Radiographic Evidence Of Femoroacetabular Impingement Research Articles

Characterizing femoroacetabular impingement in professional Nordic Skiers

ABSTRACT Objective Studies have shown a high prevalence of femoroacetabular impingement (FAI) among elite athletes yet there is a paucity of data on FAI in Nordic skiers. The purpose of this study was to determine the prevalence of radiographic FAI in professional Nordic Combined Skiers and Ski jumpers compared to controls and assess functional outcomes including hip range of motion (ROM) and pain in patients with radiographic evidence of FAI compared to those without it. Methods A cohort of elite Nordic Skiers underwent medical history, physical examination, and pelvic radiographs at their visit with a fellowship-trained sports medicine physician. On pelvis radiographs, Alpha angle>55 degrees was deemed cam-positive, and positive crossover signs, Tönnis<0, or LCEA>40 were deemed pincer positive. Further stratification was performed by sex, ski event type, hip pain, presence of cam lesions, and presence of pincer lesions. Spearman correlation matrix was performed to measure the association between radiographic measurements and ROM. Results Nineteen Nordic skiers and nineteen age, sex, and BMI matched controls were included in the study. There were no significant differences in age, sex, BMI, and hip pain between groups. While Nordic skiers demonstrated decreased ROM bilaterally on external rotation compared to controls, skiers had larger ROM bilaterally on extension, abduction, adduction compared to controls. Skiers were significantly more likely to have bilateral crossover sign and alpha angles>55 compared to controls. Subgroup analysis showed that Cam positive patients had higher flexion and adduction ROM and pincer positive patients had significantly higher flexion and abduction ROM compared to patients without cam and pincer lesions respectively. Patients with hip pain had significantly lower right hip abduction ROM compared to patients without hip pain. No significant correlations were seen between radiographic measurements and ROM. Conclusion Similar to other elite ‘hip heavy’ sport athletes, Nordic skiers gave a notably higher prevalence of radiographic cam and pincer type morphology and significantly higher ROM compared to nonathletic controls. Clinicians evaluating Nordic skiers should be aware of these baseline findings with respect to a possible elevated long-term risk of symptomatic FAI in these athletes as well as other conditions related to radiographic FAI.

Hip Strength Before and After Arthroscopic Femoroacetabular Impingement Surgery.

Femoroacetabular impingement (FAI) and labral pathology are associated with pain, decreased function, and hip strength deficits. Existing data are in conflict regarding when hip strength normalizes following arthroscopic treatment of FAI. The objective of this study was to identify preoperative hip strength relative to the contralateral hip not undergoing surgery as well as when postoperative strength in 4 functional muscle groups normalizes following arthroscopic treatment of FAI. Ninety-eight individuals with radiographic evidence of FAI and labral pathology underwent arthroscopic labral repair. Pre-surgical hip strength testing was performed in the symptomatic "surgical hip" and the contralateral "non-surgical hip." Hip strength measurements were repeated at 8 and 16 weeks postoperatively. Significant preoperative hip strength deficits were noted in the surgical hip compared with the non-surgical hip in flexion, extension, and adduction. At 8 weeks postoperatively, hip strength in the surgical hip improved to being equivalent to that in the non-surgical hip in adduction and extension, remained equivalent to that of the non-surgical hip in abduction, and decreased in flexion relative to the non-surgical hip. At 16 weeks, hip strength remained equivalent in the surgical hip and the non-surgical hip in abduction and adduction, but the surgical hip exceeded the non-surgical hip in extension. While flexion strength improved between 8 and 16 weeks postoperatively for the surgical hip, it had not fully recovered to that of the non-surgical hip. Using a structured postoperative rehabilitation protocol, abduction strength was maintained at 8 weeks postoperatively, while adduction and extension strength had improved to those of the non-surgical hip. At 16 weeks postoperatively, hip abduction and adduction had strength equivalent to those of the non-surgical hip. Despite preoperative improvement, flexion of the surgical hip lagged behind that of the non-surgical hip 16 weeks postoperatively. [Orthopedics. 2021;44(3):148-153.].

