A small, threaded, implantable rod with a screw head and drive intended for internal spinal fixation by being screwed into the spine to hold a correction/stabilization device (e.g., rod, plate, tether) to bone; it is made of a material that is not chemically degraded or absorbed via natural body processes (e.g., surgical steel, titanium alloy, carbon fibre). It is available in various types (e.g., pedicle or transfacet, with a slotted, cross, star, or polygonal drive), and is typically used to provide immobilization and stabilization of spinal segments in the treatment of spinal instabilities or deformities. A screw head adaptor intended to stabilize a rod may be included with the screw.
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