[Comparative study of ultrasound and magnetic resonance imaging in the diagnosis of asymptomatic anterosuperior acetabular labrum tears].

OBJECTIVE: To explore the diagnostic value of ultrasound for asymptomatic anterosuperior acetabular labral tears (ALT). METHODS: From August 2018 to February 2020, a total of 64 asymptomatic volunteers (101 hips) were recruited to complete 3.0T magnetic resonance imaging (MRI) and ultrasound examination. Among these asymptomatic volunteers, 31 were male and 33 were female, with the median age 35 (32, 39) years. Using 3.0T MRI findings as golden standard, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of ultrasound were calculated. RESULTS: The results showed the presence of unilateral or bilateral ALT in 33 (51.56%) asymptomatic vo-lunteers with a total of 47 hips (46.53%). Of the 37 asymptomatic volunteers with bilateral hip MRI examination, 14 had bilateral ALT and 8 had unilateral ALT. Of the 27 asymptomatic volunteers who underwent unilateral hip MRI, 11 had ALT. Of the 33 asymptomatic volunteers with labral tears, 11 were male and 22 were female, with 30 right hips and 17 left hips. The median age was 36 (33, 40) years in the ALT group and 34 (32, 38) years in the non-ALT group. There was no significant difference in age between the two groups (P > 0.05). In the asymptomatic population, the abnormal anterosuperior acetabular labrum manifestations on ultrasound were intra-labrum cleft in 26 cases, labral heterogeneous echogenicity in 25 cases, paralabral cysts in 2 cases, and labral focal hyperechoic area in 12 cases. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy for ALT diagnosed by ultrasound were 73.53%, 67.16%, 53.19%, 83.33% and 69.31%, respectively. The cross- sectional area (CSA) of the anterosuperior acetabular labrum was 0.20 (0.15, 0.24) cm2 in this study. The labral median CSA of the ALT group and non-ALT group were 0.22 (0.17, 0.28) cm2 and 0.17 (0.14, 0.21) cm2, respectively, with a statistically significant difference (P < 0.001). CONCLUSION: The ALT are common findings in asymptomatic volunteers on MRI. Intra-labrum cleft and labral heterogeneous echogenicity are common ultrasonographic signs in asymptomatic volunteers with ALT. The labra were more swollen in the asymptomatic volunteers with ALT compared to those without ALT.

Acetabular Labral Tear with a Missed Posterior Wall Fracture in an Adolescent Athlete: A Case Report.

CASE: We present an adolescent contact-sport athlete presenting with hip pain after a traumatic in-play event. After delayed clinical improvement, a magnetic resonance arthrogram (MRA) revealed a posterior acetabular labral tear and the patient was referred for arthroscopic repair. However, subsequent critical interpretation of the MRA demonstrated a missed concomitant posterior acetabular wall fracture, which was later confirmed with computed tomography. CONCLUSION: Despite the low incidence of acetabular fractures in adolescents, this case report highlights the importance of maintaining clinical suspicion in young athletes after a traumatic injury, recognizing the association with labral tears, and acknowledging the limitations of certain imaging modalities.

Iatrogenic Articular Cartilage Injury in Arthroscopic Hip and Knee Videos and the Potential for Cartilage Cell Death When Simulated in a Bovine Model.

PURPOSE: To determine the incidence and characterize the severity of iatrogenic cartilage injuries. METHODS: Technique videos of arthroscopic femoral acetabular impingement procedures and meniscus repairs on VuMedi (n = 85) and Arthroscopy Techniques (n = 45) were reviewed and iatrogenic cartilage injuries were identified and graded (minor, intermediate, and major injury) by 2 independent reviewers. To demonstrate that even minor injuries on a cellular scale result in damage, a bovine osteochondral explant was used to create comparable minor iatrogenic injuries at varied forces that do not disrupt the articular surface (1.5 N, 2.5 N, and 9.8 N). Dead chondrocytes at the site of injury were stained with ethidium homodimer-2 and imaged with an Olympus FV1000 confocal microscope. χ2 tests were used for analysis; all results with P < .05 were considered significant. RESULTS: In total, 130 videos of arthroscopic meniscus and femoral acetabular impingement procedures were analyzed and the incidence of iatrogenic cartilage injury was 73.8%. There were 110 (70.0%) minor, 35 (22.3%) intermediate, and 11 (7.0%) major iatrogenic injuries. All forces tested in the minor injury bovine model resulted in chondrocyte death at the site of contact. CONCLUSIONS: Iatrogenic articular cartilage injuries are common in arthroscopy, occurring in more than 70% of the surgeon-published instructional videos analyzed. At least some chondrocyte death occurs with minor simulated iatrogenic injuries (1.5 N). CLINICAL RELEVANCE: The high rate of cartilage damage during arthroscopic technique videos likely under-represents the true incidence in clinical practice. Cell death occurs in the bovine minor injury model with minimal contact forces. This suggests iatrogenic cartilage damage during arthroscopy could contribute to clinical outcomes.

