Hip Arthroscopic Surgery Research Articles

Outcomes for Treatment of Capsulolabral Adhesions With a Capsular Spacer During Revision Hip Arthroscopy

Background: The presence of adhesions is a common source of pain and dysfunction after hip arthroscopic surgery and an indication for revision surgery. The placement of a capsular spacer in the capsulolabral recess after lysis of adhesions has been developed to treat and prevent the recurrence of adhesions. Purpose: To evaluate patient-reported outcomes (PROs) and survivorship at a minimum of 2 years after revision hip arthroscopic surgery with capsular spacer placement for capsular adhesions. Study Design: Case series; Level of evidence, 4. Methods: Between January 2013 and June 2018, a total of 95 patients (99 hips) aged ≥18 years underwent revision hip arthroscopic surgery for the treatment of capsular adhesions with the placement of a capsular spacer. Overall, 53 patients (56 hips) met the inclusion criteria and had a minimum 2-year follow-up, forming the cohort of this study. Exclusion criteria included confounding metabolic bone diseases (eg, Legg-Calve-Perthes disease, Marfan syndrome), labral deficiency, or advanced osteoarthritis (Tönnis grade 2 or 3). Preoperative and postoperative outcome scores (modified Harris Hip Score [mHHS], Hip Outcome Score–Activities of Daily Living [HOS-ADL], Hip Outcome Score–Sport-Specific Subscale [HOS-SSS], 12-Item Short Form Health Survey [SF-12], and Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]) were collected and compared in addition to the revision rate, conversion to total hip arthroplasty, and patient satisfaction. Results: The mean age of the cohort was 32 ± 11 years, with 32 female hips (57%) and a median number of previous hip arthroscopic procedures of 1 (range, 1-5). The arthroplasty- and revision-free survivorship rate at 2 years was 91%. Overall, 5 patients (6 hips; 11%) underwent revision surgery at a mean of 2.4 ± 1.4 years after capsular spacer placement, with symptomatic capsular defects being the most common finding. There were 4 patients (7%) who converted to total hip arthroplasty. For hips not requiring subsequent surgery (n = 46), there was a significant improvement in outcome scores except for the SF-12 Mental Component Summary, with rates of achieving the minimal clinically important difference of 70%, 70%, and 65% for the mHHS, HOS-ADL, and HOS-SSS, respectively. Conclusion: Capsular spacers, as part of a systematic approach including lysis of adhesions with early and consistent postoperative physical therapy including circumduction exercises, resulted in improved PROs as well as high arthroplasty– and revision-free survivorship (91%) at a minimum 2-year follow-up. Capsular spacers should be considered in revision hip arthroscopic procedures when an adequate labral volume remains but adhesions continue to be a concern.

Arthroscopic Capsular Suture-Lifting Technique for Treating Femoroacetabular Impingement Patients With a High Risk of Postoperative Anterior Instability

With the increasing popularity of hip arthroscopy, postoperative iatrogenic instability due to bony and soft-tissue issues has been noted by more orthopaedic surgeons. Although there is a low risk of serious complications in patients with normal hip joint development even without suturing of the joint capsule, for patients with a preoperative high risk of anterior instability—including those with excessive anteversion of the acetabulum or femur, borderline dysplasia of the hip, and hip arthroscopic revision surgery with an anterior defect of the joint capsule—capsulotomy without repair will result in postoperative anterior instability of the hip joint and related symptoms. Capsular suturing techniques that provide anterior stabilization will be of great help for these high-risk patients and reduce the possibility of postoperative anterior instability. In this Technical Note, we introduce the arthroscopic capsular suture-lifting technique for treating femoroacetabular impingement (FAI) patients with a high risk of postoperative hip instability. In the past 2 years, the capsular suture-lifting technique has been used to treat FAI patients with borderline dysplasia of the hip and excessive femoral neck anteversion, and clinical results have shown that the suture-lifting technique provides a reliable and effective solution for FAI patients with a high risk of postoperative anterior hip instability.

