Anchor-in-anchor system

摘要

An anchor-in-anchor fixation system is provided for securing underlying structure, such as bone. The fixation system includes a linkage that defines first and second bores, a first bone anchor having a shaft for fixation to underlying bone, and a head that is configured to attach to the linkage in the first bore, and a second bone anchor having a shaft for fixation to underlying bone and a head that is configured to attach to the linkage in the second bore.

主权项

1. A linkage configured for use in an anchor-in-anchor system, the linkage comprising:
a linkage body defining an open upper end, a lower end, and at least one side having a threaded outer surface and an inner surface opposite the threaded outer surface, wherein the inner surface defines an internal void that extends between the upper and lower ends, the upper and lower ends spaced from each other along a central linkage axis of the linkage body; wherein 1) the lower end of the linkage body defines a first bore that is open to the internal void, the first bore extending along a central axis, the lower end internally threaded so as to purchase with complementary threads of a first head of a first bone anchor and attach the first bone anchor to the linkage, and 2) the linkage body includes an interior surface that defines a second bore that extends through the linkage body along a central axis that is oblique to the central linkage axis, the interior surface threaded so as to purchase with complementary threads of a second head of a second bone anchor so as to attach the second bone anchor to the linkage.