Wrist arthritis is very common. There are a number of reasons that wrist arthritis occurs: from scaphoid fractures, ligament injuries, distal radius fractures, metabolic diseases (such as gout), rheumatoid arthritis or from just plain old wear and tear. Wrist arthritis leads to pain, stiffness and often swelling of the wrist.
Regardless of why the wrist arthritis occurred, non-operative treatment should usually be tried first. Non-operative treatment consists of splinting, a steroid injection, and decreasing activities to within the limits of pain. Non-steroidal anti-inflammatory medications, such as Ibuprofen or Naprosyn can also be tried.
If these fail, surgical treatment can be extremely effective. Most cases of wrist arthritis can be treated by a ‘Partial Wrist Fusion’. Partial Wrist Fusions fuse one of the two wrist joints, leaving the other, uninjured joint available for motion. Bone graft (healthy bone that helps the joint fuse) is taken from the distal radius, the large bone of the wrist, through the same incision. Taking this bone graft does not add any pain or down-time to the procedure.
Which Partial Wrist Fusion is best for a particular patient depends upon where the arthritis is. Most commonly, the best option involves excising the scaphoid bone (which is usually involved in the arthritis) and performing a “Mid-Carpal Fusion”. I published a paper in 2003 analyzing Midcarpal Partial Wrist Fusions. The conclusion was that wrist motion is improved by always excising the scaphoid, regardless of whether or not the scaphoid was involved with arthritis.1
Traditionally, the Midcarpal Fusion was a “Four Corner Fusion”, which involves removing the scaphoid and then fusing the four remaining wrist bones, usually with 2 screws. Bone graft from the distal radius is used to facilitate healing. After surgery, the wrist is casted for 6 weeks and then hand therapy is started.
More recently, the Luno-Capitate Fusion, an outpatient procedure that only fuses two bones, the lunate and capitate, has become popular. I prefer this technique as it is less surgery, less painful, heals quicker, and has a lower complication rate. The scaphoid is still excised and distal radius bone graft is still used. If the triquetrum (a wrist bone next to the lunate) has arthritis on it or the Luno-Triquetral Ligament is torn, the triquetrum is also excised. Some pioneering surgeons routinely excise the triquetrum, as this increases motion. The lunate and capitate are stabilized using two staples. Following surgery, the wrist is usually only casted for 3-4 weeks and then therapy is started.
The success rate for Midcarpal Fusions is very high, and the complication rate is low. How much motion the wrist has after surgery depends on how much motion the wrist has before surgery. Classically, if motion is near normal, up to roughly 50% of motion is retained. If motion is poor before surgery, which is usually the case with arthritis, the amount of motion loss is often less. More modern surgical techniques that allow for earlier motion may lead to better motion following surgery. In addition, the Partial Wrist Fusion provides pain relief, strength and stability, and the amount of motion retained is usually very functional.
The Luno-Capitate Fusion is an easy surgery to recommend, as most patients do extremely well and return to work, sports and the other activities that they enjoy, without the pain that used to limit them.
1) Management of the Scaphoid During Four Corner Fusion – A Cadaveric Study, Kobza PE, Budoff JE, Yeh ML, Luo ZP, The Journal of Hand Surgery, Vol 28A:904-9, 2003
Figure: Healed Luno-Capitate Fusion