The Reliability of the Tönnis Grading System in Patients Undergoing Hip Preservation

Background: The presence of pre-existing osteoarthritis (OA) has been associated with poor results after hip arthroscopic surgery. There is limited evidence validating the currently available grading systems of hip OA in patients undergoing hip preservation. Purpose/Hypothesis: Our purpose was to evaluate the interobserver and intraobserver reliabilities of 2 grading systems in a group of patients undergoing hip preservation: the Tönnis grading system and a simple 4-choice Likert scale. The hypothesis was that interobserver and intraobserver reliabilities using the Tönnis grading system would be poor among surgeons experienced in hip preservation and that a 4-choice Likert scale would be more reliable. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: A total of 100 hip radiographs were reviewed by 8 experienced hip preservation surgeons. Overall, 2 rounds of reviews were performed, at least 3 weeks apart, assessing for the presence, degree, and/or location of joint space narrowing, joint space asymmetry, subchondral cysts, osteophytes, and sclerosis. The radiographs were assigned a Tönnis grade as well as a Likert grade of OA, reported as none, mild, moderate, or severe. Statistical analysis was conducted to provide Fleiss kappa values with 95% CIs. Agreement was classified as poor for <0.00, slight for 0.00-0.20, fair for 0.21-0.40, moderate for 0.41-0.60, substantial for 0.61-0.80, and almost perfect for >0.80. Results: A total of 50 patients (28 female and 22 male) with a mean age of 42.8 ± 14.2 years (range, 19-70 years) were reviewed. The Tönnis grade demonstrated an interobserver kappa value of 0.30 (95% CI, 0.26-0.34). The Likert grade demonstrated an interobserver kappa value of 0.33 (95% CI, 0.28-0.37). All other measures demonstrated interobserver kappa values classified as slight or fair except for subchondral cysts which was moderate. Intraobserver reliabilities were statistically significantly higher than interobserver reliabilities. Intraobserver reliabilities for both the Tönnis grade (κ = 0.55 [95% CI, 0.51-0.60]) and Likert grade (κ = 0.59 [95% CI, 0.55-0.63]) demonstrated similar kappa values, consistent with moderate agreement. Subchondral cysts demonstrated the strongest interobserver (κ = 0.53) and intraobserver (κ = 0.85) reliabilities. Conclusion: Interobserver and intraobserver reliabilities were fair and moderate, respectively, for grading OA. Given the limited interobserver reliability, caution should be used when interpreting and translating studies that utilize the Tönnis grade or other rating to dictate treatment algorithms.

A Case Study of Post-Operative Rehabilitation from Arthroscopic Hip Surgery for Femoroacetabular Impingement (FAI) and Labral Tear

A Case Study of Post-Operative Rehabilitation from Arthroscopic Hip Surgery for Femoroacetabular Impingement (FAI) and Labral Tear

Endoscopic Excision of Hip Heterotopic Ossification, Plus Indomethacin and Radiation, Is Effective in Treating and Preventing Recurrence

To describe the clinical and patient-reported outcomes of heterotopic ossification (HO) excision as well as the results of a standardized HO prophylaxis protocol among a group of patients who previously underwent open or arthroscopic hip surgery. Patients who developed HO after index hip surgery and were subsequently treated with arthroscopic excision of HO and postoperative HO prophylaxis using 2 weeks of indomethacin and radiation were retrospectively identified. All patients were seen by a single surgeon and were treated with the same arthroscopic technique. Patients were also placed on a regimen of 2 weeks of indomethacin 50 mg and radiation therapy with 700 cGy in one fraction on the first postoperative day. Outcomes assessed included recurrence of HO and conversion to total hip arthroplasty by latest follow-up. Other outcomes included Modified Harris Hip Scores and Non-Arthritic Hip Scores, which were collected preoperatively and at 1-year and 2-year follow-up. There were 5 female and 9 male subjects, with an average age of 39 years (range 22-66) and average body mass index of 27.1 (19.1-37.5). Average follow-up time was 46 months (range 4-136). No patients had experienced HO recurrence by latest follow-up. Only 2 patients converted to total hip arthroplasty, one at 6 months and the other at 11 months postexcision. Average outcome scores improved by 2-year follow-up (average Modified Harris Hip Scores 52.8 improved to 86.5, average Non-Arthritic Hip Scores 49.4 improved to 83.8). Minimally invasive arthroscopic excision of HO and postoperative prophylaxis with combined indomethacin and radiation therapy effectively treats and prevents the recurrence of HO. Level IV, case series, therapeutic.

Combined 3-Dimensional CT and Multidirectional CT Arthrography for Femoroacetabular Impingement and Hip Lesions: A Cross-sectional Study Comparing Imaging and Hip Arthroscopic Surgery Findings.

