An ulnar shortening osteotomy is sometimes considered in patients with persistent ulnar sided wrist pain.
The joint surfaces at the end of the radius and ulna normally sit at an equal level. However, there is significant variation between people, and some patients may have an ulna which is longer than the radius whilst others may have an ulna that is shorter.
Patients with an ulna that is longer than the radius are referred to as having a positive ulnar variance. Patients may have up to 4mm of positive variance and still be considered within normal anatomical variation ranges.
With a longer ulna, patients will have more load-bearing on that side of the wrist. In cases of pain due to irritation of the ulnar sided structures, a shortening of the ulna may be appropriate.
This operation involves removing a thin slice of the ulna and therefore shortening the overall length.
Procedure
The procedure is performed under a general anaesthetic in theatre. A tourniquet is used to prevent any bleeding. An incision is made directly over the ulna and the bone is exposed. A dedicated plate is used to help with the fixation and accurate cutting guides are used to remove the precise length of bone that is required.
The wounds are sutured and local anaesthetic is injected for post-operative pain relief. A plaster of paris splint is applied to keep the arm still and comfortable.
Most patients remain in hospital overnight with the arm elevated to reduce swelling. Patients are reviewed again two weeks later for removal of the sutures – in most cases they can start some gentle mobilisation of the wrist and forearm at that stage. Usually the osteotomy site will show signs of healing on x-ray at six weeks.