What is the main difference between total and partial hip replacement?

Pelvic component: Total hip replacement involves a metal stem with a ball on the end placed in the thigh bone and a fixed metal cup placed in the pelvis. The ball can rotate in the cup. Partial hip replacement uses a larger ball that rotates in the natural socket. Partial hip replacement in usually done for a fractured hip.

Components: In a total, the cartilage is removed and a metal /plastic socket is placed in the pelvis . A stem is placed in the thigh bone. Both are intended to be solidly fixed in the bone. In a partial hip, only the stem is placed in the thigh bone and a large head (ball) is placed on the stem and sits inside and moves around in the pelvis socket, which still has its native cartilage.