There is limited research investigating the diagnostic strength of 3-dimensional computed tomography (3D-CT) and multidirectional CT arthrography (CTA) for femoroacetabular impingement (FAI) and related hip lesions. To evaluate the diagnostic strength of combined 3D-CT and CTA in patients with FAI and related hip lesions by comparing it with hip arthroscopic surgery findings. Cohort study (diagnosis); Level of evidence, 2. This study included patients who were suspected of having FAI and related hip lesions and who underwent a combination of 3D-CT and CTA and subsequent hip arthroscopic surgery between December 2013 and December 2017. The CT and intraoperative arthroscopic findings were recorded and compared. The sensitivity, specificity, and accuracy of 3D-CT for FAI and those of CTA for related hip lesions were calculated. A total of 114 patients with 114 hips were included in our study. There were 101 patients with positive findings and 13 patients with negative findings for FAI (including cam, pincer, and combined morphology) according to 3D-CT. The sensitivity, specificity, and accuracy of 3D-CT for FAI were 91.58%, 57.14%, and 89.47%, respectively. The sensitivity, specificity, and accuracy of CTA for labral tears were 94.64%, 100.00%, and 94.73%, respectively. For acetabular cartilage defects, the sensitivity, specificity, and accuracy of CTA were 60.71%, 91.37%, and 76.31%, respectively. For femoral cartilage defects, the sensitivity, specificity, and accuracy of CTA were 82.22%, 76.81%, and 78.94%, respectively. The study results indicated that 3D-CT was able to provide excellent accuracy for FAI compared with hip arthroscopic surgery findings. In addition, multidirectional CTA demonstrated promising diagnostic strength for hip lesions such as labral tears and chondral defects.

Conversion Total Hip Arthroplasty in the Era of Bundled Care Payments: Impacts on Costs of Care

BackgroundConversion hip arthroplasty is defined as a patient who has had prior open or arthroscopic hip surgery with or without retained hardware that is removed and replaced with arthroplasty components. Currently, it is classified under the same diagnosis-related group as primary total hip arthroplasty (THA); however, it frequently requires a higher cost of care. MethodsA retrospective study of 228 conversion THA procedures in an orthopaedic specialty hospital was performed. Propensity score matching was used to compare the study group to a cohort of 510 primary THA patients by age, body mass index, sex, and American Society of Anesthesiologists score. These matched groups were compared based on total costs, implants used, operative times, length of stay (LOS), readmissions, and complications. ResultsConversion THA incurred 25% more mean total costs compared to primary THA (P < .05), longer lengths of surgery (154 versus 122 minutes), and hospital LOS (2.1 versus 1.56 days). A subgroup analysis showed a 57% increased cost for cephalomedullary nail conversion, 34% increased cost for sliding hip screw, 33% for acetabular open reduction and internal fixation conversion, and 10% increased costs in closed reduction and percutaneous pinning conversions (all P < .05). There were 5 intraoperative complications in the conversion group versus none in the primary THA group (P < .01), with no statistically significant difference in readmissions. ConclusionConversion THA is significantly more costly than primary THA and has longer surgical times and greater LOS. Specifically, conversion THA with retained implants had the greatest impact on cost.

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

To compare (a) the change in radiological bony morphology between participants with femoroacetabular impingement (FAI) syndrome who underwent arthroscopic hip surgery compared to physiotherapist-led non-surgical care and (b) the change in radiological bony morphology between participants with FAI syndrome who underwent arthroscopic hip surgery involving cam resection or acetabular rim trimming or combined cam resection and acetabular rim trimming. Maximum alpha angle measurements on magnetic resonance imaging and Hip2 Norm standardized hip measurements on radiographs were recorded at baseline and at 12 months postoperatively. One-way analysis of covariance and independent T tests were conducted between participants who underwent arthroscopic hip surgery and physiotherapist-led non-surgical care. Independent T tests and analysis of variance were conducted between participants who underwent the 3 different arthroscopic hip procedures. Arthroscopic hip surgery resulted in significant improvements to mean alpha angle measurements (decreased from 70.8° to 62.1°) (P value < .001, 95% CI -11.776, -4.772), lateral center edge angle (LCEA) (P value=.030, 95% CI -3.403, -0.180) and extrusion index (P value=0.002, 95% CI 0.882, 3.968) compared to physiotherapist-led management. Mean maximum 1-year postoperative alpha angle was 59.0° (P value=.003, 95% CI 4.845, 18.768) for participants who underwent isolated cam resection. Measurements comparing the 3 different arthroscopic hip procedures only differed in total femoral head coverage (F[2,37]=3.470, P=.042). Arthroscopic hip surgery resulted in statistically significant improvements to LCEA, extrusion index and alpha angle as compared to physiotherapist-led management. Measured outcomes between participants who underwent cam resection and/or acetabular rim trimming only differed in total femoral head coverage.

The traction force of the pulled limb in hip arthroscopic surgery is determined by stiffness coefficient which is significantly related to muscle volume.

