Bone plate system

摘要

A bone plate system having a retainer for resisting back-out of a bone anchor from a throughbore of a bone plate is provided. In one aspect, a bone plate system having a resilient retainer disposed in a bone plate throughbore with a pair of elongate arm portions of the resilient retainer extending along opposite sides of the throughbore. In another aspect, a bone plate system having a resilient retainer with a pair of elongate interference portions completely exposed in the throughbore and spaced from each other across the throughbore to retain a head of a bone anchor received in the throughbore. In addition, a bone plate system having a resilient retainer with a pair of opposite end portions disposed within a groove of a throughbore wall such that a bone anchor may be inserted into the throughbore without contacting either of the opposite end portions of the retainer.

主权项

1. A bone plate system comprising:
an elongate bone plate having a longitudinal axis; a throughbore of the bone plate having a predetermined axial length along the bone plate axis with the throughbore having a pair of opposite axial end portions along the axial length of the throughbore; a bone anchor; an enlarged head of the bone anchor for being received in the throughbore; a resilient retainer disposed in the throughbore; a pair of elongate arm portions of the resilient retainer extending along opposite sides of the throughbore; interference portions of the elongate arm portions disposed in the throughbore to be adjacent or in a predetermined one of the axial end portions of the throughbore; bone plate engaging portions of the resilient retainer at the other axial end portion of the throughbore with the other axial end portion of the throughbore and the bone anchor head being configured and sized relative to each other to allow the bone anchor to extend obliquely in the throughbore with a raised portion of the bone anchor head generally level with the retainer bone plate engaging portions at the other axial end portion of the throughbore and a lowered portion of the bone anchor head disposed below the retainer interference portions in the throughbore so that the retainer interference portions are in interference with the bone anchor head lowered portion to resist back-out of the bone anchor from the throughbore; and the retainer interference portions and bone anchor head are configured so that with the interference portions extending above the lowered portion of the bone anchor head no portion of the bone anchor head extends over the interference portions.