MRI hip findings in asymptomatic professional rugby players, ballet dancers, and age-matched controls.

AIM: To investigate hip magnetic resonance imaging (MRI) findings in asymptomatic professional male rugby players and male ballet dancers compared to age-matched controls. MATERIALS AND METHODS: After ethics committee approval and consent from participants, 11 professional rugby players, 10 professional ballet dancers, and 10 controls completed activity and symptom questionnaires and underwent 3 T MRI of their self-declared dominant hip. Each scan was independently scored by two musculoskeletal radiologists for multiple features, including: joint morphology, acetabular labrum appearance, cartilage loss, and capsular thickness. Clinical and MRI features were assessed for variance by group using one-way analysis of variance (ANOVA) tests and Tukey post-hoc pairwise comparison of means. RESULTS: Labral tear prevalence was 87% with no significant difference between groups (p>0.05). Rates of paralabral cysts were significantly higher in ballet dancers (50%), compared to rugby players (0%) and controls (10%; p=0.01). Acetabular cartilage loss was present in 54% with no significant differences between groups. Superior capsular thickness was significantly greater in ballet dancers (5.3 mm) compared to rugby players (3.8 mm) and controls (3.8 mm; p=0.03). CONCLUSION: Despite the difference in type of activity between groups, there were equally high rates of labral tears and acetabular cartilage loss, questioning the role that sport plays in the development of these findings and their relationship to symptoms. The focally increased superior capsular thickness in ballet dancers may be an adaptive response to extreme ranges of movement.

Findings and Management of the Rare Caput Flexum Deformity of the Hip: A Case Report.

CASE: A 10-year-old girl presented after possible occult hip trauma, with shortening of the leg being the initial clinical symptom, followed by motion-dependent pain. She had limited external rotation in extension with anterior apprehension. Radiographically, the deformity was an anterior tilt of the epiphysis with coxa vara. Surgery included surgical dislocation using a retinacular flap for the anterior open wedge femoral neck osteotomy for extension and posterior translation, with an excellent 4.5-year clinical outcome. CONCLUSIONS: Caput flexum is a rare deformity with localized premature closure of the anterior growth plate of the hip. To avoid secondary impingement, an osteotomy was successfully placed close to the deformity.

Clinical utility of virtual noncalcium dual-energy CT in imaging of the pelvis and hip.

Dual-energy virtual noncalcium images are increasingly used to identify marrow edema which accompanies bony pelvic injuries and marrow pathology obscured by cancellous bone. We present a clinical perspective of our experience using virtual noncalcium images in the work up of pelvic osseous pathology.

Articular and peri-articular hip lesions in soccer players. The importance of imaging in deciding which lesions will need surgery and which can be treated conservatively?

Soccer is one of the most popular sports worldwide engaging millions of participants each year. During play, injuries occur rather frequently and most of them involve the hip joint and the surrounding structure. In professional athletes, injuries are often complex scenarios and in the case of misdiagnosis, patients' return to play is delayed or it may progress to a more serious injury with consequent damage for their career and for the soccer team. The most frequent articular pathologies are Femoro-acetabular impingement and labral tears. Stress fracture, avulsion, ischiofemoral impingement, subspine impingement, athletic pubalgia, muscle injuries and Morel-Levallèe lesion are the most frequent hip peri-articular pathologies whereas snapping hip may be both intra- or extra-articular pathology. With an increasing number of football players, the radiologist plays a crucial role in the detection and characterization of the extent of the injuries. This article reviews the current imaging concepts frequently seen in injuries around the hips of professional football players focusing in particular on the most suitable therapeutic approaches, whether surgical or conservative.

COMPARATIVE ANALYSIS OF WHOLE CARTILAGE TISSUE THERMOSTABILITY IN DISEASED PATIENTS VERSUS INJURED PATIENTS.

