Introduction and Objective. To estimate the prevalence of acetabular ossifications in the adult population with asymptomatic, morphologically normal hips at CT and to determine whether the presence of labral ossifications is associated with patient-related (sex, age, BMI), or hip-related parameters (joint space width, and cam- and pincer-type femoroacetabular impingement morphotype). Materials and Methods. We prospectively included all patients undergoing thoracoabdominal CT over a 3-month period. After exclusion of patients with a clinical history of hip pathology and/or with signs of osteoarthritis on CT, we included a total of 150 hips from 75 patients. We analyzed the presence and the size of labral ossifications around the acetabular rim. The relationships between the size of labral ossifications and patient- and hip-related parameters were tested using multiple regression analysis. Results. The prevalence of labral ossifications in this population of asymptomatic, non-OA hips was 96% (95%CI=[80.1; 100.0]). The presence of labral ossifications and their size were correlated between right and left hips (Spearman coefficient=0.64 (95%CI=[0.46; 0.79]), p<0.05)). The size of labral ossifications was significantly associated with age (p<0.0001) but not with BMI (p=0.35), gender (p=0.05), joint space width (p≥0.53 for all locations) or any of the qualitative or quantitative parameters associated with femoroacetabular morphotype (all p≥0.34). Conclusions. Labral ossifications are extremely common in asymptomatic, non-osteoarthritic hips. Their size is not correlated with any patient-, or hip-related parameters except for the age. These findings suggest that the diagnosis of osteoarthritis or femoroacetabular impingement morphotype should not be made based on the sole presence of acetabular labral ossifications

Objectives. The aim of this study was to systematically review the literature on measurement of muscle strength in patients with femoroacetabular impingement (FAI) and other pathologies and to suggest guidelines to standardise protocols for future research in the field. Methods. The Cochrane and PubMed libraries were searched for any publications using the terms ‘hip’, ‘muscle’, ‘strength’, and ‘measurement’ in the ‘Title, Abstract, Keywords’ field. A further search was performed using the terms ‘femoroacetabular’ or ‘impingement’. The search was limited to recent literature only. Results. A total of 29 articles were reviewed to obtain information on a number of variables. These comprised the type of device used for measurement, rater standardisation, the type of movements tested, body positioning and comparative studies of muscle strength in FAI versus normal controls. The studies found that hip muscle strength is lower in patients with FAI; this is also true for the asymptomatic hip in patients with FAI. Conclusions. Current literature on this subject is limited and examines multiple variables. Our recommendations for achieving reproducible results include stabilising the patient, measuring isometric movements and maximising standardisation by using a single tester and familiarising the participants with the protocol. Further work must be done to demonstrate the reliability of any new testing method. Cite this article: E. Mayne, A. Memarzadeh, P. Raut, A. Arora, V. Khanduja. Measuring hip muscle strength in patients with femoroacetabular impingement and other hip pathologies: A systematic review. Bone Joint Res 2017;6:66–72. DOI: 10.1302/2046-3758.61.BJR-2016-0081

In order to evaluate the relationship between acetabular and proximal femoral alignment in the initiation and evolution of osteoarthritis of the dysplastic hip, the acetabular and femoral angles were calculated geometrically from radiographs of 62 patients with pre-arthrosis and early osteoarthritis. The sum of the lateral opening angle of the acetabulum and the neck-shaft angle was defined as the lateral instability index (LII), and the sum of the anterior opening angle of the acetabulum and the anteversion angle of the femoral neck as the anterior instability index (AII). These two indices were compared in dysplastic and unaffected hips. A total of 22 unilateral hips with pre-arthrosis were followed for at least 15 years to determine whether the two indices were associated with the progression of osteoarthritis.

The LII of the affected hips (197.4 (sd 6.0)) was significantly greater than that of the unaffected hips (1830 (sd 6.9)). A follow-up study of 22 hips with pre-arthrosis showed that only the LII was associated with progression of the disease, and an LII of 196 was the threshold value for this progression.