Decreased Hip Labral Width Measured via Preoperative Magnetic Resonance Imaging Is Associated With Inferior Outcomes for Arthroscopic Labral Repair for Femoroacetabular Impingement

To determine the association between labral width as measured on preoperative magnetic resonance imaging (MRI) and hip-specific validated patient self-reported outcomes at a minimum of 2 years' follow-up. We performed an institutional review board-approved retrospective review of prospectively gathered hip arthroscopy patients from 2010 to 2017. The inclusion criteria were defined as patients aged 18 to 65 years with radiographic evidence of femoroacetabular impingement who underwent a primary labral repair and had a minimum of 2 years' clinical follow-up. The exclusion criteria were defined as inadequate preoperative imaging, prior hip surgery, Tönnis grade 1 or higher, or lateral center-edge angle lower than 25°. An a priori power analysis was performed. MRI measurements of labral width were conducted by 2 blinded, musculoskeletal fellowship-trained radiologists at standardized "clock-face" locations using a previously validated technique. Outcomes were assessed using the Harris Hip Score (HHS), modified Harris Hip Score (mHHS), and Non-arthritic Hip Score (NAHS). For the mHHS, scores of 8 and 74 were used to define the minimal clinically important difference and patient acceptable symptomatic state, respectively. Patients were divided into groups by a labral width less than 1 SD below the mean (hypoplastic) or widths above 1 SD below the mean. Statistical analysis was performed using linear and polynomial regression; the Mann-Whitney U, χ2, and Fisher exact tests; and intraclass correlation coefficient testing. A total of 103 patients (107 hips) met the inclusion criteria (mean age, 39.4 ± 17 years; body mass index, 25.0 ± 4; 51% right sided; 68% female patients; mean follow-up, 76.5 ± 19.1 months [range, 30.0-113.0 months]). Mean labral width at the 11:30 clock-face position (indirect rectus), 3-o'clock position (psoas U), and 1:30 clock-face position (point halfway between the 2 aforementioned positions) was 7.1 ± 2.2 mm, 7.0 ± 2.0 mm, and 5.5 ± 1.9 mm, respectively. Intraclass correlation coefficient agreements were good to excellent between readers at all positions (0.83-0.91, P < .001). The preoperative HHS, mHHS, and NAHS were not statistically significantly different (P > .05) between the 2 groups. Sex, laterality, and body mass index were not predictive of outcomes (P>.05). The postoperative HHS, mHHS, and NAHS were found to be significantly lower in the hypoplastic group at each location tested (P < .01), including the mHHS at the 11:30 clock-face position (69 vs 87), 3-o'clock position (70 vs 87), and 1:30 clock-face position (71 vs 87). The proportion of patients with hypoplastic labra who reached the minimal clinically important difference was significantly lower (P < .001) at the 11:30 clock-face position (50% vs 91%), 3-o'clock position (56% vs 90%), and 1:30 clock-face position (58% vs 91%) in comparison to the non-hypoplastic labrum group. The proportion of patients with hypoplastic labra above the patient acceptable symptomatic state was significantly lower (P < .001) at the 11:30 clock-face position (44% vs 83%), 3-o'clock position (37.5% vs 84%), and 1:30 clock-face position (42% vs 85%) in comparison to the non-hypoplastic labrum group. Linear regression modeling was not significant at any position (P > .05). Polynomial regression was significant at the 11:30 clock-face position (R2= 0.23, P < .001), 3-o'clock position (R2=0.17, P<.001), and 1:30 clock-face position (R2= 0.26, P < .004). Hip labral width less than 1 SD below the mean measured via preoperative MRI was associated with significantly worse functional outcomes after arthroscopic labral repair and treatment of femoroacetabular impingement. The negative relation between labral width and outcomes may be nonlinear. Level IV, case series with subgroup analysis.

Decreased Hip Labral Width Measured via Preoperative MRI is Associated with Inferior Outcomes for Arthroscopic Labral Repair

