3-dimensional acetabular morphology of Chinese population

Abstract

INTRODUCTION: The ethnic difference in hip pathology may suggest distinct anatomy of the Asian hips. We studied the 3-dimensional (3D) acetabular morphology in Chinese population, which would provide useful information on the aetiology of hip arthritis and the design of total hip arthroplasty (THA) prostheses. METHODS: Volumetric computed tomography pelvis data of 94 subjects (188 hips) without hip symptoms were utilised for 3D construction. The acetabular parameters, including acetabular anteversion angle (AVA), acetabular abduction angle (ABA), acetabular depth (AcD), acetabular width (AcW), depth-to-width ratio (AcD/AcW), acetabular diameter (AcDi), and anteroposterior acetabular arc angle (AAA) were measured and calculated on each subject. RESULTS: There were 54 female and 40 male subjects. Their mean age was 31.6 years. Their mean (± standard deviation) AVA, ABA, AcD, AcW, AcD/AcW, AcDi, and AAA were 20.8° ± 6.2°, 39.3° ± 13.1°, 18.4 ± 2.0 mm, 46.0 ± 3.0 mm, 40.0 ± 4.0, 47.5 ± 3.5 mm, 154.1° ± 11.2° in females, and 17.8° ± 6.0°, 42.7° ± 17.6°, 20.2 ± 2.1 mm, 51.1 ± 3.1 mm, 39.5 ± 4.0, 52.9 ± 3.8 mm, 153.1° ± 11.2° in males. Female acetabula were significantly more anteverted (p<0.05) and smaller than males. When compared with the Caucasian data, Chinese acetabula were smaller and shallower. DISCUSSION AND CONCLUSION: A shallow acetabulum may be the cause of low incidence of pincer-type femoroacetabular impingement and primary osteoarthritis. It may also call for the need of special Asian prostheses in THA.