Bone screw systems with pressure caps having biasing members

摘要

A spinal fixation system comprising a bone screw, a body, and a pressure cap. The bone screw may comprise a head at a proximal end and a bone connection element at a distal end. The body may comprise a proximal end, a distal end, a mounting rod receiving channel at the proximal end and a bone screw head receiving channel at the distal end. A proximal end of the pressure cap may comprise two side walls disposed apart from each other and one biasing member on each side wall. A distal end of the pressure cap may comprise a surface operable to contact at least a portion of the head of the bone screw. The pressure cap may be operable to exert pressure on the bone screw when a mounting rod is biased against the proximal end of the pressure cap.

主权项

1. A spinal fixation system, comprising:
at least one bone screw comprising:
a head at a proximal end; anda bone connection element at a distal end; at least one body comprising:
a proximal end;a distal end;a mounting rod receiving channel disposed at the proximal end of the body; anda bone screw head receiving channel disposed at the distal end of the body;wherein the proximal end and distal end are disposed along a longitudinal axis; andwherein a proximal portion of the mounting rod receiving channel comprises an internal thread for receiving a compression element; and at least one pressure cap comprising:
a proximal end comprising:
at least two side walls disposed apart from each other, wherein the at least two side walls define a groove therebetween, a distal end of the groove comprising a curved surface operable to mate with a mounting rod received within the groove, wherein an inner surface of each of the at least two side walls comprises a vertical surface extending proximally from the curved surface; andat least one biasing member disposed on a proximal end of each side wall, such that a portion of the biasing member is suspended freely above a majority of a corresponding side wall to allow the pressure cap to contact the body via the biasing member; anda distal end comprising;
a surface operable to contact at least a portion of the head of the bone screw; wherein the pressure cap is configured to be disposed within the body and between the mounting rod and the bone screw; and wherein when the mounting rod is biased against the proximal end of the pressure cap, the distal end of the pressure cap is operable to exert pressure on the bone screw.