.

RESULTS

A total of 1,118 athletes were included, and 76.9% of them achieved the MCID for the HOS-SS. A combination of 6 variables optimized algorithm performance, and specific cutoffs were found to decrease the likelihood of achieving the MCID: preoperative HOS-SS score of ≥58.3, Tönnis grade of 1, alpha angle of ≥67.1°, body mass index (BMI) of >26.6 kg/m2, Tönnis angle of >9.7°, and age of >40 years. The ENPLR model demonstrated the best performance (c-statistic: 0.77, calibration intercept: 0.07, calibration slope: 1.22, and Brier score: 0.14). This model was transformed into an online application as an educational tool to demonstrate machine learning capabilities.

CONCLUSIONS

The ENPLR machine learning algorithm demonstrated the best performance for predicting clinically relevant sports-specific improvement in athletes who underwent hip arthroscopy for FAIS. In our population, older athletes with more degenerative changes, high preoperative HOS-SS scores, abnormal acetabular inclination, and an alpha angle of ≥67.1° achieved the MCID less frequently. Following external validation, the online application of this model may allow enhanced shared decision-making.

Osteoarthrosis, Advanced Age, and Female Sex Are Risk Factors for Inferior Outcomes After Hip Arthroscopy and Labral Debridement for Femoroacetabular Impingement Syndrome: Case Series With Minimum 10-Year Follow-Up

PURPOSE

(1) To determine the cumulative survivorship using the endpoint of total hip arthroplasty (THA) correlated with osteoarthrosis (Tönnis grade ≤ 1 vs Tönnis grade > 1) at a minimum 10-year follow-up and (2) to identify risk factors for THA conversion.

METHODS

This study examined 112 patients who underwent hip arthroscopy for femoroacetabular impingement syndrome (FAIS) between 2007 and 2009. The inclusion criterion was primary hip arthroscopy to treat FAIS with corresponding chondrolabral pathologies. The exclusion criteria were secondary hip pathologies, revision hip arthroscopy, or dysplasia. The mean follow-up period was 11 years. Cumulative survival was estimated by Kaplan-Meier analysis using the endpoint of THA. Risk factors for THA conversion were identified using a multivariate Cox proportional hazards model.

RESULTS

Forty patients underwent THA. The cumulative survivorship rate at 11 years was 86% for patients with a Tönnis grade of 1 or less and 46% for those with a Tönnis grade greater than 1. Osteoarthrosis, advanced age, and female sex were associated with lower hip survival rates. In particular, the risk of THA conversion was 24% higher for patients with an advanced age at the time of surgery, 97% higher for female patients, and 133% higher for hips with a Tönnis grade greater than 1.

CONCLUSIONS

The survivorship rate at a mean 11-year follow-up after arthroscopic FAIS therapy was 86.3% in the group with a Tönnis grade of 1 or less and 46.4% in the group with a Tönnis grade greater than 1. The presence of osteoarthrosis, advanced age, and female sex adversely affected the outcome.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

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.

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.

Hip arthroscopy in France: An epidemiological study of postoperative care and outcomes involving 3699 patients

BACKGROUND

Hip arthroscopy is a surgical procedure that is becoming more and more prevalent in France. Even though indications are now well-established little is still known about patient outcomes. Therefore, the purpose of our retrospective study was to: (1) describe the circumstances in which hip arthroscopies are being performed; (2) study arthroscopy and arthroplasty reoperation rates; (3) assess the incidence of readmissions for complications.

HYPOTHESIS

Hip arthroscopy in France produced similar results to those observed in other countries.

MATERIALS AND METHODS

We conducted a cohort study from January 2008 to December 2014 in the French population using the national hospital discharge database called "Programme de médicalisation des systèmes d'information (PMSI)." We included all admissions that had a hip arthroscopy code and analyzed readmissions for conversion to hip arthroplasty, revision hip arthroscopy and complications (without being able to provide detailed descriptions). Risk factors associated with conversion, revision and readmission for complications were studied after performing a population analysis.

