Editorial Commentary: Incremental Decompression of Cam Femoroacetabular Impingement Must Be Assessed in Real Time by Arthroscopic Dynamic Examination: Playbook for the Perfect Femoroplasty.

The perfect femoroplasty varies with the individual patient's pathoanatomy and is a prime example of the art and science of surgery. Radiographs are two-dimensional representations of a three-dimensional reality and can miss detection of cam impingement. Cam impingement may occur without cam morphology as femoral retrotorsion and/or supraphysiological range of motion (e.g., dancers and martial artists) may cause cam impingement with normal α-angles and anterior offset. Acetabuloplasty or acetabular reorientation osteotomy may change the dynamic interaction between the proximal femur and acetabular rim and may alter the location and extent of cam decompression. Although much is discussed about the α-angle, restoration of anterior offset is also important. Incremental femoroplasty assessed in real time by arthroscopic dynamic examination is key, as the surgeon sculpts a nonimpinging proximal femur using a burr rather than a chisel in creating a customized surgical masterpiece.

Labral Degeneration Predicts Inferior Mid-Term Outcomes in Hip Labral Repair: A Multicenter Comparative Analysis.

PURPOSE: To analyze and compare the mid-term outcomes of hip arthroscopy for patients with and without labral degeneration from multiple orthopaedic centers. The purpose of this research is to develop an understanding of the impacts of labral degeneration on patient outcomes following arthroscopic treatment of labral tears. METHODS: A prospective multicenter hip arthroscopy registry was queried for primary surgeries from January 2014 to October 2017 with completed 2-year International Hip Outcome Tool-12 (iHOT-12) reports. Patients were placed into cohorts based on the presence or absence of labral degeneration noted intraoperatively during hip arthroscopy. Degeneration was defined as yellowing, ossification, or calcification present in at least 50% of the labrum. Differences in baseline variation between groups were assessed with a Wilcoxon rank-sum test or χ2 test. Two-year outcomes were assessed with iHOT-12. Multivariate logistic regression models were fitted while controlling for age, body mass index, sex, and preoperative iHOT-12 scores to identify significant predictors of achieving the clinically significant thresholds of minimal clinically important difference, substantial clinical benefit, and patient-acceptable symptom scale. RESULTS: In total, 735 patients met inclusion criteria, of whom 613 had complete outcomes information. Relative to the control group, the labral degeneration group was significantly older (mean age 44 ± 11 years vs 33 ± 12 years; P < .01). Both groups experienced statistically significant improvement in iHOT-12 scores from baseline to final follow-up (P < .001); however, patients with labral degeneration reported inferior 2-year iHOT-12 scores when compared with patients without degeneration (P < .001). In the logistic regression models, labral degeneration was a significant negative predictor of achieving iHOT-12 minimal clinically important difference (odds ratio [OR] 0.47; 95% confidence interval [95% CI] 0.28-0.79), patient acceptable symptom state (OR 0.50; 95 CI 0.32-0.77), and substantial clinical benefit (OR 0.58; 95% CI 0.37-0.89). CONCLUSIONS: The results of our study conclude that patients with nondegenerative labral tissue at the time of repair have superior patient-reported outcomes at mid-term follow-up. The presence of labral degeneration was a negative predictor of achieving clinically significant thresholds after controlling for patient age, body mass index, sex, and baseline iHOT-12 scores. LEVEL OF EVIDENCE: III, retrospective comparative prognostic trial.

Acetabular Cartilage Lesions Predict Inferior Mid-Term Outcomes for Arthroscopic Labral Repair and Treatment of Femoroacetabular Impingement Syndrome.

