a hip replacement system including a socket having generally hemispherical cavity therein , a ball member cantably affixed within the socket , a stem affixed to the ball member and extending outwardly therefrom , and a lubricant located within a channel formed interior of the stem . the exterior surface of the ball member has at least one opening therein communicating with channel of the stem . the lubricant fills a space between the exterior surface of the ball member and the inner wall of the cavity of the socket . the lubricant is compressed body fat . an inlet is connected to the channel so as to extend outwardly of the stem for allowing the introduction of the lubricant into the channel .