To verify the relationship between muscle volume, lateral centre-edge angle (LCEA), alpha angle (AA), body mass index (BMI) and Beighton score with stiffness coefficient (SC). To analyse the difference of traction force at different physical states of hip joint capsule. Thirty-six patients who underwent hip arthroscopy operation were included. The volumes of some related muscles were measured in MRI images by 3D Slicer. We recorded and tested differences in traction force of five joint capsule physical states, including before (State 1) and after joint capsule puncture (State 2), after the establishment of anterolateral and mid-anterior approaches (State 3) and after incision of the joint capsule through these two approaches (States 4, 5). The correlation between muscle volume, BMI, LCEA, AA and SC was verified by Spearman test. Poisson regression was used to explain confounding variables. The average force at State 1 was 531.8N. There were significant differences in traction force between these five states (p < 0.001). There was a significant positive correlation between muscle volumes and SC (p < 0.001). BMI had no correlation with SC (n.s.). The preoperative LCEA of the affected side was correlated with SC (p = 0.043). AA and SC were not correlated (n.s.). The physical states of the hip joint capsule affected traction force. Muscle volume rather than BMI is an ideal index to estimate preoperative traction force. LCEA affected traction force, whilst AA and Beighton score did not. Measuring the muscle volume can help estimate the most suitable traction force for the patient. IV.

Sex-Based Differences in Outcomes After Hip Arthroscopic Surgery for Femoroacetabular Impingement: A Systematic Review.

While sex-based differences in outcomes after hip arthroscopic surgery for femoroacetabular impingement syndrome (FAIS) are often recorded, no studies have been dedicated to analyzing the literature as a whole. To investigate whether sex is a predictor of outcomes in studies evaluating hip arthroscopic surgery for FAIS. Systematic review; Level of evidence, 4. A systematic review was conducted following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. We searched the PubMed, Embase, Cochrane, Ovid, and PubMed Central databases for English-language studies that evaluated sex-specific outcomes in human populations. The search terms used were as follows: ("Hip Arthroscopy") AND ("Femoroacetabular Impingement" OR "FAI") AND ("Sex" OR "Gender" OR "Male" OR "Female"). Studies with evidence levels 2 through 4 were included. The studies were then screened, followed by data extraction. Modified Harris Hip Score (mHHS) outcomes and return-to-sport (RTS) rates were recorded. These were analyzed using random-effects meta-analysis. Heterogeneity was calculated using the I 2 statistic. Of 256 full-text articles screened, 48 articles were included in this analysis; of these, 14 studies (29%) concluded that female sex was a negative predictor of postoperative outcomes, while 6 studies (13%) found female sex to be positive predictor. The remaining 28 studies (58%) found no sex-based differences in postoperative outcomes. Of 7 studies (416 male and 519 female) included in the mHHS analysis, 2 studies concluded that male patients had significantly higher postoperative mHHS scores. Of 6 studies (502 male and 396 female) included in the RTS analysis, 1 study concluded that male patients had a significantly higher RTS rate. Almost one-third of the included studies determined that female sex was a negative predictor of postoperative outcomes, 13% found female sex to be a positive predictor, and 58% found no sex-based differences. Our study illustrates an insufficiency of high-level evidence supporting sex-specific differences in outcomes after hip arthroscopic surgery, but findings indicated that the postoperative mHHS score and RTS rate may be influenced by sex.

Translated article] Past and projected temporal trends in arthroscopic hip surgery in Spain between 1998 and 2018

ObjectiveDescribe the population incidence of hip arthroscopy from 1998 to 2018 and to project the trends for the year 2030, as well as to describe the variations in the population incidence between the autonomous communities. Material and methodA retrospective review of the minimum basic data set from 1998 to 2018 was carried out. Temporal evolution was analysed and the variables associated with the indication (age, sex, regions) were identified. For each region, the crude rate per 100,000 inhabitants was calculated. The 2019–2030 projection was made using linear regression. ResultsIn Spain between 1998 and 2018 a total of 10,663 arthroscopic hip surgeries were carried out. The population incidence in 1998 was 0.14 CAC per 100,000 inhabitants, while in 2018 it was 4.09. For the year 2030 an increase of 156.9% in the number of arthroscopic hip surgeries is expected (p<.001). On average, 57.7% of all procedures (95% CI 55.2–60.2) were done in men and the highest incidence was found in ages≤44 years. The geographical variation was 81%, being up to 15.4 times the difference in incidence per 100,000 inhabitants between some regions. ConclusionsThe number of hip arthroscopies in Spain has been increasing in the 1998–2018 period and this growing trend is expected to continue until 2030. In Spain, hip arthroscopic procedures are performed more frequently in male patients and in under 45 years old. The variability of the population incidence between the autonomous communities is high.