PURPOSE: To analyze the effect of acetabular chondrosis at a minimum of 2 years following hip arthroscopy in patients undergoing labral repair and treatment of femoroacetabular impingement. METHODS: From 2014 to 2017, patients undergoing arthroscopic labral repair were prospectively enrolled in a multicenter hip arthroscopy registry. The registry was retrospectively queried for primary labral repair patients with complete 2-year outcomes and a Tonnis grade of less than 2. Patients were grouped according to severity of articular cartilage damage noted intraoperatively using the Beck classification system: none, low-grade (Grade 1 or 2), or high-grade (Grade 3 or 4) damage. A Kruskal-Wallis test and post hoc Dunn's test with Holm correction compared 2-year postoperative outcome scores of the iHOT-12 scale between groups. The proportion of patients in each cohort who achieved the clinically significant thresholds of the minimum clinically important difference (MCID), patient-acceptable symptom scale, and substantial clinical benefit (SCB) were analyzed. Multivariate logistic regression models identified predictors of achieving clinical thresholds while controlling for demographic variation. RESULTS: 422 patients met inclusion criteria, from which 347 completed 2-year outcomes. All groups experienced improvement in iHOT-12 scores from baseline to follow-up (P < .001). iHOT-12 scores at follow-up were inferior for Low-Grade Damage and High-Grade Damage Groups relative to the No Damage Group (P = .04; P = .03). When accounting for age, body mass index, gender, and preoperative iHOT-12 scores in logistic regression models, the presence of high-grade lesions was a negative predictor for achieving SCB (OR [95% CI], 0.54 [0.29-0.96]) and low-grade lesions a negative predictor for achieving MCID (0.50 [0.27-0.92]. Among patients with high-grade lesions, there was no significant difference in 2-year iHOT-12 scores between those undergoing chondroplasty (n = 50) and those undergoing microfracture (n = 14) (P = .14). CONCLUSIONS: Acetabular cartilage damage portends inferior patient-reported outcomes 2 years after primary labral repair and treatment of femoroacetabular impingement. The presence of cartilage lesions was a negative predictor of individual achievement of several clinical thresholds. LEVEL OF EVIDENCE: III, Retrospective comparative cohort.

Multicenter Outcomes After Primary Hip Arthroscopy: A Comparative Analysis of Two-Year Outcomes After Labral Repair, Segmental Labral Reconstruction, or Circumferential Labral Reconstruction.

PURPOSE: (1) To report minimum 2-year follow-up patient-reported outcome measures in patients undergoing labral repair (LR), segmental labral reconstruction (SLR), or circumferential labral reconstruction (CLR) in the primary setting; and (2) to compare minimum 2-year follow-up patient-reported outcome measures among these groups. METHODS: A retrospective review of a prospectively maintained multicenter database of patients undergoing hip arthroscopy was performed. Inclusion criteria were patients undergoing hip arthroscopy for treatment of labral tear and femoroacetabular impingement syndrome between January 2014 and October 2017, and completion of minimum 2-year postoperative outcome scores. Exclusion criteria were patients undergoing revision hip surgery, labral treatment limited to debridement, lateral center-edge angle <20°, osteoarthritis (Tönnis grade > 1), slipped capital femoral epiphysis, workers compensation status, and patients undergoing concomitant gluteus medius and/or minimus repair. Labral reconstruction patients were matched (1:3) with labral repair patients on age, sex, and body mass index. The labral reconstruction group was further stratified into SLR, and CLR groups. Patient demographic characteristics and clinical outcomes including Hip Outcome Score - Activities of Daily Living, Hip Outcome Score - Sport Subscale, modified Harris Hip Score, international Hip Outcome Tool, and visual analog scale for pain were analyzed, as well as achievement of the minimal clinical improvement difference (MCID). A P-value less than .05 indicated statistical significance. RESULTS: A total of 416 patients were included (LR, n = 312; SLR, n = 53; CLR, n = 51). The age, body mass index, and sex of the matched cohort were 42.3 ± 11.2 years, 24.7 ± 3.7, and 55.0% female. At a minimum of 2-year after hip arthroscopic surgery, no differences were found in preoperative, postoperative, or the delta visual analog scale for pain, modified Harris Hip Score, Hip Outcome Score - Activities of Daily Living, Hip Outcome Score - Sport Subscale, or international Hip Outcome Tool. Subsequently, the proportion of patients achieving the MCID and the PASS at latest follow-up were analyzed. This analysis revealed that no significant differences in the rate of MCID or PASS achievement for any outcome measure existed based on labral treatment. CONCLUSIONS: In this multicenter study on labral treatment in the primary setting, patients undergoing LR, SLR, and CLR demonstrated no difference in preoperative or postoperative scores, nor the proportion of patients achieving clinically significant outcome improvement. LEVEL OF EVIDENCE: III; therapeutic outcome study with controls.

Symptom duration predicts inferior mid-term outcomes following hip arthroscopy.