We conducted comparative thermodynamic analysis of femoral cartilages tissue of injured (healthy) patients and patients with congenital hip dislocation. It is shown, that temperature which corresponds to maximum of heat absorption peak of femoral cartilages tissue of diseased patient is on 6.4oC lower than heat absorption peak of femoral cartilages tissue of healthy patient. Heat absorbed during denaturation process in all these cases are close to each other with experimental error accuracy and corresponds to 52±2.6, 51±2.6 and 50±2.5 J/g of dried biomass accordingly. Analysis of the published data makes it possible to assert that the dominant heat absorption stage on DSC curves of tested fresh tissues samples is associated with melting of collagen fibers, hence the thermal stability of the collagen fibers in the patient's tissue is reduced relative to norm.

Adverse local tissue reaction after 2 revision hip replacements for ceramic liner fracture: A case report.

INTRODUCTION: In younger patients, ceramic-on-ceramic (CoC) bearing surfaces are usually recommended for total hip replacement (THR) because of their low wear rate and longer expected functional life. Although technical advancements have reduced the risk of ceramic bearings fracture, this complication remains a major concern. CASE DESCRIPTION: We present the case of a 56-year-old patient undergoing 3 revision hip arthroplasties of the right hip due to ceramic liner fractures. Initial THR (2008) was performed with a CoC bearing, followed by liner fracture due to trauma a year later. The acetabular component and liner were replaced, with a minor incongruence between the old head and new insert. The 2nd ceramic insert fractured 3.5 years later, following minor trauma. Upon revision, the bearing surface was changed to metal-on-polyethylene (MoP). The performed retrieval analysis demonstrated stripe and rim wear, and evidence of adhesive wear. The patient was referred to us a month later, with a fistula on the lateral side of the hip, discharging black, petroleum-like liquid. Radiology showed well-fixed implants, no dislocation and no apparent polyethylene wear. Microbiological assessment of the discharge showed no infection. Intraoperatively massive metallosis was noticed, with stable acetabular and femoral components. The metal femoral head was heavily abraded, with almost 1% volumetric wear. Hematoxylin and eosin stained frozen tissue samples showed muscular and adipose tissue necrosis, while polarized light microscopy highlighted metal, polyethylene, and ceramic particles. CONCLUSION: The present case is yet another report showing the adverse outcomes of using MoP bearings for revision after ceramic liner fracture in THR.

Radiographic Hip Anatomy Correlates With Range of Motion and Symptoms in National Hockey League Players.

BACKGROUND: Hip disorders in athletes have been increasingly recognized. PURPOSE: To characterize radiographic hip anatomy for National Hockey League (NHL) players and correlate it with hip range of motion and hip symptoms and/or surgery. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Fifty-nine professional hockey players (118 hips) with 1 NHL organization (mean age, 24.2 years; range, 18-36) prospectively underwent history and physician examination by 2 independent orthopaedic surgeons. Current or previous groin and/or hip pain or surgery was noted. Anteroposterior (AP) pelvis and bilateral Dunn lateral radiographs were obtained for all players with assessment of hip morphology by 2 blinded independent orthopaedic surgeons. RESULTS: Good to very good reliability of radiographic assessments was noted (intraclass correlation coefficients = 0.749-0.958). Sixty-four percent of athletes had a positive crossover sign, while 86% and 60% had a positive posterior wall sign and a prominent ischial spine sign, respectively. Twenty-one percent of hips demonstrated dysplastic acetabular features (lateral center edge angle <25°). Eighty-five percent and 89% of hips demonstrated cam-type morphology based on alpha angle (>50° Dunn lateral) and head-neck offset, respectively. Good to very good reliability was noted for ROM assessments (intraclass correlation coefficient >0.69). Mean hip flexion was 107.4º ± 6.7º, and mean hip internal rotation was 26.1º ± 6.6º. Thirty-one percent of hips had a history of hip-related pain and/or surgery. Higher AP, Dunn lateral, and maximal alpha angles correlated with decreased hip internal rotation ( P = .004). Greater AP alpha angle correlated with decreased hip extension/abduction ( P = .025), and greater Dunn lateral and maximal alpha angle correlated with decreased hip flexion/abduction ( P = .001). A positive posterior wall sign correlated with increased straight hip abduction, while other radiographic acetabular parameters were not predictive of range of motion. Only decreased hip external rotation and total arc of motion correlated with an increased risk for current or prior hip symptoms or surgery ( P < .001). CONCLUSION: Hip anatomy in NHL players is characterized by highly prevalent cam-type morphology (>85%) and acetabular retroversion (>60%). In addition, acetabular dysplasia (21%) was relatively common. Greater cam-type morphology correlated with decreased hip range of motion, and a positive crossover sign correlated with increased hip abduction. Decreased hip external rotation and total arc of motion were predictive of hip-related pain and/or surgery.