Use of Anatomic Radiographic Horizons for the Lateral Center-Edge Angle in the Classification of Hip Dysplasia

Background: The lateral center-edge angle of Wiberg (LCEA) and Tönnis angle (TA) rely on a “horizon” that functions as a reference point for measurements of hip dysplasia on weightbearing anteroposterior pelvis radiographs. There are 3 different horizons that are currently utilized depending on surgeon preference: (1) a line parallel to the radiographic floor (F), (2) a line that connects the inferior portions of the acetabular teardrops (ATs), or (3) a line that connects the ischial tuberosities (ITs). It is imperative to accurately assess the degree of hip dysplasia on initial workup to select the appropriate surgical intervention. Purpose: To assess how the choice of a radiographic horizon affects the measurements of the LCEA and TA. The secondary purpose was to assess how the horizon affected the classification of hips as either normal, borderline dysplastic, or dysplastic. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: The LCEA and TA were measured on all preoperative weightbearing anteroposterior pelvis radiographs for 186 consecutive patients who underwent hip preservation surgery between February 2016 and November 2020 (140 hip arthroscopic procedures, 46 combined hip arthroscopic procedures with periacetabular osteotomy), 3 times per hip, each time using an F, AT, and IT horizon. The Student t test was used to analyze the differences in the measurements of the LCEA and TA, and discordance rates in the dysplasia classification between horizons were quantified. Results: For the entire study population, the mean LCEAF (23.4°± 7.4°) was significantly greater than the mean LCEAIT (23.1°± 7.2°) (95% CI, −0.634 to −0.003; P = .047) and mean LCEAAT (23.0°± 7.1°) (95% CI, −0.723 to −0.139; P = .004). There was no difference between the LCEAIT and LCEAAT (95% CI, −0.305 to 0.080; P = .251). When stratified by hip arthroscopic surgery, the mean LCEAF (26.3°± 5.6°) was significantly greater than the mean LCEAAT (25.8°± 5.3°) (95% CI, −0.845 to −0.162; P = .004). Overall, there was a 17.7% and 18.3% discordance rate in the dysplasia classification using the LCEAIT and LCEAAT compared with the LCEAF, respectively. There were no statistically significant differences between the mean TAIT, TAAT, and TAF for the entire study population, the arthroscopic surgery group, and the combined arthroscopic surgery and periacetabular osteotomy group. Conclusion: There was no statistical difference between the AT and IT horizons for LCEA measurements. The dysplasia classification was in better agreement between the 2 anatomic horizons compared with the F horizon. The TA was not affected by changes in the horizon.

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

Background: Few studies have compared outcomes, return to sport (RTS), and continuation of sport (CTS) after primary hip arthroscopic surgery between matched groups of male and female athletes with a minimum 5-year follow-up. Purpose: (1) To report minimum 5-year patient-reported outcome (PRO) scores as well as RTS and CTS rates for elite female athletes undergoing hip arthroscopic surgery for femoroacetabular impingement syndrome (FAIS) and (2) to compare clinical results with those of a matched control group of elite male athletes. Study Design: Cohort study; Level of evidence, 3. Methods: Data were prospectively collected and retrospectively reviewed for elite (collegiate or professional) female athletes who underwent primary hip arthroscopic surgery for FAIS between March 2009 and March 2016. Inclusion criteria were preoperative and minimum 5-year scores for the modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score–Sport Specific Subscale, and visual analog scale for pain. Exclusion criteria were Tönnis grade >1, hip dysplasia, previous ipsilateral hip surgery/conditions, and those unwilling to participate. Rates of achieving the minimal clinically important difference (MCID), Patient Acceptable Symptom State (PASS), and maximum outcome improvement satisfaction threshold (MOIST) were recorded in addition to RTS. CTS was also recorded and defined as athletes reporting continued sport activity at a minimum 5-year follow-up after initially reporting returning to sport. Elite female athletes were propensity matched in a 1:1 ratio to elite male athletes for comparison. Results: A total of 81 hips in elite female athletes that underwent primary hip arthroscopic surgery met the inclusion criteria, and follow-up was available for 65 hips (80.2%) at a mean of 67.6 ± 6.5 months, with a mean age of 24.3 ± 6.8 years. Female athletes demonstrated significant improvements in all recorded PRO scores; achieved the MCID, PASS, and MOIST at high rates; returned to sport at a rate of 80.4%; and continued sport at a rate of 97.1%. Female athletes demonstrated lower preoperative PRO scores compared with male athletes, but postoperative PRO scores; improvements in scores; rates of achieving the MCID, PASS, MOIST; and RTS and CTS rates were similar between female and male athletes. Conclusion: Elite female athletes undergoing primary hip arthroscopic surgery for FAIS demonstrated favorable PRO scores and high RTS and CTS rates at a minimum 5-year follow-up. These results were comparable with those of a propensity-matched control group of elite male athletes.