INTRODUCTION: Studies have demonstrated a negative relationship between the length of time with symptoms and patient-reported outcome measures in primary hip arthroscopy. Our aim was to expand the generalizability of this finding with a multi-center cohort. METHODS: A multi-center hip arthroscopy registry was queried for patients undergoing primary hip arthroscopy from 2014 to 2017. Patients were stratified according to whether pre-operative symptom duration exceeded two years or did not exceed two years. A Wilcoxon rank sum test was performed for differences in two year post-operative outcome scores. Logistic regression models analyzed the influence of symptom duration on achieving clinically meaningful thresholds (minimum clinically important difference, patient-acceptable symptom state, substantial clinical benefit) when controlling for baseline scores, age, BMI, and sex. RESULTS: Seven hundred forty-four patients met the inclusion criteria, from which 620 had complete outcomes information. The mean ± SD 2-year iHOT-12 scores of patients with symptom duration greater than two years (69 ± 26) were significantly lower than patients with symptom duration less than two years (77 ± 23) (Dunn test, p < 0.001). Chronic duration of pain was a negative predictor of achieving iHOT-12 MCID (0.47 [0.31-0.72]), PASS (0.53 [0.37-0.76]), and SCB (0.67 [0.47-0.94]). CONCLUSION: When controlling for differences in baseline demographic factors and pre-operative iHOT-12 scores, patients with chronic pain report poorer functional outcomes at mid-term follow-up. These results suggest that chronic pain predicts inferior outcomes from primary hip arthroscopy and that surgical intervention at earlier time points may be beneficial in achieving better outcomes.

Editorial Commentary: Expansion of Hip Arthroscopy in Sports Medicine Fellowship Training: The Good, Bad, and Ugly.

Orthopaedic sports medicine fellowship experience in hip arthroscopy is increasing rapidly (2.6-fold from 2011 to 2016), although the case numbers vary quite widely (64-fold) depending on the program. Orthopaedic providers are now able to refine diagnoses and refer or render indicated less-invasive hip treatment options, many of which yield outcomes equaling or surpassing those of open equivalents. Patients benefit. Our profession benefits. However, advanced hip arthroscopy procedures are technically challenging, and complications can be significant in inexperienced hands. For those who choose to perform hip arthroscopy after fellowship training, continuing hip arthroscopy education and skill development is essential.

Editorial Commentary: Managing Hip Pain, Athletic Pubalgia, Sports Hernia, Core Muscle Injury, and Inguinal Disruption Requires Diagnostic and Therapeutic Expertise.

Pubalgia means pubic pain. This is different from core muscle injury (implying muscular pathology) or inguinal disruption (different anatomic region). Athletic pubalgia includes a myriad of pathologic conditions involving the pubic symphysis, adductors, rectus abdominis, posterior inguinal wall, and/or related nerves. Moreover, growing evidence supports a link between femoroacetabular impingement (FAI) and pubalgic conditions. Constrained hip range of motion in flexion causing obligatory transitory, even ballistic, posterior tilting of the hemipelvis may produce pathologic transfer stress to not only the pubic symphysis but the sacroiliac joint, lumbar spine, and proximal hamstrings, manifesting in diverse, often-painful, conditions. In select cases of pubalgia, patients may have clinical improvement with concurrent or even isolated treatment addressing FAI. Unlike atypical posterior hip pain from FAI, which may be referred pain that might respond favorably, albeit temporarily, to an intra-articular injection, secondary pubic pain from a transfer stress pathomechanism might not be expected to benefit from such. And, it's not always FAI. Some patients who do not respond to nonoperative management may not require arthroscopic surgery and might benefit from open or laparoscopic mesh hernia repair, adductor tenotomy, primary tissue (hernia) repair, rectus abdominis repair, or even endoscopic surgery for osteitis pubis and/or pubalgia. And, finally, these may be combined with FAI surgical treatment. Refinement of definitions, pathologic conditions, technical advances, and collaboration with general surgeons will best help us treat our patients.

Arthroscopic classification of intra-articular hip pathology demonstrates at best moderate interrater reliability.

