Polyaxial bone screw
AssigneeDePuy Synthes Products, Inc.
InventorsDavid D. Konieczynski, Thomas V. Doherty, Dale E. Whipple, Niall Casey, Mark T. Hall
Life of this patent
Estimating the term…
Abstract
The present invention generally provides a polyaxial fixation device having a shank with a spherical head formed on a proximal end thereof, and a receiver member having an axial passage formed therein that is adapted to polyaxially seat the spherical head of the shank. The polyaxial bone screw further includes an engagement member that is adapted to provide sufficient friction between the spherical head and the receiver member to enable the shank to be maintained in a desired angular orientation before locking the spherical head within the receiver member.
Claims10
1-20. (canceled)
A polyaxial fixation device, comprising:
- a receiver member having
- opposed arms that define a rod-receiving recess therebetween,
- a recess formed in a distal end thereof, and
- an annular groove formed in an internal surface thereof;
- a bone screw having a head seated within the recess in the receiver member such that the head is substantially distal to the groove, and a shank extending through an opening formed in a distal end of the receiver member and configured to engage bone;
- and
- an engagement member disposed within the receiver member at a location substantially proximal to the head of the bone screw, the engagement being expandable into the groove, and the engagement member being effective to engage the head of the bone screw to provide sufficient friction between the head and the receiver member to enable the receiver member to be maintained in a desired angular orientation relative to the shank before locking the head within the receiver member.
A method for implanting a polyaxial fixation device, comprising:
- implanting a threaded shank in bone, the shank having a head formed on a proximal end thereof and seated within a cavity in a receiver member such that the receiver member is polyaxially movable relative to the head, the receiver member including an engagement member located substantially proximal to the head, the engagement member being expandable into a groove formed within the receiver member, and the engagement member engaging the head to provide sufficient friction between the head and the receiver member to maintain the receiver member in a desired angular orientation relative to the shank before locking the head within the receiver member.
Dependencies are inferred from the claim text.