RESULTS

A total of 3,699 patients were included over a period of seven years. The mean age was 40 years, with women being significantly older (mean age of 43 years) than men (38 years) (p<0.05). The number of procedures increased from 240 in 2008 to 702 in 2014. Synovectomies (67.9%; 2514/3699) and surgical bone procedures (acetabuloplasty or femoroplasty) (47.3%; 1751/3699) were the main procedures performed during the primary arthroscopy. In total, 410 patients underwent a conversion to arthroplasty, 231 patients had a revision arthroscopy, and 126 patients suffered a complication. Five years after the index procedure, the conversion rate was 16.3%, revision rate was 8.2%, and readmission rate for a postoperative complication was 5%. The main risk factor associated with conversions was [Hazard ratio (HR) and 95% Confidence Index (CI)] an age between 40 and 79 years during the first arthroscopy [3.04 (2.40; 3.87) compared with the reference class of 25-39 years]. Patients between ages 16 to 24 years during the first arthroscopy (0.35 [0.20; 0.61] compared with the reference class of 25-39 years) had a decreased risk of conversion (HR and 95% CI). The main risk factors associated with revisions were: synovectomies [1.90 (1.34; 2.70)] and surgical bone procedures on the femoral neck and/or the acetabulum [1.82 (1.36; 2.4)]. The risk factor associated with complication-related readmissions was an age greater than 40 years [2.23 (1.43; 3.49)].

CONCLUSION

Unlike the international literature, our study population was largely male. The rates of revision (8.2% after five years) and conversion to arthroplasty (16.3% after five years) were relatively low and comparable to the different international studies. This procedure, which is not widely performed, is growing in popularity, has low morbidity and remains an interesting approach given the revision and conversion rates after five years. The implementation of specific coding for arthroscopic hip procedures and the pathologies to be treated seems warranted.

LEVEL OF EVIDENCE

IV; descriptive epidemiological study.

Femoroacetabular Impingement and Management of Labral Tears in the Athlete

Femoroacetabular impingement and associated labral tearing is a common source of hip pain in athletes. This article reviews the hip joint anatomy and complex interplay between alterations on the femoral and acetabular sides, in addition to evaluation of soft tissue stabilizers and spinopelvic parameters. Symptom management with a focus on arthroscopic treatment of abnormal bony morphology and labral repair or reconstruction is discussed. In select patients with persistent pain who have failed conservative measures, hip arthroscopy with correction of bony impingement and labral repair or reconstruction has yielded good to excellent results in recreational and professional athletes.

Immediate Versus Delayed Hip Arthroscopy for Femoroacetabular Impingement: An Expected Value Decision Analysis

INTRODUCTION

Hip arthroscopy is an increasingly used surgical procedure for both intra- and extra-articular hip pathologies, including femoroacetabular impingement (FAI). Although the arthroscopic approach is known to be preferable to open, the optimal timing of such intervention is unclear. The purpose of this study was to carry out an expected value decision analysis of immediate versus delayed hip arthroscopy for FAI. Its hypothesis is immediate hip arthroscopy is the preferable treatment option.

METHODS

An expected value decision analysis was implemented to systematize the decision-making process between immediate and delayed hip arthroscopies. A decision tree was created with options for immediate and delayed surgeries with utilities characterizing each state obtained from surveying 70 patients. Fold-back analysis was then carried out, calculating expected values by multiplying the utility of each health outcome by the probability of that outcome. Corresponding expected values were then summed to "fold back" the decision tree one layer at a time. This was repeated until overall expected values (0 to 100) for immediate and delayed hip arthroscopies resulted with the higher value indicating the preferable option.

RESULTS

Fold-back analysis demonstrated that immediate hip arthroscopy is the preferred treatment for FAI over delayed with expected values of 78.27 and 72.63, respectively. Restoration of good function after hip arthroscopy was the most notable contributor to this difference. Immediate hip arthroscopy remained superior even as vast adjustments to preoperative physical function were made in one-way sensitivity analysis. Complications of hip arthroscopy leading to total hip arthroplasty were the least notable contributors to overall expected values.

DISCUSSION

This study confirms that immediate surgery is the preferred option when using decision-making analysis combining patient-reported utilities of health outcomes and the probabilities of those outcomes from the literature. This is consistent across a range of estimates of poor function in both the delayed and immediate surgery arms.

Pre-existing osteoarthritis remains a key feature of arthroscopy patients who convert to total hip arthroplasty

OBJECTIVES

To determine the rate of conversion to total hip arthroplasty following ipsilateral hip arthroscopy by a single surgeon in New Zealand and to describe patient-related and surgical characteristics of patients who converted.

METHODS

A retrospective cohort analysis of hip arthroscopy patients with 2 years of minimum follow-up identified the total hip arthroplasty conversion rate using the New Zealand National Joint Registry. Prospective data collected from patients who subsequently converted to hip arthroplasty included: sex, age at arthroscopy, body mass index, side of hip arthroscopy and arthroplasty, duration of symptoms and patient-reported outcome measures. Imaging (Tönnis grade and lateral centre-edge angle) and surgical findings (labral, ligamentum teres and osteochondral pathology) along with the arthroscopic procedures performed were also documented.