PURPOSE: The purpose of this study was to report several novel classification systems for intra-articular lesions observed during hip arthroscopy, and to quantify the interrater reliability of both these novel systems and existing classifications of intra-articular lesions when tested by a group of high-volume hip arthroscopists. METHODS: Five hip arthroscopists deliberated over shortcomings in current classification systems and developed several novel grading systems with particular effort made to capture factors important to the treatment and outcomes of hip arthroscopy for labral injury. A video learning module describing the classifications was then developed from the video archive of surgeries performed by the senior author and reviewed by study participants. Following review of the module, a pilot study was completed using five randomly selected videos, after which participating surgeons met once more to discuss points of disagreement and to seek clarification. The final video collection for testing reliability was composed of 29 videos selected with the intent of capturing all sublevels of each classification scheme. Study participants recorded their assessments using each classification scheme, and interrater reliability was calculated by a study participant not involved in grading. RESULTS: The average kappa coefficients for the classification schemes ranged from 0.38 to 0.54, with the interrater reliability of all classification schemes except labral degeneration qualifying as moderate. The percent of cases with absolute agreement ranged from 17.2% to 51.7% across the classification systems. CONCLUSIONS: Even among a group of high-volume hip arthroscopists who engaged in several discussions about the proposed classification schemes, grades were found to have at best moderate interrater reliability. Moderate interrater reliability is demonstrated for novel grading systems for describing labral tear complexity, labral bruising, labral size, and extent of synovitis, and fair reliability is demonstrated for labral degeneration. Further development and refinement of multifactorial grading systems for describing labral injury are indicated. Evaluating the multifactorial nature of intra-articular lesions in the hip is an important part of intraoperative decision-making and defining reliable classifications for intra-articular lesions is a critical first step towards developing generalizable criteria for guiding treatment type. LEVEL OF EVIDENCE: Level III.

Anterior dislocation of THA after Iliopsoas tenotomy in spinopelvic imbalance: a rare case report.

BACKGROUND: Iliopsoas impingement is a complication of total hip arthroplasty that often manifests as groin pain during initial hip flexion. However, there are no reports of mechanical complications after iliopsoas tenotomy following total hip arthroplasty (THA). CASE PRESENTATION: We present the case of a 64-year-old woman with degenerative lumbar kyphosis who developed anterior hip dislocations after arthroscopic iliopsoas tenotomy for anterior impingement following THA. She ultimately required revision of the acetabular cup. CONCLUSIONS: Arthroscopic tenotomy for refractory iliopsoas tendinopathy may be appealing because of its less invasive nature. However, caution should be exercised in the setting of significant cup malpositioning and/or spinopelvic imbalance to avoid iatrogenic anterior instability.

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

PURPOSE: The purposes of this study were to (1) evaluate the effect of age on clinical outcomes of arthroscopic femoroacetabular impingement (FAI) with labral preservation surgery and (2) identify predictors of poor postoperative clinical outcomes. METHODS: Eighty-four patients who underwent hip arthroscopic treatment for FAI between 2009 and 2013 were retrospectively reviewed. Patients were divided into three groups based on age. The Advanced age group consisted of patients over 70 years old, the Middle age group consisted of patients in their 50s and 60s, and the Younger age group consisted of patients less than 50 years of age. Total hip arthroplasty (THA) conversion, radiographic progression of osteoarthritis and patient-reported outcomes including modified Harris Hip Score (MHHS) and Non-arthritic Hip Score (NAHS) were investigated. RESULTS: The mean follow-up period was 32.2 (range 24-60) months. THA was required in 3 patients in their 50s and 60s, which was a significantly higher rate compared to that in patients Younger than 50 years old (17% vs 0%, p = 0.036). Progression to osteoarthritis was also significantly more frequent in patients in their 50s and 60s than in patients in their 70s (50s and 60s: 33%; 70s: 0%, p = 0.030). In all age groups, the preoperative MHHS and NAHS improved at last follow-up (p < 0.001). The 50s and 60s age group [hazard ratio (HR) 6.62], preoperative mild osteoarthritic change (Tönnis grade 1, HR: 3.29) and severe cartilage damage on the acetabulum (HR: 2.63) were risk factors for progressive osteoarthritis and THA conversion. CONCLUSIONS: Arthroscopic FAI correction and labral preservation surgery provide favourable clinical outcomes for patients over 70 years old in the absence of significant osteoarthritis and severe acetabular chondral damage. Patients in their 50s and 60s have a higher risk of both THA conversion and progressive osteoarthritis, while patients aged over 70 years show no evidence of progressive osteoarthritis. Chronologic age in isolation is not an absolute contra-indication to hip arthroscopy. LEVEL OF EVIDENCE: III.

