Impingement (Acetabular Side)

The clinical outcome of chondrolabral-preserving arthroscopic acetabuloplasty for pincer- or mixed-type femoroacetabular impingement: A systematic review

While preservation and repair of the acetabular labrum are increasingly being recognized as important goals in hip arthroscopy, controversies still exist regarding the clinical outcome of arthroscopic acetabuloplasty with chondrolabral preservation. A systematic review was conducted and implemented by two independent reviewers, who used the MEDLINE/PubMed database and the Cochrane Database of Systematic Reviews for their search. These databases were queried with the terms "arthroscopic acetabuloplasty" and "chondrolabral preservation" and "arthroscopic acetabular recession." From the 55 initial studies the reviewers finally chose and assessed five clinical studies which were eligible to their inclusion-exclusion criteria. The reviewed studies included in total 444 patients, mainly young, between 30 and 40 years old. The follow-up evaluation varied between 24 and 41 months, while all studies utilized at least a 24-month final end-point assessment. All five studies illustrated improved outcome with the use of chondrolabral preservation acetabuloplasty without labral detachment. The rate of complications was very low. The different techniques of arthroscopic acetabuloplasty combined with chondrolabral preservation illustrated encouraging results in patients suffering from pincer-type or mixed-type FAI. However, the available clinical evidence was limited and insufficient to establish any superiority of these techniques over the traditional labral detachment and sequential reattachment. In relation to the optimal treatment of FAI without isolated CAM, further research of higher quality is recommended to be conducted in order to lead to definitive conclusions.

A Contemporary Definition of Hip Dysplasia and Structural Instability: Toward a Comprehensive Classification for Acetabular Dysplasia

Hip dysplasia has long been known to be a risk factor for pain and degenerative changes in the hip joint. The diagnosis of dysplasia has historically been based on assessments of acetabular anatomy on the anteroposterior pelvic radiograph, most commonly the lateral center-edge angle. Recent advances in imaging of the dysplastic hip with computerized tomography scans have demonstrated that hip dysplasia is in fact a 3-dimensional (D) deformity of the acetabulum and that multiple patterns of hip instability exist that may not be completely assessed on 2D imaging. A more thorough understanding of acetabular anatomy permits an evolution away from vague terms such as "borderline dysplasia." A 3D assessment of the acetabulum and the resultant patterns of instability may be more appropriate since this would allow more accurate treatment to correct the structural instability with acetabular reorientation. With this information, we propose a diagnostic framework that groups symptomatic dysplastic hips into one of 3 categories based on the primary direction of instability: (1) anterior, (2) posterior, and (3) global. This framework may aid the clinician in developing a differential diagnosis for the assessment of hip pain and suspected instability, and for planning an appropriate surgical management.

Arthroscopic acetabuloplasty without labral detachment for focal pincer-type impingement: a minimum 2-year follow-up

In order to access and resect the acetabular rim, arthroscopic acetabuloplasty was described with labral detachment. When the chondrolabral junction remains intact, acetabuloplasty and labral refixation can be performed maintaining an unharmed labrum. We aimed to evaluate the outcome of a group of patients treated with arthroscopic acetabuloplasty without labral detachment. During the study period, we retrospectively analysed 44 patients with pincer-type o combined impingement and an intact chondroblabral junction, with an average follow-up of 32 months (range: 27-38). We excluded patients with isolated CAM-type impingement and previous hip pathology. Radiographs were analysed to define impingement and classify grade of osteoarthritis. Clinical evaluation consisted of pre-operative and post-operative modified Harris hip score (mHHS) and WOMAC as well as post-operative visual analogue scale (VAS) of pain and satisfaction. Reoperations were considered surgical failures for purposes of survival analysis. Mean mHHS changed from 51.06 (SD 4.81) pre-operatively to 84.97 (SD 12.79) post-operatively. Pre-operative WOMAC was 29.18 (SD 8) and post-operative, 13.10 (SD 11). Post-operative VAS was 7.5 and 2.27 for satisfaction and pain, respectively. When comparing patients with Tönnis 0 to those with Tönnis 1, the former showed better results regarding post-operative mHHS (89.9 s versus 77.85, P = 0.03), pain VAS (1.5 versus 6.3, P = 0.03) and satisfaction VAS (8.2 versus 6.3, P = 0.01). Survival was 100% at 24 months and 76% at 40 months (95% CI: 35-98%). Arthroscopic acetabuloplasty without labral detachment achieved good clinical outcomes. Slight degenerative changes on radiographs correlated with poorer clinical outcomes.