RESULTS

Sixty-six out of 1856 (3.56%) primary hip arthroscopies were followed by an ipsilateral hip arthroplasty during the follow-up period (mean 87 ± 29 months). Most patients had pre-existing osteoarthritis and/or chondral lesions (n=51). Dysplasia and over-resection of the acetabulum were also identified as contributing factors.

CONCLUSION

Conversion rate by a high-volume surgeon in New Zealand was relatively low. Most patients had pre-existing osteoarthritis and/or chondral lesions that became apparent at arthroscopy. Dysplasia is also a factor to be cautious of when selecting patients for arthroscopy. Acetabular resection must be approached cautiously.

LEVEL OF EVIDENCE

Level IV.

What Is the Survivorship After Hip Arthroscopy for Femoroacetabular Impingement? A Large-database Study

BACKGROUND

Patients with femoroacetabular impingement (FAI) may experience lasting clinical improvement after hip arthroscopy; however, some patients will still eventually undergo early conversion to THA due to unresolved symptoms and progression of arthritis. However, the risk of this has been only incompletely characterized in prior studies.

QUESTIONS/PURPOSES

Using a large healthcare claims database over a 5-year period (2011-2016), we asked: (1) What is the survivorship free from THA after arthroscopic osteoplasty performed for FAI? (2) What identifiable demographic factors and patient characteristics are associated with early conversion to THA after hip arthroscopy performed for FAI?

METHODS

We included all patients who underwent hip arthroscopy for FAI, between the ages of 12 years and 63 years, with 3 months of claims data before hip arthroscopy and minimum 2-year follow-up. A total of 4730 hip arthroscopy patients from 2011 to 2014 were retrieved from a US commercial claims database. Hip arthroscopy incidence doubled over time from 1.2 to 2.1 persons per 100,000. Temporal trends, patient demographics, diagnoses at time of arthroscopy, and patient comorbidities were retrieved and logistic regression performed. Survivorship analysis on 11,323 patients (lifting the 2-year follow-up requirement) was also performed to identify independent variables associated with early risk of conversion to THA.

RESULTS

In patients undergoing hip arthroscopy for FAI, the overall proportion of conversion to THA within 2 years after hip arthroscopy was 7% (338 of 4730). After controlling for confounding variables such as sex, obesity, and depression, we found the following were independently associated with increased odds of conversion to THA: older age (odds ratio 1.08 [95% CI 1.01 to 1.10]; p < 0.001), osteoarthritis (OR 2.91 [95% CI 2.27 to 3.77]; p < 0.001), joint inflammation (OR 1.89 [95% CI 1.16 to 3.09]; p = 0.01), and a history of opioid use (OR 2.17 [95% CI 1.69 to 2.79]; p < 0.001). Survivorship analysis similarly revealed that older age (hazard ratio 1.08 [95% CI 1.07 to 1.09]; p < 0.001), osteoarthritis (HR 2.53 [95% CI 2.13 to 3.01]; p < 0.001), joint inflammation (HR 1.53 [95% CI 1.10 to 2.11]; p = 0.01), a history of opioid use (HR 2.02 [95% CI 1.71 to 2.38]; p < 0.001), and smoking (HR 1.55 [95% CI 1.14 to 2.11]; p = 0.005), were independently associated with increased odds of conversion to THA within 2 years after hip arthroscopy for FAI.

CONCLUSIONS

Although the findings of this study are limited and should not be taken in isolation, patients with FAI who are older, carry diagnoses of inflammatory or degenerative articular disease, or who use opioids or smoke should be counseled about a potentially increased risk of undergoing early conversion to THA after hip arthroscopy. Future studies to further examine the effect of these diagnoses in prospectively collected cohorts, incorporating radiographic and patient-reported outcome measures, are needed.

LEVEL OF EVIDENCE

Level III, prognostic study.

Is Labral Size Predictive of Failure With Repair in Hip Arthroscopy?

PURPOSE

To assess whether labral size is predictive of labral repair failure or shows an association with patient outcomes after hip arthroscopy.

METHODS

We performed a retrospective chart review of patients who underwent arthroscopic hip labral repair. Labral size was measured in 4 quadrants with an arthroscopic probe. The average size across torn labral segments was assessed for failure as determined by the change in patient-reported outcomes, the rate at which subjects achieved the minimal clinically important difference and patient acceptable symptomatic state, and the need for additional surgery. Outcomes were evaluated for any continuous correlation as well as significant differences between the middle 50% of labral sizes and classes of labral sizes derived from upper and lower quartile and decile ranges. Included hips were those from patients aged between 18 and 55 years with 2-year postoperative follow-up and lateral center-edge angles between 25° and 40°.

