A compression transmission collar apparatus for implantation into a bone with a hole having a hole wall comprising an intramedullary nail defining a bore and a threaded fastener and a compression transmission collar including an exterior face and a top edge and a bottom edge and a first end interstcting the top edge at an acute angle and the bottom edge at an obtuse angle and a second end intersecting the top edge at an obtuse angle and the bottom edge at an acute angle and the first end partially overlapping and opposing the second end to define a slit such that applying a compressional load to the top edge causes the first end to slide relative to and along the second end causing the compression transmission collar to compress axially and expand radially pressing the exterior face against the hole wall.
US 8,317,789 B2
LeCronier, David and Atkinson, Patrick, "Compression Transmission Collar for Fastening" (2012). Mechanical Engineering Patents. 22.