Acetabular retroversion is an accepted cause of Pincer-type femoroacetabular impingement. There is increasing evidence that acetabular retroversion is rather a rotational abnormality of the pelvis than an overgrowth of the acetabular wall or even a dysplasia of the posterior wall. Initially, patients with a retroverted acetabulum were treated with an open rim trimming through a surgical hip dislocation (SHD) based on the early understanding of the pathomorphology. Theoretically, the reduction of the anterior wall can decrease the already small joint contact area in retroverted hips to a critical size. Based on the most recent literature, anteverting periacetabular osteotomy (PAO) seems to be the more appropriate surgical treatment. With this technique, the anterior impingement conflict can be treated efficiently without compromising the joint contact area. However, it is unknown whether this theoretical advantage in turn results in better mid term results of treatment. We asked if anteverting PAO results in better clinical and radiographical mid term results compared to rim trimming through a surgical hip dislocation.Introduction
Objectives
Magnetic resonance imaging with intraarticular contrast (arthro-MRI) and radial cuts is the gold standard to quantify labral and chondral lesions in the setting of femoroacetabular impingement. To date, no study exists that has evaluated these findings as potential predictors of outcome for the long term follow-up after surgical treatment of FAI. The purpose of this study was to detect potential predictors for failure after surgical hip dislocation for FAI based on specific preoperative arthro-MRI of the hip at a minimum follow-up of 10 years.Introduction
Objectives
Labral refixation has established as a standard in open or arthroscopic treatment for femoroacetabular impingement (FAI). The rationale for this refixation is to maintain the important suction seal in the hip. To date, only few short-term results are available which indicate a superior result in FAI hips with labral refixation compared to labral resection. Scientific evidence of a beneficial effect of labral refixation in the long-term follow-up is lacking. Aim of this study was to evaluate if labral refixation can improve the cumulative 10-year survivorship in hips undergoing surgical hip dislocation for FAI compared to labral resection. We performed a retrospective comparative study of 59 patients treated with surgical hip dislocation for symptomatic FAI between December 1998 and January 2003. We analyzed two matched groups: The ‘resection’ group consisted of 25 hips that were treated consistently by excision of the damaged labrum. The ‘refixation’ group consisted of 34 hips that were treated with labral reattachment. Correction of the osseous deformity (rim trimming/femoral osteochondroplasty) did not differ between the two groups. We then evaluated the clinical (Merle d'Aubigné score) and radiographical results (according to Tönnis) at a follow-up of ten years. We calculated a cumulative Kaplan-Meier survivorship curve with the following factors as endpoints: conversion to total hip arthroplasty (THA), radiographic evidence of osteoarthritis progression, or a poor clinical result (defined as Merle d'Aubigné score of less than 15). The two curves were compared using the Log-rank test.Introduction & Objective
Methods
Cam-type femoral acetabular impingement (FAI), is a common structural hip deformity and thought to be a leading cause of early hip osteoarthritis. Although patients who undergo surgical correction notice improved clinical function it is unclear what impact this has on the overall health of the cartilage. T1rho MRI cartilage mapping has been shown to be a reliable imaging technique to assess the proteoglycan (PG) content potentially serving as a biomarker. This study analyses post surgical changes in T1rho levels in hip joints treated with cam FAI. Eleven patients with a mean age of 38 (all males) underwent pre and post T1Rho Cartilage mapping of their hips at a mean time of 20 months post surgical intervention. The acetabulum was spatially divided into 4 main regions of interest (ROI), with levels of T1Rho in cartilage quantified as a whole and in each spatial segment. T1Rho signal is inversely correlated with level of PG content. All patients demonstrated loss of PG content on pre-op imaging with a T1Rho of 33.5ms+2.6ms. Preop T1rho levels were found to significantly correlated with the difference between pre-op and post-op T1rho in entire hip cartilage (R: 0.73; p=0.016). This correlation was reflected both in the anterolateral quadrant (R: 0.86; p=0.002), and in the posteriosuperior quadrant (R:0.70; p=0.035). Additionally, significant correlation was found between improvement of WOMAC pain score over time, and difference of T1rho values over time in the most lateral 3mm slice of the anterolateral quadrant (R: 0.81; p=0.045). Significant correlation was found between pre-op alpha angle at 1:30 and difference between pre-op and post-op total cartilage T1rho content (R: −065;p=0.038). T1Rho Cartilage mapping of the hip is a useful biomarker in the assessment of the surgical management of Cam type FAI. This preliminary data provides some evidence that surgical correction of the deformity can help minimise disease progression.
