Polyaxial plate rod system and surgical procedure

摘要

A spinal fixation device includes a bone screw, a nut, a bearing, a slider, and a plate construct. The screw has a head with a nut connection and a screw portion. The nut has an exterior wall and a bore connecting to the nut connection. The bearing has an exterior and defines a bore fitting therein the nut connection and the exterior wall of the nut. The slider defines a bore fitting the nut exterior wall therewithin and has an exterior with a given shape. The elongate plate construct has a first end defining a first opening shaped to accept the exterior of the bearing therein and a second end defining a second opening shaped to accept the slider therein and having a corresponding shape to the given shape to permit the slider to slide in at least a portion of the second opening.

主权项

1. A spinal fixation device, comprising:
at least one bone screw having:
a screw portion shaped to screw into bone; anda head with a nut connection section having:
exterior threads; andan expanded section between the exterior threads and the screw portion and wider in diameter than the exterior threads and the screw portion and having an upper chamfered surface tapering inwards and upwards from a larger outer diameter to a smaller inner diameter; at least one locking nut having:
a nut internal bore shaped to connect to the nut connection section of the at least one bone screw;an exterior wall having a given outer diameter;interior threads shaped to mate with the exterior threads of the nut connection section;a head with a head diameter greater than the given outer diameter;a lower lip with a lip diameter greater than the given outer diameter; anda lower-facing, chamfered surface tapering from the head at the head diameter to the exterior wall at the given outer diameter, the exterior wall being disposed between the lower lip and the upper chamfered surface; a bearing:
having a spherically shaped exterior; anddefining a bearing internal bore shaped to fit therein:
the nut connection section of the head; andthe exterior wall of the at least one locking nut, the bearing internal bore having an upper surface, an intermediate surface, and a lower surface; at least one slider:
defining a slider internal bore shaped to fit the exterior wall of the at least one locking nut therewithin; andhaving an exterior with a given shape; and an elongate plate construct having:
a first end defining a first opening shaped to accept the exterior of the bearing therein; anda second end defining a second opening shaped to accept the at least one slider therein and having a corresponding shape to the given shape to permit the at least one slider to slide in at least a portion of the second opening.