Asymmetric epiphyseal closure of the femoral head as a potential cause of the primary cam lesion: a case report.

Cam-type femoroacetabular impingement is a pathologic condition caused by repetitive impact of the abnormal femur on a normal acetabular rim, resulting in damage to the articular cartilage. Excluding cases with known underlying diseases, the development of primary cam deformity is not well understood. Here, we describe a patient with cam-type femoroacetabular impingement exhibiting delayed epiphyseal closure at the site of the cam lesion. The authors believe that this may represent a cause of primary cam deformity, and hereby report the case with review of the literature.