Anterior femoroacetabular impingement: part I. Techniques of joint preserving surgery.

The exact pathomechanism responsible for osteoarthritis (OA) of the nondysplastic hip has remained unknown for many years. There is, however, emerging clinical evidence implicating femoroacetabular impingement as an etiologic factor for having early OA of the hip develop. Femoroacetabular impingement is an abutment conflict occurring between the proximal femur and the acetabular rim arising from morphologic abnormalities affecting the acetabulum or the proximal femur, or both. The repetitive mechanical conflict occurring during motion, particularly flexion and internal rotation, can lead to lesions of acetabular labrum and, even more serious, the adjacent acetabular cartilage. Surgical treatment of femoroacetabular impingement focuses on improving the clearance for hip motion and alleviation of femoral abutment against the acetabular rim. We will describe the rationale for the treatment of this condition, and discuss the technique of joint-preserving surgery.