Medical instruments for use in spinal surgery, namely, trocars, spacers, cannulas, inserters, mechanical levers, curettes, dilators, retractors, and separators; spinal implant systems, namely inter-vertebral body implants, inter-vertebral disc prostheses, pedicle screws, spacers, stabilizing cords, plates, measuring gauges, spinal implant positioners, and expanders; spacer positioning devices, namely surgical grippers and measuring gauges; spinal implant placement devices, namely trocars, cannulas, and inserters; spinal implant tools; extension limiting devices, namely spacers and inter-spinous implants comprising artificial material; spinal fusion devices, namely, rods, screws, expandable screws, plates, fusion cages, and cervical plates; dynamic spinal stabilization devices, namely artificial discs and inter-spinous implants comprising artificial material; inter-spinous process devices, namely spacers, inter-spinous implants comprising artificial material; and spinal deformity corrective devices, namely rods, screws, plates, fusion cages, spacers, inter-spinous implants comprising artificial material, artificial discs, artificial vertebral bodies, surgical mesh, and inter-vertebral disc prostheses