Ligament of the head of the femur in the orangutan and Indian elephant.

A literature search revealed that for over 100 years there has been a consensus that the ligament of the head of the femur (LHF) is absent in the orangutan and elephant. A dissection of the hip joints of an adult orangutan and an adult Indian elephant exposed, in each joint, a robust LHF that is functionally important. These LHFs are easily overlooked during a cursory examination of the hip joints because of the way they differ from the human LHF