Abstract: A fastener adapted to expand into bone has a tubular body having a longitudinal opening therethrough with a stop within the opening. The body has a head at one end and a longitudinal slot extends through the body near the other end to form ribs that expand radially when the body is compressed. A puller projects through the opening in the rivet and has a head that engages the other end to compress the rivet when the puller is pulled through the body. An annular recess is formed in the puller near the head and the other end of the body is crimped into the recess to aid expansion of the ribs. The puller is weakened at a point so that it will break upon continued pulling after the ribs reach a fully expanded state.

Abstract: An expandable rivet assembly for attaching objects, especially when using bone. The assembly includes a rivet and puller where the puller is pulled to expand the rivet. A stop is provided in the rivet to set an upper limit to the expansion of the rivet by the puller. This rivet is useful in material of varying density, and has slots on the side and a contoured surface to initiate bending at a desired location.