RESULTS

The study included 571 hips. Labral width did not show a significant difference between hips requiring revision and those not requiring revision (P = .4054). No significant correlation was found between labral width and the change in the International Hip Outcome Tool 12 score (R² = 0.05780), modified Harris Hip Score (R² = 0.19826), or Nonarthritic Hip Score (R² = 0.23543) from preoperatively to 2 years postoperatively. Hips with labral sizes in the upper decile of our cohort showed significantly decreased improvement in the International Hip Outcome Tool 12 score (P = .0287) and Nonarthritic Hip Score (P = .0490) compared with the middle 50% of labral sizes. No statistically significant difference was found in the rate at which the groups achieved the minimal clinically important difference or patient acceptable symptomatic state.

CONCLUSIONS

Hypertrophic labra in the largest 10th percentile showed lower postoperative outcome scores. However, no detectable clinical benefit was found in terms of patient-perceived clinical difference or acceptable symptomatic state. For most patients, labral size does not appear to significantly alter patient outcomes or the need for arthroplasty.

LEVEL OF EVIDENCE

Level IV, retrospective 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.

Outcomes of Hip Arthroscopy for Femoroacetabular Impingement in Chinese Patients Aged 50 Years or Older

Objective

To investigate the outcomes of hip arthroscopy for femoroacetabular impingement (FAI) in patients over the age of 50 years.

Method

This is a therapeutic case series study. A total of 27 FAI patients over the age of 50 years who met inclusion and exclusion criteria and were being followed up for at least 2 years in the orthopaedics department at our hospital between January 2015 and October 2017 were recruited for a prospective analysis on the outcomes of hip arthroscopy. All patients underwent unilateral surgery. Of the patients included, there were 15 men and 12 women, who were aged 50–74 years old (57 ± 6.4 years). The outcomes were assessed using the visual analog scale (VAS), the modified Harris hip score (mHHS), and the International Hip Outcome Tool (iHOT‐12).

Results

A total of 27 patients were followed up for at least 2 years. The postoperative center‐edge angle, the alpha angle, and the offset decreased significantly compared with preoperative measurements (P < 0.01). The mHHS before surgery and at 1 year and 2 years after surgery was 62.19 ± 7.47, 86.70 ± 5.80, and 87.89 ± 5.08, respectively; iHOT‐12 scores were 30.44 ± 4.22, 73.56 ± 3.89, and 73.77 ± 3.72, respectively; VAS scores were 6.07 ± 0.78, 1.93 ± 0.73, and 1.59 ± 0.64, respectively. As compared with the condition before surgery, there was a significant improvement in the mHHS, iHOT‐12, and VAS scores at 1 year and 2 years after surgery (P < 0.01). The mHHS score at 2‐year follow up after surgery was higher than that at 1 year after surgery, and the difference observed was statistically significant (P = 0.04). One patient with severe acetabular and femoral cartilage damage underwent total hip replacement 11 months after surgery.

Conclusion

Hip arthroscopy considerably improved hip symptoms and function in Chinese FAI patients aged 50 years or older who did not have severe radiographic osteoarthritis. The conversion to THA and complications were low. Strict surgical indications and appropriate surgical strategies lay the foundation for satisfactory postoperative results in elderly patients with FAI.

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.].

Midterm-clinical Outcomes after Hip Arthroscopy in Middle-aged Patients with Early Osteoarthritis

Purpose

Although the number of hip arthroscopies is rapidly increasing in non-elderly patients, outcomes of this procedure in middle-aged patients are not well documented or clearly understood. The purpose of this study was to evaluate the clinical and radiological outcomes after hip arthroscopy in middle-aged patients with early osteoarthritis.

Materials and Methods

This retrospective study analyzed 189 patients with early osteoarthritis of various diagnoses aged 40 years or older who underwent hip arthroscopy between January 2010 and December 2015. Clinical (e.g., modified Harris hip score [mHHS], hip outcome score-activities of daily living [HOS-ADL], visual analogue scale [VAS] for pain, range of motion) and radiological (change of Tönnis grade) outcomes were assessed at a minimum of 3-year follow-up.

Results

The mean preoperative and final mHHS and HOS-ADL improved from 61.2 and 60.6 to 79.5 and 81.8, respectively, while the VAS pain score decreased from 6.3 to 3.2 (P<0.001). Although the mean range of internal rotation and flexion increased from 14.2 and 100.7° preoperatively to 30.4 and 110.6° at 1-year postoperatively, they decreased slightly to 27.4 and 105.4° at the final follow-up, respectively. Eight cases (4.2%) underwent revision arthroscopic surgery and three cases (1.6%) were converted to total hip arthroplasty.