Coxa profunda in the diagnosis of pincer-type femoroacetabular impingement and its prevalence in asymptomatic subjects

In many papers, the diagnosis of pincer-type femoroacetabular impingement (FAI) is attributed to the presence of coxa profunda. However, little is known about the prevalence of coxa profunda in the general population and its clinical relevance. In order to ascertain its prevalence in asymptomatic subjects and whether it is a reliable indicator of pincer-type FAI, we undertook a cross-sectional study between July and December 2013. A total of 226 subjects (452 hips) were initially screened. According to strict inclusion criteria, 129 asymptomatic patients (257 hips) were included in the study. The coxa profunda sign, the crossover sign, the acetabular index (AI) and lateral centre-edge (LCE) angle were measured on the radiographs. The median age of the patients was 36.5 years (28 to 50) and 138 (53.7%) were women. Coxa profunda was present in 199 hips (77.4%). There was a significantly increased prevalence of coxa profunda in women (p < 0.05) and a significant association between coxa profunda and female gender (p < 0.001) (92% vs 60.5%). The crossover sign was seen in 36 hips (14%), an LCE > 40° in 28 hips (10.9%) and an AI < 0º in 79 hips (30.7%). A total of 221 normal hips (79.2%) (normal considering the crossover) had coxa profunda, a total of 229 normal hips (75.5%) (normal considering the LCE) had coxa profunda and a total of 178 normal hips (75.3%) (normal considering AI) had coxa profunda. When the presence of all radiological signs in the same subject was considered, pincer-type FAI was found in only two hips (one subject). We therefore consider that the coxa profunda sign should not be used as a radiological indicator of pincer-type FAI. We consider profunda to be a benign alteration in the morphology of the hip with low prevalence and a lack of association with other radiological markers of FAI. We suggest that the diagnosis of pincer-type FAI should be based on objective measures, in association with clinical findings.

Circumferential reconstruction of severe acetabular labral damage using hamstring allograft: surgical technique and case series

INTRODUCTION

With excessive acetabular coverage, such as coxa profunda or protrusio, contact between the femoral neck and acetabular rim cause direct damage to the labrochondral junction, and indirect edge loading from a levering effect which may result in hip arthrosis. Arthrosis may be delayed or avoided by addressing the overcoverage and restoring mechanical function of the labrum. We describe four cases of adjunctive complete acetabular labral replacement for circumferential, irreparable labral injury using fresh frozen semitendinous allografts through surgical hip dislocation.

MATERIALS AND METHODS

Over a two-year period four patients (age range: 20 to 47 years) underwent surgical hip dislocation to address femoroacetabular impingement with rim trimming, femoral osteochondroplasty, and labral reconstruction. Pre- and postoperative patient reported outcomes were assessed by Oxford Hip Score (OHS), Hip Outcome Score (HOS), and Global Treatment Outcome (GTO) score. Disease progression was graded using AP pelvic radiographs and arthroMR.

RESULTS

The average LCE correction was 18º (range 7-25º), achieving an average LCE of 33º (range 32-35) postoperatively. Using protected weight bearing all trochanteric osteotomies healed within six weeks after surgery. OA did not progress in any hips. Mean OHS and HOS scores improved 6.3 and 19.8 at one-year follow up. All four patients reported good results according to the GTO. There were two adverse events that resolved and did not affect outcome.

SUMMARY AND CONCLUSIONS

Despite complex deformities and preexisting cartilage and labrum wear in this young cohort, three of four patients reported significant functional improvement after treatment of this rare condition. Preliminary experience with circumferential labral reconstruction using hamstring allografts is promising, although long-term data needs to be established.

Coxa profunda is not a useful radiographic parameter for diagnosing pincer-type femoroacetabular impingement

BACKGROUND

Coxa profunda is commonly viewed as a radiographic parameter that is indicative of pincer-type femoroacetabular impingement, and this finding can impact diagnostic and surgical decision-making. Validation of coxa profunda as a measure of pincer-type femoroacetabular impingement has not been rigorously analyzed. Our hypothesis was that coxa profunda is a very common radiographic finding in females and is not a finding that is specifically associated with pincer-type femoroacetabular impingement.

METHODS

A retrospective review was performed to determine the prevalence of coxa profunda in four groups of hips: those with acetabular dysplasia (fifty-eight hips), femoroacetabular impingement (fifty hips), symptomatic residual Legg-Calvé-Perthes deformities (sixteen hips), and asymptomatic hips (thirty-three). Coxa profunda was present when the floor of the acetabular fossa touched or was medial to the ilioischial line. The association between coxa profunda and hip disorder diagnosis, lateral center-edge angle, acetabular inclination, patient age, and sex was analyzed.

RESULTS

Coxa profunda was seen in 55% of the 157 hips and was slightly less common in the hips with acetabular dysplasia or residual Legg-Calvé-Perthes deformities (41% and 31%, respectively). Coxa profunda was evident in 76% of the thirty-three asymptomatic hips compared with 64% of the fifty hips with femoroacetabular impingement. Coxa profunda was more common in females than males (70% compared with 24%; p < 0.001). Acetabular overcoverage (a lateral center-edge angle of >40° or acetabular inclination of <0°) was seen in only 22% of hips with coxa profunda.

CONCLUSIONS

Coxa profunda should be considered a normal radiographic finding, at least in females. Coxa profunda is a nonspecific radiographic finding, seen in a variety of hip disorders and asymptomatic hips. The presence of coxa profunda is neither necessary nor sufficient to support a diagnosis of pincer-type femoroacetabular impingement.