Objectives:There are few pre-operative prognostic factors for hip labral repair outcomes. The objective of this study was to determine if hip labrum width measured on MRI was predictive of outcomesMethods:A retrospective review of prospectively gathered hip arthroscopy patients from 2010 to 2017 was performed. Inclusion criteria was defined as: patients >18 years old with radiographic evidence of femoroacetabular impingement who underwent a primary labral repair with >2 years of follow-up. Exclusion criteria was defined as: inadequate imaging, prior hip surgery, Tonnis grade ≥2 or lateral central edge angle <25 degrees. An a-priori power analysis was performed. MRI measurements of labral width were conducted by two blinded musculoskeletal fellowship-trained radiologists at standardized “clockface” locations using a previously validated technique. Outcomes were assessed using the Harris Hip Score (HHS), Modified HHS (mHSS), and NonArthritic Hip Score (NAHS). For mHHS, a minimal clinically important difference (MCID) and Patient Acceptable Symptomatic State (PASS) of 8 and 74 were used, respectively. Patients were divided into groups by labral width of ≤4mm and >4mm. Statistical analysis was performed using: linear and polynomial regression, Mann-Whitney U, Fischer exact, and interclass-correlation coefficients (ICC) testingResults:One hundred and three patients (107 hips) met criteria (mean age 39.4years+/-17, BMI 25.0+/-4, 51%right-sided, 68%female). Mean labrum measurements and number of patients with ≤4mm labrums at the 12:00 (indirect rectus), 3:00 (Psoas U), and 1:30 (point ½ between) positions were 7.1mm+/-2.2; 15 labrums≤4mm, 7.0 mm+/-2.0;13 labrums≤4mm, and 5.5+/-1.9; 27 labrums≤4mm, respectively. ICC agreements were good to excellent between readers at all positions (0.83-0.91,p<0.001). Pre-operative HHS, mHHS, and NAHS were not statistically different (p>0.05). Sex, laterality, and BMI had no significant effect on outcomes (p>0.05).HHS, mHHS, and NAHS scores were found to be significantly lower in the ≤4mm group at each location tested (p<0.001); including mHHS at the 12:00 (67vs87), 3:00, (69vs87) and 1:30 (74vs88) positions. The proportion of ≤4mm patients that reached MCID was significantly lower(p<0.001) at the 12:00 (47%vs91%), 3:00 (54%vs89%) and 1:30 (63%vs93%) positions. The proportion of ≤4mm patients above PASS was significantly lower (p<0.001) at the 12:00 (40%vs84%), 3:00 (31%vs84%) and 1:30 (52%vs86%) positions.Linear regression modelling was not significant at any position (p>0.05). Polynomial regression was significant at the 12:00 (R2=0.23,p<0.001), 3:00 (R2=0.17,p<0.001), and 1:30 (R2=0.26,p<0.001).Conclusion: A non-linear relationship may exist between labral width and patient outcomes following labral repair. Labrum width of ≤4mm measured via MRI may negatively impact labral repair outcomes. Future research may determine if torn labrums ≤4mm should be reconstructed instead of repaired.

Biomechanics during cross-body lunging in individuals with and without painful cam and/or pincer morphology

BackgroundFemoroacetabular impingement is a patho-mechanical hip condition that can lead to restrictions in hip motion, particularly in end-range hip flexion, adduction and/or internal rotation. Radiographic evidence of femoroacetabular impingement – cam and/or pincer morphology - is prevalent in the general and athletic populations. There is, however, a lack of studies that have analyzed the performance of sport-specific movements in people possessing these morphologies. Therefore, the purpose of this study was to compare cross-body lunge biomechanics between individuals with and without painful cam and/or pincer morphology. MethodsThis was an exploratory, cross-sectional study where nine participants with cam and/or pincer morphology and symptoms, thirteen participants with asymptomatic cam and/or pincer morphology, and eleven pain-free controls performed the cross-body lunge during a single session. Trunk, pelvis, hip, knee and ankle kinematics, as well as hip, knee and ankle kinetics and vertical ground reaction forces were examined. FindingsOverall, the groups performed the movement similarly, with most variables statistically similar between groups. However, pelvis sagittal plane excursion throughout the entire cross-body lunge was significantly larger in those with cam and/or pincer morphology and symptoms compared to those with asymptomatic cam and/or pincer morphology (P = .046, effect size = 0.98). InterpretationThe results of this study show that cross-body lunge performance is similar across individuals with and without painful cam and/or pincer morphology. However, future research should aim to better understand pelvis biomechanics during sporting activities, as pelvis sagittal plane excursion may have important implications in rehabilitation and sport performance.

Hip Arthroscopy for Atypical Posterior Hip Pain: A Comparative Matched-Pair Analysis