Conclusion

Patients with early-stage osteoarthritis of various diagnoses achieved improved clinical outcomes. Therefore, using hip arthroscopy in middle-aged patients with early osteoarthritis, it is possible to achieve good surgical options.

Nonoperative Management of Hip Labral Tears Yields Similar Total Hip Arthroplasty Conversion Rate to Arthroscopic Treatment

BACKGROUND

Arthroscopic treatment of hip labral tears has increased significantly in recent years. There is limited evidence comparing nonoperative management to arthroscopic treatment. The purpose of this study is to evaluate the progression to total hip arthroplasty (THA), as well as the cost associated with arthroscopic management of labral tears compared to nonoperative treatment.

METHODS

The Humana claims database was queried from 2007 through 2016. International Classification of Diseases and Current Procedural Terminology codes were used to identify patients with hip labral tears and hip arthroscopy and THA procedures. Two cohorts were created: a nonoperative group and an operative group. Following propensity score matching, the rate of conversion and time to THA conversion were calculated. Cost was calculated using the total cost reimbursed for encounters within 6 months. Continuous variables were analyzed using Student t-test and Mann-Whitney test, and categorical variables were analyzed using chi-square test.

RESULTS

After propensity matching, 864 patients were included in the analysis. The conversion rate to THA in the operative group (6.7%) and the nonoperative group (5.3%) was not statistically different (P = .391). The operative group had a longer time to THA (21.5 ± 16.8 months) than the nonoperative group (15.9 ± 19.5 months; P = .044). The cost for the operative group was significantly higher ($14,266.55 ± $7187.96) compared to the nonoperative group ($2941.96 ± $2664.00; P < .001).

CONCLUSION

This study did not find a difference in the rate of conversion to THA for operative vs nonoperative groups. Time to THA in the operative group was longer, however, at the expense of higher costs.

A Shift in Hip Arthroscopy Use by Patient Age and Surgeon Volume: A New York State-Based Population Analysis 2004 to 2016

PURPOSE

To perform a population-level analysis of the shifts in use of hip arthroscopy by different age groups and to describe the proportion of hip arthroscopy procedures performed by high-volume surgeons.

METHODS

The Statewide Planning and Research Cooperative System database was combined with New York State census data to calculate changes in annual hip arthroscopy incidence by age and gender (2004-16). Annual (January to January) surgeon volumes were calculated and stratified into 4 thresholds that have been associated with significant differences in revision hip surgery rates to calculate changes in hip arthroscopy rates by surgeon volume over time.

RESULTS

There was a 495% increase in hip arthroscopies from 2004 to 2016, from 2.35 to 15.47 per 100,000 residents in New York State. The largest increase was in the 10-19 years age group-a 2,150% increase for female patients (= 1.26, P < .001) and a 1,717% increase for male patients (incident rate ratio = 1.21, P < .001). The number of labral repairs performed with femoroplasty increased 52.8% (P < .001). The number of hip arthroscopy surgeons increased from 3.4 to 6.5 per 1 million residents. The number of hip arthroscopies performed by high-volume surgeons increased from 0% in 2004 to 24.7% in 2016.

CONCLUSIONS

The use of hip arthroscopy has increased over the past 10 years, especially in the adolescent population ages 10-19. Over the same time period, there has been an emergence of high-volume hip arthroscopy surgeons and an increased proportion of procedures performed by these surgeons. Patients of high-volume surgeons tend to be younger, while lower volume surgeons tend to have older patients.

LEVEL OF EVIDENCE

Level IV, case series.

Hip Arthroplasty After Hip Arthroscopy: Are Short-term Outcomes Affected? A Systematic Review of the Literature

PURPOSE

To systematically review the published literature regarding intraoperative measures, patient-reported outcomes, and complications of total hip arthroplasty (THA) in patients with or without a history of prior hip arthroscopy.

METHODS

PubMed and Cochrane Library databases were searched for all publications regarding patients who had undergone a THA after a prior ipsilateral hip arthroscopy. Included studies were comparative in nature and included postoperative outcome measures. Excluded studies were opinion articles, review articles, cadaveric studies, case reports, or technique articles. Patient demographics, surgical outcomes, complications, and patient-reported outcome measures (PROMs) were recorded. This study was performed at the American Hip Institute.

