MODEL RELEASED. Carpal tunnel syndrome surgery. Image 10 of 13. Surgeon performing surgery on a tendon in the wrist of a carpal tunnel syndrome (CTS) patient during surgery. As the original tendon has been damaged, a tendon from another part of the body is being spliced into the wrist. The joint has been pinned to restrict movement and ease pain. CTS is a condition caused by the compression of the median nerve in the wrist. The cause is not known, although repetitive movements and stress are often blamed. Sometimes it can be treated with steroids or physiotherapy, but in severe cases the wrist is immobilised surgically with metal pins. For a sequence of images showing this surgical procedure, see M551/437-M551/449.