Background: Femoroacetabular impingement (FAI) most commonly manifests as anterior groin pain. Patients occasionally have posterior pain but otherwise have clinical and radiographic evidence of FAI. Purpose: To compare outcomes of hip arthroscopy for FAI in patients with atypical posterior pain versus a matched group with the typical anterior pain presentation. Study Design: Cohort study; Level of evidence, 3. Methods: Patients undergoing primary hip arthroscopy for FAI were identified from a clinical repository between January 2012 and 2014. Of 503 patients during the study period, 31 (6.2%) had posterior hip or buttock pain reproduced with flexion, adduction, and internal rotation (FADDIR) and were classified as “atypical,” while those with anterior hip or groin pain were classified as “typical.” Atypical patients were matched in a 1:2 cohort to the typical group based on sex, age, and body mass index (BMI). Postoperative patient-reported outcomes included visual analog scale (VAS) for pain, modified Harris Hip Score (mHHS), and Hip Outcome Scores with Activities of Daily Living (HOS-ADL) and Sports-Specific (HOS-SS) subscales. Results: Of the 31 atypical patients, 28 (90.3%) were available for a minimum 2-year follow-up (mean ± SD, 2.6 ± 0.6 years). These patients were matched with 56 typical patients. No differences were noted between typical and atypical cohorts in preoperative demographic or radiographic parameters. Postoperatively, both groups demonstrated significant improvements in mHHS (atypical 60.1 ± 12.4 to 78.8 ± 12.9; typical 60.0 ± 12.3 to 76.9 ± 13.6; P < .001), HOS-ADL (atypical 68.5 ± 17.0 to 88.6 ± 11.0; typical 69.2 ± 17.1 to 86.8 ± 14.7; P < .001), and HOS-SS (atypical 42.0 ± 25.5 to 71.0 ± 26.2; typical 44.4 ± 24.9 to 71.3 ± 27.3; P < .001). No differences were found in 2-year score improvements between the atypical and typical cohorts (mHHS 18.7 ± 13.4 vs 16.9 ± 13.1, P = .48; HOS-ADL 20.1 ± 16.8 vs 17.6 ± 14.6, P = .19; HOS-SS 29.0 ± 30.2 vs 26.9 ± 27.3, P = .93). Also, no significant differences were found in VAS pain improvement (5.0 ± 3.2 vs 5.6 ± 2.8, P = .56) or postoperative satisfaction (79.5 ± 5.5 vs 77.5 ± 4.1, P = .78). Conclusion: Atypical posterior hip pain is an uncommon presentation of FAI. Patients demonstrate similar significant improvements after hip arthroscopy in outcome scores, postoperative pain, and satisfaction compared with patients who have classic anterior groin pain.

Sonographic Prevalence of Groin Hernias and Adductor Tendinopathy in Patients With Femoroacetabular Impingement

Background: Femoroacetabular impingement (FAI) is a common debilitating condition that is associated with groin pain and limitation in young and active patients. Besides FAI, various disorders such as hernias, adductor tendinopathy, athletic pubalgia, lumbar spine affections, and others can cause similar symptoms. Purpose: To determine the prevalence of inguinal and/or femoral herniation and adductor insertion tendinopathy using dynamic ultrasound in a cohort of patients with radiographic evidence of FAI. Study Design: Case series; Level of evidence, 4. Methods: This retrospective study consisted of 74 patients (36 female and 38 male; mean age, 29 years; 83 symptomatic hips) with groin pain and radiographic evidence of FAI. In addition to the usual diagnostic algorithm, all patients underwent a dynamic ultrasound examination for signs of groin herniation and tendinopathy of the proximal insertion of the adductors. Results: Evidence of groin herniation was found in 34 hips (41%). There were 27 inguinal (6 female, 21 male) and 10 femoral (9 female, 1 male) hernias. In 3 cases, inguinal and femoral herniation was coexistent. Overall, 5 patients underwent subsequent hernia repair. Patients with groin herniation were significantly older than those without (33 vs 27 years, respectively; P = .01). There were no significant differences for any of the radiographic or clinical parameters. Tendinopathy of the proximal adductor insertion was detected in 19 cases (23%; 11 female, 8 male). Tendinopathy was coexistent with groin herniation in 8 of the 19 cases. There were no significant differences for any of the radiographic or clinical parameters between patients with or without tendinopathy. Patients with a negative diagnostic hip injection result were more likely to have a concomitant groin hernia than those with a positive injection result (80% vs 27%, respectively). Overall, 38 hips underwent FAI surgery with satisfactory outcomes in terms of score values and subjective improvement. Conclusion: The results demonstrate that groin herniation and adductor insertion tendinopathy coexist frequently in patients with FAI. Although the clinical effect is yet unclear, 5 patients underwent hernia repair. Dynamic ultrasound is a useful tool to detect such pathological abnormalities. Diagnostic hip injections can be helpful to differentiate between the sources of pain.