RESULTS

Eight studies were included in this systematic review. These included 305 hips with a THA following a prior hip arthroscopy, with 502 matched control hips. Mean time for conversion from prior hip arthroscopy was 23 months and mean follow up was 35.9 versus 36.1, for the prior arthroscopy and control groups respectively. No significant differences were found regarding intraoperative measures and PROMs. There was no difference in rate of revisions at latest follow up. However, there was a trend toward higher rates of dislocations and infections in the prior hip arthroscopy group.

CONCLUSION

The short-term PROMs of those who underwent total hip arthroplasty with a prior history of an ipsilateral hip arthroscopy are comparable to those of patients undergoing primary THA. Although a conclusion could not be made regarding differences in complication rates between patients with a history of prior arthroscopy and patients undergoing primary THA, it is still imperative to consider the possible implications of a prior hip procedure on postoperative stability and infection rates. In summary, hip arthroplasty following a prior hip arthroscopy is a safe procedure with comparable short-term outcomes to primary arthroplasty.

LEVEL OF EVIDENCE

Level III, systematic review.

Validation of a Risk Calculator for Conversion of Hip Arthroscopy to Total Hip Arthroplasty in a Consecutive Series of 1400 Patients

BACKGROUND

A previously published calculator used age, preoperative modified Harris Hip Score, femoral anteversion, preoperative lateral center-edge angle, revision surgery, and acetabular and femoral cartilage damage to provide risk estimates for conversion rate of hip arthroscopy to total hip arthroplasty (THA). Validation for this calculator has not been established. The purpose of this study is to (1) validate the previously published hazard ratios for the predictor factors in a new cohort of hip arthroscopies with minimum 2-year follow-up and (2) determine the accuracy of the calculator at determining conversion rates to THA at 2 and 4 years of follow-up.

METHODS

Hazard ratios for THA conversion were calculated using data between February 2008 and November 2016 and compared to the previously published results, which comprised the training set. Actual conversion to THA data was used to evaluate the accuracy of the calculator.

RESULTS

Of the 1400 patients examined, THA conversion occurred in 101 (7.2%) patients at an average of 28.4 ± 22.9 months (0.2-115.8) after hip arthroscopy. The hazard ratios for the validation set compared to the training set were as follows: age 1.06 versus 1.06; modified Harris Hip Score 0.97 versus 0.98; femoral anteversion 0.99 versus 0.97; lateral center-edge angle 0.98 versus 0.93; and revision surgery 1.77 versus 2.40. Accuracy of the risk calculator at 2 years was 75% (Harrell C-statistic 0.806) and at 4 years was 73% (C-statistic 0.797).

CONCLUSION

This study found 75% and 73% accuracy at 2 and 4 years respectively in calculating risk of conversion of hip arthroscopy to THA using a previously published calculator. As this calculator relies on intraoperative data, the major benefit it provides is information regarding patient prognosis postoperatively. Furthermore, it could potentially enable the surgeon, after receiving proper surgical consent, to decide on immediate conversion to THA.

LEVEL OF EVIDENCE

III, retrospective cohort.

Primary labral reconstruction in patients with femoroacetabular impingement, irreparable labral tears and severe acetabular chondral defects decreases the risk of conversion to total hip arthroplasty: a pair-matched study

In the presence of severe acetabular cartilage defects, the benefits of labral reconstruction (RECON) versus labral resection (RESEC) have not been determined. Prospectively collected data between October 2008 and December 2016 were retrospectively reviewed. Inclusion criteria were hip arthroscopy, acetabular Outerbridge grade III/IV, irreparable labral tears that underwent RECON or RESEC, and minimum 2-year postoperative measures for the modified Harris Hip Score, Non-Arthritic Hip Score, Hip Outcome Score-Sports Specific Subscale, International Hip Outcome Tool, Patient Satisfaction and Visual Analogue Scale for pain. Exclusion criteria included Tönnis grade >1, previous hip conditions or previous ipsilateral hip surgeries. A 1:1 matched-pair analysis was performed based on age ±5 years, sex, body mass index ±5 kg/m², Tönnis grade, acetabular microfracture, femoral Outerbridge grade (0 or I compared with II, III or IV). Relative risk (RR) and conversion rate to total hip arthroplasty (THA) were calculated. A total of 38 RECON hips were successfully matched. Both groups demonstrated significant improvements in patient-reported outcomes (PROs). THA conversion was 5.3% and 21.1% for the RECON and RESEC groups, respectively (P = 0.04). RECON was four times less likely to require THA conversion than the RESEC group (RR=4.0; 95% CI 0.91-17.63). In the setting of primary arthroscopic management of femoroacetabular impingement, irreparable labral tears and acetabular chondral lesions of Outerbridge III/IV, patients that underwent RECON and RESEC experienced significant improvement in PROs at minimum 2-year follow-up, and these functional scores were comparable when groups were matched. However, RR and rate to THA conversion were significantly higher in the RESEC group.