Editorial Commentary: Hip Arthroscopy-Bimodal Bump and Volume Matters.

In the experience of a high-volume hip arthroscopic surgeon with a referral practice, a bimodal age distribution could be common. Younger patients presenting with symptomatic hip pathology recalcitrant to nonoperative management may seek or be referred to high-volume surgeons, and older patients absent significant osteoarthritis may also be surgical candidates. Lower-volume hip surgeons could have higher complication rates, and it is incumbent on higher-volume surgeons to train upcoming colleagues as hip arthroscopy continues to grow.

Editorial Commentary: When Enough Is Enough-Orthopaedic Procedures With Long Learning Curves and the Case of Hip Arthroscopy.

The incidence of hip arthroscopy is increasing over time, as is the rate of labral repairs performed by American Board of Orthopaedic Surgery candidates in general and by sports medicine fellowship-trained candidates in particular. However, both arthroscopic labral debridement and repair yield excellent minimum 10-year outcomes in well-selected femoroacetabular impingement patients. In my practice, most hip arthroscopy patients undergo labral repair, and labral reconstruction is performed in about 4%, so I view the rising use of labral repair as a step forward. But concerns remain. How many of these American Board of Orthopaedic Surgery candidates will be able to hone their arthroscopic skills (and clinical judgment) in anywhere near the number of cases needed to achieve demonstrably low reoperation rates? In addition, will these fledgling surgeons be able to perform labral reconstructions or augmentations when indicated, bearing in mind that only half of such cases could be predicted preoperatively? The definition of adequate hip arthroscopy training remains up for grabs.

Arthroscopic Outcomes as a Function of Acetabular Coverage From a Large Hip Arthroscopy Study Group.

PURPOSE: To report comparative hip arthroscopic outcomes of patients with low (borderline dysplasia), normal, and high (global pincer femoroacetabular impingement [FAI]) lateral acetabular coverage. METHODS: A retrospective analysis of prospectively collected data from a multicenter registry was performed. Primary hip arthroscopy patients were assigned to 1 of 3 groups based on preoperative lateral center-edge angle: borderline dysplasia (≤25°), normal (25.1°-38.9°), and pincer (≥39°). Repeated-measures analysis of variance compared preoperative with 2-year minimum postoperative International Hip Outcome Tool (iHOT-12) scores. Subsequent analysis of variance determined the effect of acetabular coverage on magnitude of change in scores. RESULTS: Of 437 patients, the only statistical difference between groups was a lower prevalence of acetabuloplasty in the borderline dysplasia group (P = .001). A significant improvement in the preoperative to postoperative iHOT-12 scores for patients with normal acetabular coverage, acetabular undercoverage, and acetabular overcoverage was observed: F(1, 339) = 311.06; P <.001, with no statistical differences in preoperative (P = .505) and postoperative (P <.488) iHOT-12 scores when comparing the groups based on acetabular coverage. Mean iHOT-12 scores increased from 37.3 preoperatively to 68.7 postoperatively (P <.001) in the borderline dysplasia group, from 34.4 to 72 (P <.001) in the normal coverage group, and from 35.3 to 69.4 (P <.001) in the pincer group. These preoperative scores increased by 31.4, 37.8, and 34.1, respectively, with no effect for acetabular coverage on the magnitude of change from preoperative to postoperative iHOT-12 scores: F(2,339) = 1.18; P = .310. Ten patients (2.3%) underwent conversion arthroplasty, and 19 patients (4.4%) underwent revision arthroscopy with no significant effect of acetabular coverage on the incidence of revision or conversion surgery: χ2 (6,433) = 11.535; P = .073. CONCLUSIONS: Lateral acetabular coverage did not influence outcomes from primary hip arthroscopy when performed in patients with low (borderline dysplasia), normal, and high (global pincer FAI) lateral center-edge angle. Borderline dysplasia and moderate global pincer FAI with no or minimal osteoarthritis do not compromise successful 2-year minimum outcomes or survivorship following primary hip arthroscopy when performed by experienced surgeons. LEVEL OF EVIDENCE: Level III, retrospective therapeutic trial.

Minimal Clinically Important Difference and Substantial Clinical Benefit Values for the 12-Item International Hip Outcome Tool.

