Total hip joint replacement (THR) has been very successful mainly due to the introduction of bone cement for the fixation by Dr. John Charnley on the advice of Dr. Dennis Smith in the late 1950s [Charnley, 1970; Charnley, 1972; Charnley and Cupic, 1973; Eftekhar, 1978; Wroblewski, 1986]. One of the inherent problems of orthopedic joint prosthesis implantation is the fixation and maintenance of a stable interface between the device and the host tissue at the cellular and organ levels [Crowninshield, 1988; Ducheyne, 1988; Park, 1992; Park, 1995]. The fixation can be classified into several categories as given in Table 10.1. Basically, the hip joint can be considered as three parts: (1)

acetabular cup

, (2)

cup-femoral head-articulating surface

, and (3)

femoral stem

(Fig. 10.1). The problems and possible solutions related to each of the three parts will be examined.