Devices and methods for dynamic fixation of skeletal structure

摘要

The disclosed screw assemblies include a screw that attaches onto the bone, a housing member that connects and inter-locks the bone screw to the rod, and one or more looking members that permit immobilization of various components of the assembly relative to one another while still permitting some relative movement. The bone screws and bone screw assemblies described herein permit flexible stabilization of the spine.

主权项

1. A bone fixation assembly, comprising:
an interconnecting member; a bone fastener comprising a head segment and a shank configured to extend therefrom, said head segment configured to couple to a first segment of a driver, said driver configured to advance said bone fastener onto a bone; a first housing comprising:
a top surface, an opposing bottom surface, and at least one interconnecting side surface;a first internal bore configured to extend from said top surface to said bottom surface along a first axis; andat least a seat configured to receive at least a portion of said head segment of said bone fastener; a second housing comprising:
a top surface, an opposing bottom surface, and at least two opposing side surfaces configured to connect said top and bottom surfaces;a first bore configured to extend from a first one of said side surfaces to an opposing one of said side surfaces, said first bore sized to seat said interconnecting member; anda second bore configured to extend from said top surface to said bottom surface along a second axis, said second bore sized to permit advancement of said first segment of said driver therethrough; and a locking feature configured to transition from a first state to a second state, said first state configured to enable said second housing to be movable relative to said first housing along a trajectory that is non-parallel to said first axis of said first housing, and said second state configured to rigidly affix said first housing relative to said second housing; and wherein said first housing and said second housing are configured to movably couple and to attain a range of positions relative to one another, at least one of said positions comprising said first axis of said first housing being coaxially aligned with said second axis of said second housing.