The iliotibial tract: imaging, anatomy, injuries, and other pathology.

The iliotibial tract, also known as Maissiat's band or the iliotibial band, and its associated muscles function to extend, abduct, and laterally rotate the hip, as well as aid in the stabilization of the knee. A select group of associated injuries and pathologies of the iliotibial tract are seen as sequela of repetitive stress and direct trauma. This article intends to educate the radiologist, orthopedist, and other clinicians about iliotibial tract anatomy and function and the clinical presentation, pathophysiology, and imaging findings of associated pathologies. Specifically, this article will review proximal iliotibial band syndrome, Morel-Lavallée lesions, external snapping hip syndrome, iliotibial band syndrome and bursitis, traumatic tears, iliotibial insertional tendinosis and peritendonitis, avulsion fractures at Gerdy's tubercle, and Segond fractures. The clinical management of these pathologies will also be discussed in brief.

Chondral Lesions of the Hip.

The treatment of chondral hip injuries is challenging. However, for young patients with hip disorders, orthopedic surgeons now have the opportunity to intervene early in the development of debilitating joint disease. As understanding of the hip joint continues to evolve, more effective treatment strategies are emerging. There are several reportedly successful options for surgical treatment. This article reviews the clinical presentation of chondral injuries and the surgical modalities, arthroscopic and open, available to treat them.

MR arthrography of the hip with and without leg traction: Assessing the diagnostic performance in detection of ligamentum teres lesions with arthroscopic correlation.

OBJECTIVES: To retrospectively assess the diagnostic performance of hip MR arthrography with and without traction in detecting ligamentum teres (LT) lesions with arthroscopic correlation and to evaluate the effect of traction on the imaging appearance of the LT. METHODS: 73 MR arthrograms (73 consecutive patients, mean age, 34.5 years; range, 14-55 years) obtained without and with leg traction (application of 15-23 kg, use of a supporting plate for the contralateral leg) were included. Two blinded readers independently evaluated LT lesions on MR arthrograms on separate occasions: coronal images without traction; coronal images with traction; a multiplanar traction protocol. MR findings were correlated with arthroscopic records. Sensitivity/specificity of traction and non-traction imaging was compared on coronal images with the exact McNemar test. Imaging appearance of the LT with and without traction was assessed in consensus and compared on coronal images using McNemar and McNemar-Bowker tests. (p<0.05, * corrected for type I error). RESULTS: With arthroscopy 29 (40%) LT lesions were identified in 73 patients. Sensitivity was 72%/90% (without traction/with traction; p=0.25*), specificity was 89%/77% (p=0.25*) for reader 1 in assessing coronal images and for reader 2 sensitivity was 59%/86% (p=0.044*) and specificity was 93%/82% (p=0.25*). Alterations in fiber orientation, signal intensity, surface, dimension, fiber continuity after application of traction were observed in 33/73 (45%, p=0.002*), 6/73 (8%, p=0.223), 9/73 (12%, p=0.36*), 6/73 (8%, p=0.031) respectively 9/73 (12%, p=0.003) cases. Traction-related alterations in at least one criterion were observed in 41/73 (56%) cases. CONCLUSION: Application of traction can considerably alter the imaging appearance of the LT and resulted in higher rates of true-positive and false-positive findings compared to conventional MR arthrography.

Usefulness of MR arthrography of the hip with leg traction in the evaluation of ligamentum teres injuries.

