Apparatus for posterior stabilization of thoracolumbar spine, has abrasion resistant material layer provided in clamping area of clamping screw and carbon-composite rod

摘要

The apparatus comprises a polyaxial or mono-axial screw (5) inserted into a vertebral pedicle, where the screw is made of titanium. A clamping screw (7) is provided at a head unit (6), which is fixed by clamping an inserted carbon-composite rod (2). An abrasion resistant material layer (1) is provided in the clamping area (3) of the clamping screw and the carbon-composite rod. The abrasion resistant material layer is made of titanium, titanium alloys, titanium-aluminum alloys, stainless steel, tantalum, tantalum alloys, silicon and plastic, particularly polyethylene.