Radiographic Evidence of Femoroacetabular Impingement in Athletes With Athletic Pubalgia

Background:Two of the most common causes of groin pain in athletes are femoroacetabular impingement (FAI) and athletic pubalgia. An association between the 2 is apparent, but the prevalence of radiographic signs of FAI in patients undergoing athletic pubalgia surgery remains unknown. The purpose of this study was to determine the prevalence of radiologic signs of FAI in patients with athletic pubalgia.Hypothesis:We hypothesized that patients with athletic pubalgia would have a high prevalence of underlying FAI.Study Design:Case series.Level of Evidence:Level 4.Methods:A retrospective review of all patients evaluated at our institution with athletic pubalgia who underwent surgical treatment (ie, for sports hernia) from 1999 to 2011 was performed. The radiographs of patients with athletic pubalgia were reviewed for radiographic signs of FAI. Alpha angles were measured using frog-leg lateral radiographs. Pincer lesions were identified by measuring the lateral center-edge angle and identifying the presence of a “crossover” sign on anteroposterior radiographs. Phone follow-up was performed 2 years or more after the initial sports hernia surgery to evaluate recurrent symptoms.Results:Forty-three patients underwent 56 athletic pubalgia surgeries. Radiographic evidence of FAI was identified in at least 1 hip in 37 of 43 patients (86%). Cam lesions were identified in 83.7% of the population; the alpha angle averaged 66.7° ± 17.9° for all hips. Pincer lesions were present in 28% of the hips. Eight patients had recurrent groin pain, 3 patients had revision athletic pubalgia surgery, and 1 had hip arthroscopy.Conclusion:The study demonstrates a high prevalence of radiographic FAI in patients with athletic pubalgia.Clinical Relevance:Underlying FAI may be a cause of continued groin pain after athletic pubalgia surgery. Patients with athletic pubalgia should be evaluated closely for FAI.

Is Prophylactic Surgery for Femoroacetabular Impingement Indicated?

Background: This is a systematic review to determine if prophylactic surgical intervention for asymptomatic patients with radiographic evidence of femoroacetabular impingement (FAI) is warranted to prevent early degenerative joint disease of the hip. Methods: A systematic search was performed from 1965 to 2013 in PubMed and EMBASE. Inclusion criteria were prospective or retrospective studies comparing skeletally mature asymptomatic patients with radiographic evidence of FAI treated with prophylactic hip arthroscopic surgery versus nonoperative management. A total of 840 references were identified from the searches. After detailed eligibility screening, none of the references met the eligibility criteria. Results: No trials were identified that met the criteria for inclusion in the review. Conclusion: There is a lack of available evidence to support surgical intervention for the treatment of FAI in asymptomatic patients. This article attempts to address this dilemma by reviewing the available literature to answer several questions that would indirectly address the topic. First, what is the prevalence of FAI in the asymptomatic population? Second, what is the natural history of FAI if left untreated? Upon reviewing these issues, the authors’ conclusion parallels that of the systematic review: Current evidence does not support prophylactic surgery for asymptomatic FAI in the vast majority of cases. However, limited evidence suggests that asymptomatic patients who have previously undergone total hip arthroplasty for FAI-induced osteoarthritis of the contralateral hip are at a significantly increased risk for early degenerative joint disease. Further research is needed to better clarify surgical indications.

Symptomatic Sacroiliac Joint Disease and Radiographic Evidence of Femoroacetabular Impingement

Symptomatic sacroiliac (SI) joint disease is poorly understood. The literature provides no clear aetiology for SI joint pathology, making evaluation and diagnosis challenging. We hypothesised that patients with documented sacroiliac pain might provide insight into the aetiology of these symptoms. Specifically, we questioned whether SI joint symptoms might be associated with abnormal hip radiographs. We reviewed the pelvic and hip radiographs of a prospectively collected cohort of 30 consecutive patients with SI joint pathology. This database included 33 hips from 30 patients. Radiographic analysis included measurements of the lateral centre edge angle, Tönnis angle, and the triangular index, of the ipsilateral hip. Evidence for retrotorsion of the hemipelvis was recorded. Hips were graded on the Tönnis grading system for hip arthrosis. In this cohort 14/33 (42%) of hips had evidence of significant osteoarthrosis indicated by Tönnis grade 2 or greater and 15/33 (45%) displayed subchondral cyst formation around the hip or head neck junction. In assessing acetabular anatomy, 21% (7/33) had retroversion, 12% (4/33) had a lateral centre edge angle >40° with 3% (1/33) >45°. Tönnis angle was <0° in 27% (9/33). Coxa profunda and acetabuli protrusio were present in 47% (17/33) and 3% (1/33), respectively. When femoral head morphology was assessed, 33% (11/33) showed evidence of cam impingement. Overall, 76% (25/33) had at least one abnormality on their hip radiograph. A significant number of patients meeting strict diagnostic criteria for SI joint pain had radiographic evidence of femoroacetabular impingement (FAI) and hip arthrosis. The clinician should maintain FAI in the differential diagnosis when investigating patients with buttock pain.

