Abstract: A total hip joint prosthesis with primary fixation includes a partially threaded elongated pin for insertion into the femoral body to provide primary support for the prosthesis. Attachable thereto is a proximal body whose shape simulates the proximal medial region on the femur and provides a neck for the attachment of a head to contact the acetabulum. The components are constructed to allow for relative rotational adjustment between the body and the pin, thus providing for various alignments and size combinations to offer a custom fit in view of the individual patient's needs. A tapered bore through the body member receives a threaded mounting post on the pin while a nut having a tapered bottom portion seats within the bore to secure the components in a fixed manner.