US 2003/0199876 A1 · Bone fixation assembly

Abstract

The present invention relates to a bone fixation assembly for securing a fixation device, such as a bone plate, to bone. The assembly includes the fixation device, a bushing, a fastening screw, and a locking screw. The bushing is seated within a through hole in the fixation device and can rotate within the through hole and has a sidewall with a bore. The sidewall has at least one slot for allowing outward expansion of the sidewall against the through hole to thereby lock the bushing at a selected angle relative to the axis of the through hole. The fastening screw has a threaded shaft for insertion through the bore of the bushing and threads into bone to secure the bushing and fixation device to bone. The head of the fastening screw fits in the bushing and includes a radial wall and open end defining a recess. The radial side wall has at least one slit for allowing outward expansion of the radial wall thereby outwardly expanding the sidewall of the bushing. The locking screw has a body that threads in the head of the fastening screw to thereby outwardly expand the radial wall of the fastening screw.

Claims20

Dependent claims

A method for preventing fastener backout from a bone plate having a through hole, the method comprising the steps of:

disposing an annular member in the through hole of the bone plate;
disposing a fastener having a head and a shaft through the annular member;
threadably coupling the shaft of the fastener into a bone;
and
after the shaft is threadably coupled to the bone, expanding the head of the fastener against the annular member to resist motion of the head therein.

2 more elements

Dependencies are inferred from the claim text.

Bone fixation assembly

Life of this patent

Bone fixation assembly

Life of this patent

Abstract

Claims20