Operations on bones, joints, ligaments, tendons and the muscular and skeletal structures that support them, including the bony spine. This covers joint replacement and resurfacing for the hip, knee and shoulder, fracture fixation and osteotomy, spine procedures that address the vertebrae and discs such as fusion, laminectomy and discectomy, soft tissue repairs such as rotator cuff repair, ligament reconstruction and tendon transfer, and limb procedures such as amputation, replantation and external fixation. Arthroscopic and open techniques for the same joint are kept in one group rather than split further. Nerve and spinal cord procedures that operate on neural tissue rather than bone, such as rhizotomy or cordotomy, are grouped instead under neurosurgery.