PURPOSE: To define minimal clinically important difference (MCID) and substantial clinical benefit (SCB) values for the 12-item International Hip Outcome Tool (iHOT-12) in patients undergoing hip arthroscopy for intra-articular pathology. METHODS: This was a retrospective review of prospectively collected data on patients who underwent hip arthroscopy. On initial assessment and follow-up between 335 and 395 days after surgery, subjects completed the iHOT-12 and a categorical self-rating of function (severely abnormal, abnormal, nearly normal, or normal). One-half the standard deviation (SD) of the change in 1-year iHOT-12 scores was used to calculate the MCID. Receiver operator characteristic analysis was performed to determine SCB values. A change in SCB value was determined based on an improvement in the categorical rating of function. Absolute postoperative SCB scores were calculated to determine scores that would be associated with normal function ratings or with abnormal or severely abnormal function ratings. RESULTS: Of 1,034 eligible patients, 733 (71%) met the inclusion criteria. The subjects consisted of 537 female patients (73%) and 196 male patients (27%), with a mean age of 35.3 years (SD, 13 years). At a mean of 352 days (SD, 21 days) after surgery, 536 patients (73%) were in the "improved" group and 197 (27%) were in the "not improved" group. The MCID was 13 points. An SCB change score of 28 points was able to identify patients who improved with high sensitivity (0.79) and specificity (0.72). Scores of 86 points or greater and 56 points or less were the cutoff values found to identify subjects who rated their function as normal and abnormal, respectively, with high sensitivity (0.74 and 0.90, respectively) and specificity (0.82 and 0.86, respectively). CONCLUSIONS: This study provides information to help interpret iHOT-12 scores for a follow-up period ranging between 335 and 395 days with MCID and SCB values of 13 and 28 points, respectively. In addition, a vpatient who scored 86 points or better was likely to have a normal rating of function, whereas a patient with a score of 56 points or less was likely to have an abnormal rating of function. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

A Prospective, Randomized, Controlled Trial Comparing Conservative Treatment With Trunk Stabilization Exercise to Standard Hip Muscle Exercise for Treating Femoroacetabular Impingement: A Pilot Study.

OBJECTIVE: To assess the efficacy of conservative management of women with femoroacetabular impingement (FAI) using trunk stabilization. DESIGN: Randomized controlled trial (level of evidence: I). SUBJECTS: Twenty FAI female patients who met the inclusion FAI criteria. METHODS: A prospective, randomized, controlled study was performed on 20 female patients with symptomatic FAI comprising 2 groups (10 hips in trunk stabilization exercise group vs 10 hips in control group). We evaluated hip range of motion, isometric muscle strength using a handheld dynamometer (µ-TasMF-01; Anima, Co), and patient-reported outcome measures, including modified Harris hip score, Vail hip score, and international hip outcome tool 12 (iHOT12) before and at 4 weeks and 8 weeks after the intervention. RESULTS: There was a significant improvement in the range of motion of hip flexion in the trunk training group detected as early as 4 weeks after the intervention compared with the control group (P < 0.05). Hip abductor strength significantly improved in the trunk training group at 4 weeks after the intervention, whereas it did not improve in the control group (P < 0.05). Vail hip score and iHOT12 were significantly increased at 8 weeks after the intervention in the trunk training group compared with the control group (iHOT12: 78.7 ± 22.4 vs 53.0 ± 22.3; P < 0.01, Vail hip score: 81.6 ± 18.5 vs 61.1 ± 11.6; P < 0.05). There was no significant difference in the modified Harris hip score between both the groups at 4 and 8 weeks after the intervention. CONCLUSIONS: The addition of trunk stabilization exercise to a typical hip rehabilitation protocol improves short-term clinical outcomes and may augment nonoperative and postoperative rehabilitation.

Radiologic Correlation Between the Ischiofemoral Space and Morphologic Characteristics of the Hip in Hips With Symptoms of Dysplasia.

