Abstract
The ligament of head of femur in the Asian elephant (Elephas maximus) was examined anatomically and histologically. Collagen fibers formed a thick ligament, which was tightly attached to the acetabular fossa in an area approximately 60 mm long, 20 mm wide, and 10-15 mm deep. The proximal part of the ligament was buried in a deep ditch in the acetabular fossa, and the margin of the lunate surface enveloped the origin ligament. The ligament originated dorso-lateral to the acetabuar center, and ran ventro-medially over the medial surface of the acetabulum along the notch to reach the femoral head. Based on these findings, we advocate a mechanical model in which the thick ligament and its enlarged attachment act to restrict adduction of the femur in this animal, as in humans. Unlike humans, however, we suggest that in the Asian elephant this ligament is not directly involved in restricting extension and flexion.
