Derek S. Lewis,Deepa Mani,David B. Kay,Amanda Martin
申请号:
US12283777
公开号:
US08394132B2
申请日:
2008.09.16
申请国别(地区):
US
年份:
2013
代理人:
摘要:
A cannulated compression screw is used as an orthopedic implant and has a threaded distal end with an insertion tip that includes at least one and preferably two, three or four flutes to allow the screw to be self-tapping. Optionally, the screw also includes one or more reverse cutting flutes proximal to the insertion tip. The distal threads are cancellous threads having a generally constant minor diameter and a generally constant major diameter and a generally constant thread pitch. An intermediate portion of the screw is non-threaded and the proximal end includes a compression wedge or taper that has at least one, and preferably two to five flutes that terminate before the top of the screw. The proximal end further includes a radiused bevel to the terminal surface that includes a hexagonal torque driving recess. The diameter of the non-threaded shaft section is constant distal from the compression wedge to the distal tip where it defines the minor diameter of the threaded portion. The screw optionally includes a tapered insertion tip.