OBJECTIVE: The purpose of this study was to investigate radiologic correlation between the ischiofemoral space and morphologic findings in the hip in patients with symptomatic developmental dysplasia of the hip (DDH), borderline DDH, and femoroacetabular impingement (FAI). MATERIALS AND METHODS: In 84 patients undergoing hip arthroscopic surgery, 108 hips were divided into three groups according to lateral center-edge angle (LCEA): DDH group (LCEA < 20°; 18 hips), borderline DDH group (20° ≤ LCEA < 25°; 26 hips), and FAI group (LCEA ≥ 25°; 64 hips). Ischiofemoral distance was evaluated by radiography and ischiofemoral space and quadratus femoris space by MRI. Software was used to measure the radiographic parameters LCEA, femoral neck-shaft angle, and femoral neck anteversion on preoperative CT scans. RESULTS: Ischiofemoral distance, ischiofemoral space, and quadratus femoris space were significantly smaller in the DDH and borderline DDH groups than in the FAI group. The prevalence of hips with ischiofemoral space < 17 mm was significantly higher in the DDH (10 of 18 patients [56%]) and borderline DDH (8 of 26 patients [31%]) groups than in the FAI group (4 of 64 patients [6%]). In addition, the prevalence of hips with a quadratus femoris space < 8 mm was significantly higher in the DDH (2 of 18 patients [11%]) and borderline DDH (3 of 26 patients [12%]) groups than in the FAI (0 of 64 patients [0%]) group. Femoral neck-shaft angle and femoral neck anteversion were significantly greater in the DDH group than in the FAI group. CONCLUSION: Ischiofemoral impingement syndromes can be considered more likely in patients with DDH than in those with FAI.

Endoscopic resection of acetabular screw tip to decompress sciatic nerve following total hip arthroplasty.

BACKGROUND: Sciatic nerve injuries following total hip arthroplasty are disabling complications. Although degrees of injury are variable from neuropraxia to neurotmesis, mechanical irritation of sciatic nerve might be occurred by protruding hardware. This case shows endoscopic decompression for protruded acetabular screw irritating sciatic nerve, the techniques described herein may permit broader arthroscopic/endoscopic applications for management of complications after reconstructive hip surgery. CASE PRESENTATION: An 80-year-old man complained of severe pain and paresthesias following acetabular component revision surgery. Physical findings included right buttock pain with radiating pain to lower extremity. Radiographs and computed tomography imaging showed that the sharp end of protruded screw invaded greater sciatic foramen anterior to posterior and distal to proximal direction at sciatic notch level. A protruding tip of the acetabular screw at the sciatic notch was decompressed by use of techniques gained from experience performing endoscopic sciatic nerve decompression. The pre-operative pain and paresthesias resolved post-operatively after recovering from anesthesia. CONCLUSIONS: This case report describes the first documented endoscopic resection of the tip of the acetabular screw irritating sciatic nerve after total hip arthroplasty. If endoscopic resection of an offending acetabular screw can be performed in a safe and minimally invasive manner, one can envision a future expansion of the role of hip arthroscopic surgery in several complications management after total hip arthroplasty.

Editorial Commentary: Proximal Hamstring Syndrome: Another Pain in the Buttock.

Proximal hamstring injuries cause buttock pain and may result in significant weakness and sciatic neuralgia. Avulsion ruptures involving 2 or more tendons with >2-cm retraction may benefit from early open surgical repair. More chronic equivalents may benefit from Achilles allograft reconstruction. Chronic proximal hamstring syndrome causing posterior thigh and sit pain may occur from less severe, often repetitive injury to the proximal hamstring origin with secondary sciatic neuralgia from local adhesions or scar entrapment. Recalcitrant cases may benefit from surgical intervention, but the most effective procedure (tenotomy, resection of degenerative tissue with tenotomy vs repair, sciatic neurolysis) has not been established. The role of endoscopic surgery of the proximal hamstring is evolving, but currently may best be indicated for ischial bursectomy, debridement of degenerative tendon tissue, and/or sciatic neurolysis. Although endoscopic proximal hamstring repair is feasible for treating tears with mild retraction, the role of endoscopic (or open) surgery in repair of acute complete tears with <2-cm retraction or less severe injuries (partial tears or complete tears without retraction) is controversial because most of these injuries may respond to nonoperative management. In this setting, perhaps surgical treatment (open or endoscopic) should be reserved for patients who have failed nonsurgical management.

Hip Dysplasia: Prevalence, Associated Findings, and Procedures From Large Multicenter Arthroscopy Study Group.