Clinical and Radiographic Predictors for Unsalvageable Labral Tear at the Time of Initial Hip Arthroscopic Management for Femoroacetabular Impingement

BACKGROUND

The acetabular labrum plays important roles in proprioception, nociception, synovial fluid seal effect, and static and dynamic joint stability and as a shock absorber. Clinical and radiographic risk factors for unsalvageable labral tear in femoroacetabular impingement (FAI) are not well established.

PURPOSE

To identify predictors of unsalvageable labral tear during initial hip arthroscopic management of FAI.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Patients were included who underwent primary hip arthroscopic treatment for FAI between March 2009 and March 2014. Patients were excluded who had <2-year follow-up, underwent bilateral surgery, or had a history of surgery, osteoarthritis (Tönnis grade 2 or 3), and other diagnoses, including lateral center-edge angle <25° diagnosed as developmental hip dysplasia. Patients were divided into 2 groups according to their labral condition: reconstruction and refixation. Unsalvageable labral tear was defined as any irreparable labral tear, including severe degenerative tear, frayed labrum, labral ossification, flattened labrum, and failed prior repair during surgery. Univariate and multivariate analyses identified risk factors for segmental labral reconstruction. Patient-reported outcome scores and postoperative revision rates were also assessed.

RESULTS

Twenty-five hips (18 male, 7 female) and 126 hips (65 male, 61 female) were included in the reconstruction and refixation groups, respectively. The mean ± SD ages were 52.6 ± 15.0 and 36.5 ± 16.1 years in the reconstruction and refixation groups, respectively. In the reconstruction group, the mean modified Harris Hip Score significantly improved from 67.3 ± 14.9 preoperatively to 95.0 ± 8.1 at final follow-up (P < .001), and the mean Nonarthritic Hip Score improved from 63.0 ± 18.3 preoperatively to 89.5 ± 10.1 at final follow-up (P < .001). In the refixation group, the mean modified Harris Hip Score significantly improved from 69.2 ± 18.6 preoperatively to 93.0 ± 11.2 at final follow-up (P < .001), and the mean Nonarthritic Hip Score improved from 60.7 ± 18.8 preoperatively to 88.6 ± 15.0 at final follow-up (P < .001). No significant difference was noted in patient-reported outcome scores and revision hip arthroscopy rates. The rate of conversion of total hip arthroplasty was higher in the reconstruction group than in the refixation group. Risk factors for unsalvageable labral tear were age ≥45 years (odds ratio [OR], 8.83; P < .007), body mass index ≥23.1 kg/m² (OR, 13.05; P < .001), and vertical center anterior angle ≥36° (OR, 19.03; P < .001). Furthermore, in this study, unsalvageable labral tears were present in cases with at least 2 of the 3 risk factors.

CONCLUSION

Age ≥45 years, body mass index ≥23.1 kg/m², and vertical center anterior angle ≥36° are risk factors for unsalvageable labral tear at initial hip arthroscopic surgery for patients with FAI.

Impacto femoroacetabular – Fatores associados à presença de lesões profundas da junção condrolabral

Objective  The purpose of the present study was to evaluate factors associated with the presence of deep chondral lesions (Konan/Haddad grades III and IV) in patients submitted to hip arthroscopy to treat femoroacetabular impingement (FAI).

Method  This was a prospective, cross-sectional study of a series of 125 consecutive hip arthroscopies performed between May 2016 and May 2017. After applying the exclusion criteria, 107 hips of 92 patients submitted to surgical treatment for mixed and CAM FAI were analyzed. For purposes of analysis, the present study considered groups with lesions considered mild and deep, which were associated with symptom score, lateral coverage angle, α angle, age, gender, and radiological classification of arthrosis. Results with a p -value < 0.05 were considered statistically significant.

Results  Patients whose hips had lesions considered deep had significantly higher nonarthritic hip scores (NAHSs) than those whose hips presented lesions considered mild or who did not present chondral lesions (67.9 ± 19.4 versus 57.0 ± 21.9, p  = 0.027). The prevalence of deep lesions was higher in hips with Tonnis 1 compared with hips with Tonnis 0: 15 (55.6%) versus 10 (12.7%), respectively, p  < 0.001. Men presented a higher prevalence of grades III and IV lesions than women, 23 (34.3%) versus 2 (5.0%), p  = 0.001, and had significantly higher functional scores (65.6 ± 19.6 versus 49.3 ± 21.6, p  < 0.001).

