Patent ID: 8333807

Claim:
A modular femoral hip implant trialing system comprising: a trial proximal body including a neck having a head engagement trunnion and a proximal surface, the trial proximal body defining a proximal bore, a tapered distal bore adapted to receive a trial distal stem, and a passageway connecting the proximal bore to the distal bore, the proximal bore is axially aligned with the distal bore along a first axis; a fastener having a head in the proximal bore and a stem in the distal bore; a spring-type Belleville washer between the head and a base of the proximal bore; and a fastener retention member in the proximal bore, the retention member and the washer are on opposite sides of the head, the retention member includes an aperture having a diameter smaller than a diameter of the head to retain the fastener within the proximal bore, wherein the proximal body further defines a slot extending through the proximal bore along a second axis that is transverse to the first axis, the fastener retention member is seated within the slot, wherein the stem of the fastener is threaded and the fastener is movable to a first position in which the fastener cooperates with a threaded receptacle of a distal stem to retain the distal stem in the tapered distal bore such that the distal stem is free to rotate within the tapered distal bore during trialing; and wherein the fastener is movable to a second position in which the fastener extends further within the threaded receptacle than in the first position to retain the distal stem within the tapered distal bore to form a taper lock between the proximal body and the tapered distal bore.