PURPOSE: To retrospectively evaluate the diagnostic accuracy of magnetic resonance (MR) arthrography of the hip with leg traction in the evaluation of ligamentum teres lesions and to evaluate whether there is increased articular distraction, possibly indicating secondary instability, in hips with ligamentum teres injuries. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained for this retrospective study. MR arthrograms of the hip with leg traction of 184 consecutive patients, including 108 men (mean age, 32.6 years; range, 19-53 years) and 76 women (mean age, 38.5 years; range, 18-56 years), who underwent hip arthroscopy were assessed for the presence of ligamentum teres lesions. The MR arthrographic findings were independently assessed by two radiologists who were blinded to the arthroscopic results. The inclusion criteria stipulated no previous surgery, arthroscopy within 1 month after MR arthrography, and availability of a detailed surgical report with ligamentum teres findings. The arthroscopy findings served as the reference standard. Sensitivity, specificity, accuracy, and K statistics for interobserver and intraobserver agreement were calculated. RESULTS: At arthroscopy, 32 ligamentum teres injuries were found. The ligamentum teres was normal in 152 (82.6%) patients and had suffered low-grade partial tears in 15 (8.1%) patients, high-grade partial tears in 10 (5.4%) patients, and complete ruptures in 7 (3.8%) patients. MR arthrography with axial traction demonstrated moderate sensitivity and high specificity for both low-grade (62/93%) and high-grade (66/96%) partial tears. Grouping low- and high-grade partial tears increased the diagnostic performance of MR arthrography, yielding a sensitivity of 87% and a specificity of 95%. For complete ligamentum teres tears, MR arthrography with leg traction demonstrated high sensitivity (92%) and specificity (98%). Articular distraction was significantly increased in patients with complete ruptures of the ligamentum teres (p = 0.001). CONCLUSION: MR arthrography with leg traction offers accurate diagnosis of ligamentum teres injuries. Patients with complete tears of the ligamentum teres exhibit increased articular distraction that may indicate secondary hip instability.

Application of the Goutallier/Fuchs Rotator Cuff Classification to the Evaluation of Hip Abductor Tendon Tears and the Clinical Correlation With Outcome After Repair.

PURPOSE: To assess the reliability and reproducibility of the Goutallier/Fuchs classification for the evaluation of abductor tendon tears of the hip, as well as to identify the relation between preoperative tear size, abductor muscle quality, and the success of endoscopic tendon repair. METHODS: This is a retrospective review of 30 consecutive endoscopic abductor tendon repairs performed by a single surgeon over a 2-year period. Preoperative magnetic resonance imaging scans were reviewed, and the muscle was assigned a grade according to the Goutallier/Fuchs classification. Patient-rated outcome scores--visual analog scale score, Hip Outcome Score (HOS), and modified Harris Hip Score (mHHS)--were collected preoperatively and at a minimum of 2 years postoperatively. Intraobserver and interobserver reliability for muscle grading was calculated. Postoperative outcome measures were compared with preoperative tear size, muscle grade, and repair type to assess for correlations. RESULTS: Of the 30 hips included in the study, over 75% were classified as grade 1 (n = 15) or grade 2 (n = 8). The intraobserver reliability and interobserver reliability of the classification system averaged 0.872 and 0.916, respectively. Two patients (grades 3 and 4) had repair failure and underwent muscle transfer. In the remaining 28 hips, improvement was seen in the visual analog scale score (6.0 v 1.7, P < .0001), HOS-Activities of Daily Living subscale score (58.8 v 83.4, P < .0001), HOS-Sport-Specific subscale score (40.0 v 75.0, P < .0001), and mHHS (55.6 points v 81.1 points, P < .0001) postoperatively. Increasing preoperative fatty infiltration and atrophy correlated with increased postoperative pain levels (regression coefficient, 0.93; P < .001) and decreased postoperative HOS-Activities of Daily Living subscale scores (regression coefficient, -3.36; P = .011), HOS-Sport-Specific subscale scores (regression coefficient, -5.63; P = .016), mHHS values (regression coefficient, -3.50; P = .0008), and patient satisfaction (regression coefficient, -1.04; P < .0001). Patient age, tear size, or repair type (double v single row) did not affect postoperative outcomes. CONCLUSIONS: The Goutallier/Fuchs classification system can be reliably and reproducibly applied to the evaluation of abductor tendon tears of the hip and appears to correlate with patient-rated outcomes after repair. Increasing preoperative muscle fatty atrophy correlates with increased patient pain and decreased patient satisfaction and functional outcomes after repair. LEVEL OF EVIDENCE: Level IV, prognostic case series.

Prevalence of the acetabular sublabral sulcus at MR arthrography in patients under 17 years of age: does it exist?

