SPINAL STAPLE
A bone anchor assembly includes a bone fixation member and a bone screw. The bone fixation member includes at least one opening therethrough for receiving the bone screw. Two pairs of legs extend from a plate portion of the bone fixation member and are configured for insertion into bone. A lip of the opening is configured for engaging a set of threads on the bone screw such that the bone screw and the bone fixation member are affixed to one another once the bone screw is inserted through the opening of the plate portion. An installation tool for inserting the bone fixation member into bone includes a proximal region, a tubular member, a rotatable collar, and a gripping mechanism.
1 . An anchor assembly comprising:
a bone fixation member having a plate portion including,
an opening having a lip,
a first pair of legs disposed at a first end thereof, and
a second pair of legs disposed at a second end thereof, wherein each leg includes a distal tip configured for penetration into bone; and
a screw having a head and a shank extending therefrom, the shank having threads formed on an outer surface thereof, wherein engagement between the threads of the screw and the lip of the opening deform the lip thereby affixing the screw to the bone fixation member.
2 . The anchor assembly of claim 1 , wherein the screw includes a U-shaped channel for receiving a rod.
3 . The anchor assembly of claim 1 , wherein the screw includes threads for engaging a set screw.
4 . The anchor assembly of claim 1 , wherein the screw includes a coupling and a collet such that relative movement between the coupling and the collet releasably retain a rod with the screw.
5 . The anchor assembly of claim 1 , wherein the plate portion is formed from a first material and the screw is formed from a second material that is harder than the first material.
6 . The anchor assembly of claim 5 , wherein the plate portion is formed from titanium.
7 . The anchor assembly of claim 5 , wherein the screw is formed from a titanium alloy.
8 . The anchor assembly of claim 1 , wherein the bone fixation member is releasably attachable to an installation tool.
9 . The anchor assembly of claim 1 , wherein the bone fixation member includes a plurality of openings.