Conclusion  Men presented a higher prevalence of deep lesions. Hips classified as Tonnis 1 presented a 4.4-fold higher probability of presenting these lesions. Patients with deep chondrolabral lesions had a better preoperative functional score.

Understanding Preoperative Demographics and Risk Factors for Early Revision Surgery in Patients Undergoing Hip Arthroscopic Surgery: A Large Database Study

BACKGROUND

Hip arthroscopic surgery has become an increasingly common surgical technique to diagnose and treat various hip abnormalities. While increased efficacy has been reported, debate remains regarding appropriate surgical indications. Multiple factors including patient demographics, surgical procedure, and underlying disease have been associated with poor surgical outcomes. Preoperative diagnostic and treatment interventions including physical therapy and injections may affect surgical indications and outcomes.

PURPOSE

To identify patient characteristics and preoperative factors associated with an increased risk of early revision surgery and/or extended postoperative medical care after index hip arthroscopic surgery.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Utah's All Payer Claims Database, a state-mandated registry containing data from all payers, including private insurance, Medicare Advantage, and Medicaid, was queried to identify patients who underwent hip arthroscopic surgery during a 3-year period (January 1, 2013, to December 31, 2015). Demographics, comorbidities, nonoperative care modalities, pain medications, and revision procedures were collected using claims data at 6 months preoperatively and 12 months postoperatively.

RESULTS

A total of 1283 patients who underwent primary hip arthroscopic surgery were analyzed, of whom 57.6% (n = 739) were female. Within 1 year of index surgery, 7.8% and 2.1% of patients underwent revision hip arthroscopic surgery and conversion to total hip arthroplasty (THA), respectively. Patients older than 60 years and male patients were more likely to undergo revision arthroscopic surgery (odds ratio [OR], 0.89; P < .001 and OR, 1.59; P = .04, respectively) and convert to THA (OR, 1.03; P = .01 and OR, 2.25; P = .05, respectively). Preoperative opioid use was significantly associated with increased odds of revision surgery (OR, 1.64; P = .05) and THA (OR, 2.70; P = .03). No significant relationship existed between preoperative physical therapy or intra-articular hip injections and revision hip arthroscopic surgery (OR, 1.20; P = .45 and OR, 1.18; P = .52, respectively) or conversion to THA (OR, 0.89; P = .79 and OR, 0.71; P = .46, respectively).

CONCLUSION

This study showed that predictable patient factors can effectively guide preoperative decision making and may improve prognosis. Certain patient pools require optimization preoperatively, and a subset of patients appears to require additional surgical indications.

Arthroscopic Acetabular Labral Repair in Patients Over the Age of 60 Years: A Matched Case-Control Study

PURPOSE

To report the results of labral repair in a population of patients older than 60 years and compare these with a matched population of younger adults.

METHODS

We compared 21 consecutive patients older than 60 years undergoing labral repair with minimum 1-year follow-up with a contemporaneous group of 21 patients aged 18 to 55 years matched for sex, degree of chondral damage, and associated femoroacetabular impingement or dysplasia.

RESULTS

Follow-up averaged 18.9 months (range, 12-24 months). The average age in the study group was 63.2 years (range, 61-71 years), and 20 patients had femoroacetabular impingement whereas 1 had dysplasia. Of these patients, 19 had acetabular articular damage (grade IV in 2, grade III in 11, grade II in 5, and grade I in 1) and 6 had femoral changes (grade IV in 1 and grade III in 5). The average age in the control group was 35.8 years (range, 20-54 years). We found average improvements of 28.1 points for the modified Harris Hip Score and 37.5 points for the International Hip Outcome Tool score within the study group and 21.2 points for the modified Harris Hip Score and 37.1 points for the International Hip Outcome Tool score within the control group. No statistically significant difference between the 2 groups was noted in the amount of improvement, with statistically and clinically significant improvements noted in both. Two study group patients underwent total hip arthroplasty (THA) at an average of 10 months, with 1 control group THA at 11 months. All 3 patients with conversion to THA had combined grade IV acetabular and grade III femoral damage. No repeated arthroscopies were performed and no complications occurred in either group.

CONCLUSIONS

Patients older than 60 years can benefit from arthroscopic labral repair with improved outcomes, a modest rate of conversion to THA, and a small risk of complications. The results are comparable to those of younger adults. Combined bipolar grade IV and grade III articular damage may be a harbinger of conversion to THA regardless of age.

LEVEL OF EVIDENCE

Level III, comparative therapeutic trial.