HUGH D. HESTAD,JACK A. DANT,ERIC J. LUNDEQUAM,ERIC P. JERKE,DEBORAH L. HOCH
申请号：
US14164797
公开号：
US20140142640A1
申请日:
2014.01.27
申请国别(地区):
US
年份:
2014
代理人:
摘要：
A polyaxial bone anchor including a housing and a bone screw. A bottom surface of the housing includes an aperture that defines an angulation limit of the bone screw for each azimuthal angle around a longitudinal axis of the housing. The aperture is V-shaped, with the V-shape having converging side walls that define a low-angulation direction near their intersection and a high-angulation direction opposite the low-angulation direction. In some cases, the angulation limit of the bone screw is generally constant over a range of azimuthal angles centered around the high-angulation direction. The housing may be modular, including tabs on one component that are plastically deformed to engage a lip on another component. During assembly, a mandrel advances longitudinally along a bore in the housing, and forces the tabs radially outward toward the lip to a radially outward plastically deformed state.