Effect of Anchor Density on Functional Outcomes After Arthroscopic Hip Labral Repair

Background: While labral repair has been widely adopted as the first line treatment for labral injury during hip arthroscopy, there is no widespread consensus on the procedural technique, including the number of anchors that should be used to avoid recurrent instability and revision surgery. Purpose: To determine if anchor density can predict patient-reported outcomes after arthroscopic labral repair in the hip. Study Design: Cohort study; Level of evidence, 3. Methods: Patients aged 18 to 50 years who underwent primary hip arthroscopic surgery with labral repair between January 2011 and December 2016 were identified from a prospectively collected database. Exclusion criteria consisted of previous ipsilateral surgery, osteoarthritis (Tönnis grade >1), and severe cartilage defects (Outerbridge grade III/IV) or concomitant labral reconstruction, capsular reconstruction, or microfracture. Minimum 2-year patient-reported outcomes (modified Harris Hip Score [mHHS], Hip Outcome Score [HOS]–Activities of Daily Living [ADL], HOS–Sport Specific Subscale [SSS], 12-Item Short Form Health Survey [SF-12]), rates of achieving the minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) for each score, revision surgery rate, and rate of conversion to total hip arthroplasty (THA) were compared based on anchor density (number of anchors per millimeter of labral tear). Results: A total of 634 hips (575 patients) with a mean age of 30.4 ± 9.5 years (range, 18.0-49.9 years) met inclusion criteria. The mean labral tear size was 31 ± 11 mm (range, 2-70 mm) with a median number of anchors used for labral repair of 3 (range, 1-7) and mean anchor density of 0.11 ± 0.08 anchors (range, 0.03-1.33) per millimeter of labral tear. Hips with a minimum 2-year follow-up (451/634 [71.1%]) had significant improvements on the mHHS, HOS-ADL, HOS-SSS, and SF-12 Physical Component Summary (P < .001 for all). There was no significant correlation detected between anchor density or number of anchors used and postoperative scores (correlation coefficient range, –0.05 to 0.17; P > .05 for all). The rate of revision surgery was 6.4% (28 patients), with 8 hips found to have labral tears and/or deficiency on revision. Additionally, 6 hips (1.3%) had to undergo THA at a mean of 3.6 ± 2.1 years (range, 2.0-5.5 years). Conclusion: Anchor density did not have a correlation with postoperative outcomes, achieving the MCID or PASS, revision hip arthroscopic surgery, complications, or conversion to THA.

Hip Impingement Location in Maximal Hip Flexion in Patients With Femoroacetabular Impingement With and Without Femoral Retroversion

Background: Symptomatic patients with femoroacetabular impingement (FAI) have limitations in daily activities and sports and report the exacerbation of hip pain in deep flexion. Yet, the exact impingement location in deep flexion and the effect of femoral version (FV) are unclear. Purpose: To investigate the acetabular and femoral locations of intra- or extra-articular hip impingement in flexion in patients with FAI with and without femoral retroversion. Study Design: Cross-sectional study; Level of evidence, 3. Methods: An institutional review board–approved retrospective study involving 84 hips (68 participants) was performed. Of these, symptomatic patients (37 hips) with anterior FAI and femoral retroversion (FV <5°) were compared with symptomatic patients (21 hips) with anterior FAI (normal FV) and with a control group (26 asymptomatic hips without FAI and normal FV). All patients were symptomatic, had anterior hip pain, and had positive anterior impingement test findings. Most of the patients had hip/groin pain in maximal flexion or deep flexion or during sports. All 84 hips underwent pelvic computed tomography (CT) to measure FV as well as validated dynamic impingement simulation with patient-specific CT-based 3-dimensional models using the equidistant method. Results: In maximal hip flexion, femoral impingement was located anterior-inferior at 4 o’clock (57%) and 5 o’clock (32%) in patients with femoral retroversion and mostly at 5 o’clock in patients without femoral retroversion (69%) and in asymptomatic controls (76%). Acetabular intra-articular impingement was located anterior-superior (2 o’clock) in all 3 groups. In 125° of flexion, patients with femoral retroversion had a significantly (P < .001) higher prevalence of anterior extra-articular subspine impingement (54%) and anterior intra-articular impingement (89%) compared with the control group (29% and 62%, respectively). Conclusion: Knowing the exact location of hip impingement in deep flexion has implications for surgical treatment, sports, and physical therapy and confirms previous recommendations: Deep flexion (eg, during squats/lunges) should be avoided in patients with FAI and even more in patients with femoral retroversion. Patients with femoral retroversion may benefit and have less pain when avoiding deep flexion. For these patients, the femoral location of the impingement conflict in flexion was different (anterior-inferior) and distal to the cam deformity compared with the location during the anterior impingement test (anterior-superior). This could be important for preoperative planning and bone resection (cam resection or acetabular rim trimming) during hip arthroscopy or open hip preservation surgery to ensure that the region of impingement is appropriately identified before treatment.

