Abstract: Disclosed is a reconfigurable hip joint prosthesis and elements therefor which is adapted to be surgically implantable in a human body, a part in the upper femur, another part in the pelvis. The implantable prosthesis may be configured in a reversible manner, and provide alternative configurations as may be desired or necessary. The present invention also includes a method of implanting into a human body a prosthesis as described herein, and subsequently reconfiguring the prosthesis as may be desired or necessary. A still further aspect of the invention is a kit of component parts used in providing a configured implantable prosthesis.