PURPOSE: To report observational findings of patients with acetabular dysplasia undergoing hip arthroscopy. METHODS: We performed a comparative case series of multicenter registry patients from January 2014 to April 2016 meeting the inclusion criteria of isolated hip arthroscopy, a documented lateral center-edge angle (LCEA), and completion of preoperative patient-reported outcome measures. A retrospective analysis compared range of motion, intra-articular pathology, and procedures of patients with dysplasia (LCEA ≤25°) and patients without dysplasia (LCEA >25°). RESULTS: Of 1,053 patients meeting the inclusion criteria, 133 (13%) had dysplasia with a mean LCEA of 22.8° (standard deviation, 2.4°) versus 34.6° (standard deviation, 6.3°) for non-dysplasia patients. There were no statistically significant differences in preoperative modified Harris Hip Score, International Hip Outcome Tool-12 score, or visual analog scale score (pain). Cam deformity occurred in 80% of dysplasia patients. There was a significant difference in internal rotation between the dysplasia (21°) and non-dysplasia groups (16°, P < .001). Mean internal rotation (33.5°; standard deviation, 15.6°) of the dysplastic subjects without cam morphology was greater than that of the dysplastic patients with cam morphology (18.5°; standard deviation, 11.6°; P < .001). Hypertrophic labra were found more commonly in dysplastic (33%) than non-dysplastic hips (11%, P < .001). Labral tears in patients with dysplasia were treated by repair (76%), reconstruction (13%), and selective debridement (11%); labral treatments were not significantly different between cohorts. The most common nonlabral procedures included femoroplasty (76%) and synovectomy (73%). There was no significant difference between the dysplasia and non-dysplasia groups regarding capsulotomy types and capsular closure rates (96% and 92%, respectively). CONCLUSIONS: Dysplasia, typically of borderline to mild severity, comprises a significant incidence of surgical cases (13%) by surgeons performing high-volume hip arthroscopy. Despite having similar preoperative pain and functional profiles to patients without dysplasia, dysplasia patients may have increased flexed-hip internal rotation. Commonly associated cam morphology significantly decreases internal rotation. Arthroscopic labral repair, femoroplasty, and closure of interportal capsulotomy are the most commonly performed procedures. LEVEL OF EVIDENCE: Level III, therapeutic comparative case series.

Sex-Dependent Differences in Preoperative, Radiographic, and Intraoperative Characteristics of Patients Undergoing Hip Arthroscopy: Results From the Multicenter Arthroscopic Study of the Hip Group.

PURPOSE: To compare preoperative, radiographic, and intraoperative findings between male and female patients undergoing hip arthroscopy. METHODS: We performed a retrospective review of a multicenter registry of patients undergoing hip arthroscopy between January 2014 and January 2017. Perioperative data from patients who consented to undergo surgery and completed preoperative patient-reported outcome questionnaires were analyzed to determine the effect of sex on preoperative symptoms, patient-reported outcomes, radiographic measures, and surgical procedures. RESULTS: A total of 1,437 patients (902 female and 535 male patients) with a mean age of 34 years were enrolled in the study. Female patients reported greater pain preoperatively on a visual analog scale (55.42 vs 50.40, P = .001) and deficits in functional abilities as per the modified Harris Hip Score (53.40 vs 57.83, P < .001) and International Hip Outcome Tool 12 (31.21 vs 38.51, P = .001) than male patients. There was a significant difference in the alpha angle (67.6° in male patients vs 59.5° in female patients, P < .001) corresponding with a higher prevalence of cam deformity in male patients (94.6% vs 84.5%, P < .001). Male patients had less range of motion in flexion (-5.67°, P < .001), internal rotation (-8.23°, P < .001), and external rotation (-4.52°, P < .001) than female patients. Acetabular chondroplasty was performed in 58% of male patients versus 40.2% of female patients (P < .001). Acetabuloplasty was performed in 59.1% of male patients versus 43.9% of female patients (P < .001). CONCLUSIONS: Male and female patients undergoing hip arthroscopy differ statistically in terms of preoperative hip function, hip morphology, and self-reported functional deficits, as well as the prevalence of surgical procedures. However, they do not differ significantly in terms of symptom localization, duration, or onset. The observed differences in preoperative functional scores between sexes, although statistically significant, may not represent clinically meaningful differences. LEVEL OF EVIDENCE: Level III, retrospective cross-sectional study.