PURPOSE: To retrospectively determine characteristics of contrast-filled acetabular labral clefts in patients under the age of 17 years at MR arthrography (Mra) correlated with arthroscopy, which may impact the thinking regarding the existence of a sublabral sulcus. MATERIALS AND METHODS: After IRB approval, 41 patients under the age of 17 who had MRa were identified. The following observations of contrast-filled clefts were assessed: (1) presence/absence, (2) location, (3) depth, (4) abnormal signal within the labrum and (5) shape (linear, gaping, complex). Fisher's exact and the Wilcoxon matched-pairs signed-rank test were performed. Interreader agreement was calculated with Cohen's k. RESULTS: Reader 1 found clefts in 41 %. Depth was less than half in 6%, more than half in 65% and full thickness in 29%. Shape was linear in 53%, gaping in 18% and complex in 29%. Signal changes occurred in 88%. Reader 2 found clefts in 29%. Depth was less than half in 17%, more than half in 58% and full thickness in 25%. Shape was linear in 50%, gaping in 42% and complex in 17%. Signal changes occurred in 50%. None of the clefts fulfilled the criteria for a sublabral sulcus at MRa and arthroscopy. CONCLUSION: None of the clefts found in our subjects under the age of 17 years met the MRa and arthroscopy criteria for a sublabral sulcus, which supports the theory that such clefts represent labral tears.

Validation of a standardized mapping system of the hip joint for radial MRA sequencing.

OBJECTIVE: Intraarticular gadolinium-enhanced magnetic resonance arthrography (MRA) is commonly applied to characterize morphological disorders of the hip. However, the reproducibility of retrieving anatomic landmarks on MRA scans and their correlation with intraarticular pathologies is unknown. A precise mapping system for the exact localization of hip pathomorphologies with radial MRA sequences is lacking. Therefore, the purpose of the study was the establishment and validation of a reproducible mapping system for radial sequences of hip MRA. MATERIALS AND METHODS: Sixty-nine consecutive intraarticular gadolinium-enhanced hip MRAs were evaluated. Radial sequencing consisted of 14 cuts orientated along the axis of the femoral neck. Three orthopedic surgeons read the radial sequences independently. Each MRI was read twice with a minimum interval of 7 days from the first reading. The intra- and inter-observer reliability of the mapping procedure was determined. RESULTS: A clockwise system for hip MRA was established. The teardrop figure served to determine the 6 o'clock position of the acetabulum; the center of the greater trochanter served to determine the 12 o'clock position of the femoral head-neck junction. The intra- and inter-observer ICCs to retrieve the correct 6/12 o'clock positions were 0.906-0.996 and 0.978-0.988, respectively. CONCLUSIONS: The established mapping system for radial sequences of hip joint MRA is reproducible and easy to perform.

Labral and cartilage abnormalities in young patients with hip pain: accuracy of 3-Tesla indirect MR arthrography.

OBJECTIVE: Assess the diagnostic accuracy of 3-T indirect magnetic resonance arthrography (iMRA) for hip cartilage and labral pathology detection using arthroscopy as the reference standard and compare it to the published performance of direct magnetic resonance arthrography (dMRA). MATERIALS AND METHODS: Between 2009 and 2011, 290 patients suspected of having femoroacetabular impingement underwent iMRA. Our study group consisted of 41 of these patients (17 males, mean age 35 years; 24 females, mean age 33 years) who did not have a prior history of hip surgery and who subsequently underwent arthroscopy. Two experienced musculoskeletal radiologists separately evaluated the randomized and anonymized studies for the presence and quadrant location of labral and cartilage pathology. These recorded data were compared to arthroscopic reports. RESULTS: Forty-one patients had labral pathology, 34 patients had acetabular and 5 patients had femoral cartilage pathology at arthroscopy. Sensitivity, specificity, accuracy, negative- and positive-predictive values for labral lesion detection were respectively 98, 99, 99, 99 and 98 %; for acetabular cartilage lesion detection they were 69, 98, 89, 87 and 95 %; for femoral cartilage lesion detection they were 69, 95, 93 and 39 %. Sensitivities of iMRA by quadrant (anteroinferior, anterosuperior, posteroinferior, posterosuperior) for the labrum were 100.0, 95.0, NA and 85.7 %, for acetabular cartilage were NA, 58.8, NA and 39.5 % and for femoral cartilage were 50.0, 33.3, 75.0 and 75.0 %). NA indicates results not available because of the absence of findings in those quadrants. Specificities of iMRA by quadrant (anteroinferior, anterosuperior, posteroinferior, posterosuperior) for the labrum (95.0, 100.0, 95.1, 67.5 %), acetabular (100.0, 85.7, 92.6, 79.5 %) and femoral cartilage (100.0, 94.7, 96.2, 85.9 %). CONCLUSION: iMRA at 3 T is accurate in detecting labral pathology suggesting that it is a viable alternative to dMRA.