Assessment of osteoarthritis in hips with femoroacetabular impingement using delayed gadolinium enhanced MRI of cartilage

To determine the feasibility of assessing early osteoarthritis (OA) in hips with femoroacetabular impingement (FAI) using delayed Gadolinium enhanced MRI of Cartilage (dGEMRIC). Thirty-seven hips in 30 patients who had a dGEMRIC scan and radiographic evidence of FAI were identified. Clinical symptoms were assessed. Radiographic measurements were performed to determine acetabular and femoral morphology. The severity of radiographic OA was determined using Tönnis grade and minimum joint space width (JSW). On MRI, the alpha angle was measured on the sagittal oblique slices. Correlations between dGEMRIC index, patient symptoms, morphologic measurements, radiographic OA, and age were determined. Significant correlations were observed between dGEMRIC index, pain (P < 0.05), and alpha angle (P < 0.05). The correlation of dGEMRIC with alpha angle suggests that hips with more femoral deformity show signs of early OA. The results of osteoplasty for FAI depend on the amount of pre-existing OA in the joint. dGEMRIC may be a useful technique for diagnosis and staging of early osteoarthritis in hips with impingement.

Revision Hip Arthroscopy

Background Hip arthroscopy has become increasingly popular; however, little is known about revision hip arthroscopy. Hypothesis Revision hip arthroscopy is associated with unaddressed femoroacetabular impingement. The purpose of this study was to describe reasons for revision hip arthroscopy. Study Design Case series; Level of evidence, 4. Methods Between March 2005 and March 2006, 37 revision hip arthroscopies were performed by the senior author. Data were collected through retrospective review of clinical and operative notes. Results All patients required revision surgery because of persistent hip pain. There were 25 women and 12 men with an average age of 33 years (range, 16-53 years). The average time from prior surgery to revision was 20.5 months (range, 2.9-84 months). Common findings among patients needing revision were hip pain, decreased range of motion, and functional disability. The average modified Harris Hip Score was 53 (range, 22-99). Thirty-six patients had radiographic evidence of femoroacetabular impingement at the time of revision. Revision procedures included 34 (95%) for femoroacetabular impingement, 32 (87%) for labral lesions, 26 (70%) for a chondral defect, 23 (62%) for lysis of adhesions, and 13 (35%) for previously unaddressed instability. Two patients had total hip arthroplasty after revision, and 3 patients required further revision. Of the remaining 32 patients, early follow-up was obtained on 27 (84%) at an average of 12.7 months postoperatively (range, 6-19 months). Outcomes showed patients regained some of their lost function within the first year. Conclusion Patients commonly required revision hip arthroscopy because of persistent impingement.

Influence of Femoroacetabular Impingement on Results of Hip Arthroscopy in Patients with Early Osteoarthritis

To ascertain whether better results could be obtained using hip arthroscopy, we retrospectively reviewed the radiographic and clinical aspects of anterior femoroacetabular impingement in 43 patients diagnosed with early osteoarthritis with acetabular labral tears who previously had arthroscopic treatment. The average followup was 50 months. The patients were divided into two groups: patients who had no osteoarthritis seen on simple radiographs, but had degenerative changes of the labrum and cartilage seen on magnetic resonance arthrograms and arthroscopy, and patients who had osteoarthritic findings seen on simple radiographs. Both groups were examined retrospectively for signs of anterior femoroacetabular impingement at the acetabulum and proximal femur. Postoperative improvement was evaluated using the Japanese Orthopaedic Association pain score. Six of 21 patients in Group I and 12 of 22 of patients in Group II showed radiographic evidence of femoroacetabular impingement. The score improved from 0.76 preoperatively to 2.38 postoperatively in Group I and from 0.75 preoperatively to 1.90 postoperatively in Group II. Arthroscopic débridement produced improved results seen during short-term and midterm followups. However, in patients with femoroacetabular impingement the results were considered inadequate. We found that arthroscopic treatment of osteoarthritis of the hip fails if there is detectable femoroacetabular impingement.