This has a separate epiphysis, and the epiphysial line practically-but not absolutely-corresponds with the edge of the articular surface. A prolongation of the cartilage-covered surface on to the front of the neck is frequently found : this underlies the Ilio-psoas tendon.

The head forms about two-thirds of a sphere, and is larger in male than in female bones. The position and size of the fovea varies : one or two small foramina sometimes seen in it are for vessels derived from the obturator artery. The synovial funnel that surrounds them is attached to the depressed margin of the fovea and is lost outside this on the cartilage.