Abstract: A lag screw member and a compression screw for maintaining a broken bone fragment fixed adjacent the principal bone and for applying compression force between the fragment and the principal bone. The lag screw member includes a first end with cutting threads for anchoring the lag screw member within the principal bone. The other end of the lag screw member includes a threaded socket for receiving the threaded portion of the compression screw after it passes through the bone fragment. The broad slotted head of the compression screw holds the bone fragment under pressure against the principal bone when the compression screw is rotated into the socket of the lag screw member.

Abstract: An implantable prosthetic joint, particularly suitable for use as an elbow joint, comprising a first component and a second component, each of which includes a stem implantable in bone. The first component has a head portion whose end is essentially spheroid, the head portion being slotted and having a transverse bore therethrough. The second component has a head-engaging portion including a protuberant disc-shaped portion received in the slot of the head portion of the first component. A transverse bore in the protuberant portion is aligned with the bore in the head portion of the first component, and a pin assembly is positioned within the bores for hingedly attaching the first and second components. The head-engaging portion of the second component includes overlying shoulders which receive the ball-shaped head portion of the first component on either side of the slot.