The analgesic benefit of Pericapsular Nerve Group (PENG) block in hip arthroscopic surgery: a retrospective pragmatic analysis at an academic health center

IntroductionThe novel pericapsular nerve group (PENG) block has recently been reported to provide effective motor-sparing local anesthetic-based analgesia to the hip joint. We aimed to evaluate the analgesic efficacy and...

Pericapsular nerve group (PENG) block for hip arthroscopy: a randomized, double-blinded, placebo-controlled trial

IntroductionArthroscopic hip surgery is associated with significant postoperative pain. Femoral nerve blocks have been shown to improve postoperative analgesia at the expense of quadriceps weakness. The pericapsular nerve group (PENG)...

Outcomes of Staged Bilateral Hip Arthroscopic Surgery in the Context of Femoroacetabular Impingement Syndrome: A Nested Matched-Pair Control Study Focusing on the Effect of Time Between Procedures

Background: Bilateral hip symptoms from femoroacetabular impingement syndrome (FAIS) are a common finding in patients regardless of athletic involvement. Oftentimes, patients and surgeons choose to stage bilateral hip arthroscopic surgery. Purpose/Hypothesis: The purpose of this study was (1) to compare minimum 2-year outcomes between patients who underwent staged bilateral hip arthroscopic surgery for FAIS to a propensity score–matched control group that underwent unilateral hip arthroscopic surgery and (2) to investigate the effect of time between bilateral procedures on patient-reported outcomes (PROs). We hypothesized that, after bilateral hip arthroscopic surgery, the improvement in outcomes would be similar to that after unilateral hip arthroscopic surgery and the time duration between bilateral procedures would not affect the final outcome. Study Design: Cohort study; Level of evidence, 3. Methods: Data were retrospectively reviewed on a consecutive series of patients who underwent primary hip arthroscopic surgery at our institution between June 2008 and November 2017. Patients who underwent bilateral hip arthroscopic surgery with minimum 2-year PROs for the modified Harris Hip Score (mHHS), the Nonarthritic Hip Score (NAHS), the Hip Outcome Score–Sports Specific Subscale (HOS-SSS), patient satisfaction, and a visual analog scale (VAS) for pain were included. The study group was matched 1:1 based on age, sex, and body mass index to a control group that only required unilateral hip arthroscopic surgery. Additionally, a subanalysis was performed on the study group to determine the effect of time between arthroscopic procedures. Rates of achieving the minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) for the mHHS and HOS-SSS were determined. The P value was set at <.05. Results: A total of 205 patients (410 hips) were included. The mean age and body mass index of the study group were 32.3 ± 13.2 years and 25.0 ± 5.1, respectively. All 410 hips that met the inclusion criteria were matched. There were no significant differences in patient, radiographic, or procedural data. A significant and comparable improvement was reported for all PRO measures and the VAS (P < .0001) in both groups. Similarly, rates of achieving the MCID and PASS were comparable. After dividing the study group based on whether the contralateral procedure was performed <3 months or >3 months after the first procedure, it was determined that patients had a significant improvement and favorable outcomes regardless of time between bilateral procedures. Conclusion: Patients who underwent unilateral and bilateral hip arthroscopic surgery for FAIS had a significant and comparable improvement in PROs at a minimum 2-year follow-up. A time interval of <3 months or >3 months between bilateral procedures did not affect PROs.

