Hip replacement surgery, also called total hip arthroplasty,
involves removing a diseased hip joint and replacing it with an
artificial joint, called a prosthesis. Hip prostheses consist of
a ball component, made of metal or ceramic, and a socket, which
has an insert or liner made of plastic, ceramic or metal. The
implants used in hip replacement are biocompatible — meaning
they're designed to be accepted by your body — and they're made
to resist corrosion, degradation and wear.  Hip replacement is
typically used for people with hip joint damage from arthritis
or an injury. Followed by rehabilitation, hip replacement can
relieve pain and restore range of motion and function of your
hip joint.  Apr. 19, 2011