Poster 193: Increased Hip Distractability in the Revision Hip Arthroscopy Setting: A Comparison Between Revision and Native Contralateral Hips with an Intra-Operative Axial Stress Exam Under Anesthesia

Objectives:Hip instability secondary to capsular insufficiency is a cause of persistent pain and/or functional disability following primary hip arthroscopy in a poorly defined subset of patients. Further, an easily distractible hip exam under anesthesia is a finding that has been described in the diagnosis of hip instability; however, the exam has relied on subjective findings of a perceived looseness and has lacked objective criteria. The purpose of this study was to compare intraoperative hip joint distractibility between hips that previously underwent arthroscopic surgery and the contralateral hip with no history of surgical manipulation.Methods:Patients undergoing revision hip arthroscopy between April 2019 and December 2020, who previously underwent arthroscopic hip surgery for femoroacetabular impingement syndrome, were prospectively enrolled. Exclusion criteria was any contralateral hip surgery. Prior to instrumentation, fluoroscopic images of both hips were obtained at 25 lb traction intervals up to 100 lbs. Total joint space and distraction were measured at each traction interval. (Figure 1) Distraction was calculated as the difference between the baseline joint space and the total joint space at each subsequent traction interval. (Figure 2) Wilcoxon signed ranks tests and McNemar tests were used to compare distraction between revision and native contralateral hips.Results:Forty-seven patients were included. Mean distraction of operative hips was significantly greater than mean distraction of non-operative hips at traction intervals of 50 lbs (2.13 vs. 1.04 mm, p = 0.002), 75 lbs (6.39 vs. 3.70 mm, p < 0.001), and 100 lbs (8.24 vs. 5.39, p < 0.001) (Figure 3). Mean total joint space of operative hips was significantly greater than mean total joint space of non-operative hips at traction intervals of 50 lbs (6.60 vs. 5.39 mm, p < 0.001), 75 lbs (10.86 vs. 8.05 mm, p < 0.001), and 100 lbs (12.73 vs. 9.73, p < 0.001). A higher percentage of operative hips achieved all distraction thresholds, in 2-mm intervals up to 10-mm, at each traction interval (Table 1).Conclusions:In the majority of patients undergoing revision hip arthroscopy, previous arthroscopic hip surgery increases axial distractibility of the hip joint compared to the native contralateral hip at axial traction forces of 50-100 lbs. Increased axial distractibility following hip arthroscopy may be suggestive of hip instability, and can be assessed on a stress exam under anesthesia.Table 1. Total and percentage of hips achieving millimetric distraction thresholds in 2mm intervals up to 10mm in operative and native hips.

Poster 192: Femoroacetabular Impingement in Elite Skiers and Snowboarders: Return to Sport and Outcomes after Hip Arthroscopy

Objectives:Hip arthroscopy has been shown to be an effective treatment for femoroacetabular impingement (FAI) in high level athletes; however, limited outcomes and return to play data exists for hip arthroscopy in skiers and snowboarders. The purpose of this study is to determine the return to sport rate of elite skiers and snowboarders who have undergone hip arthroscopic surgery for FAI and to assess hip-related outcomes at a minimum 2-years follow up.Methods:Elite skiers and snowboarders who underwent hip arthroscopy for the treatment of FAI between 2005 and 2018 were identified through a retrospective review of prospectively collected data. Data was obtained from www.fis-ski.org, www.usskiandsnowboard.org, www.xgames.com, and www.wikipedia.org, including information on each players’ career length, participation on a national team, and time between surgery and first competition post-surgery. Patient reported outcome measures (PROs) were prospectively collected pre-operatively and at minimum 2 years post-operatively.Results:Twenty-six elite skiers and snowboarders (34 hips) were included. The mean age at surgery was 24.5 ± 6.7 years (range 18.7-46.8). A total of 85% returned to elite level competition at 8.9 months (range 2.9-23.7) with an average career length of 3.6 ± 2.7 years. Four athletes required revision arthroscopy with adhesions being the most frequent indication. At mean follow-up of 7.7 ± 3.2 years, significant improvement in PROs was demonstrated for HOS-ADL (76 ± 20 to 95 ±6), HOS-SSS (63 ± 28 to 92 ± 14), mHHS (70 ± 19 to 89 ± 12), and SF12-PCS (45 ± 11 to 54 ± 8). Patient acceptable symptom state (PASS) was achieved in 88% for HOS-ADL, 88% for HOS-SSS, and 83% for mHHS. Median patient satisfaction was 10.Conclusions:The return to competition rate in elite skiers and snowboarders after hip arthroscopy for FAI is 85% at an average of 8.9 months with a career length of 3.6 years after surgery. Significant improvement in PROs was demonstrated for HOS-ADL, HOS-SSS, mHHS, and SF12-PCS with median patient satisfaction score of 10. These findings support hip arthroscopy as an effective procedure for the treatment of FAI in elite skiers and snowboards with symptomatic activity limiting hip pain allowing them to return to their previously level of competition at a high rate.