Kienbock’s disease is a condition in which the lunate loses its blood supply and dies, causing pain and stiffness with wrist motion. In the late stages of the disease, the bone collapses, shifting the position of other bones in the wrist. This shifting eventually leads to degenerative changes and osteoarthritis in the joint.
There are several types of surgery that can be done for this problem. Treatment is determined by what stage the disease is in. The goal of treatment is to decrease the load across the lunate and/or bring a better blood supply to it. Milder forms of Kienböck’s can be treated with revascularization (restore blood flow) to the lunate.
During the operation, the surgeon moves a small section of blood vessels (and also possibly bone) from elsewhere in the wrist to the deteriorating lunate bone. Intercarpal fusion fuses the lunate to the carpal bone next to it. It’s not a complete or total fusion because not all of the wrist bones are fused together.
One of the oldest methods for treating Kienbock’s disease is called a lunate excision. The abnormal bone is removed. The empty space left by taking the bone out is filled with a piece of tendon coiled up and stuffed into the hole. An artificial lunate bone may also be used to fill this space and maintain alignment of the bones.
When the lunate has collapsed, but the wrist joint is not terribly arthritic, the four carpal bones of the proximal row may simply be removed. This allows the distal row (the other four bones) to slide down a bit and begin moving against the forearm bones instead. Without the proximal row of bones, the wrist loses its ability to perform complex movements. It becomes more of a hinge joint like the knee.
The advantage is that there is still a good deal of wrist motion. That’s better than having a wrist fusion, which is another surgical option. Proximal row carpectomy is not the first line of treatment for this condition. It’s really considered a salvage procedure. That means it’s a way to save motion at the wrist.
You didn’t mention what type of surgery you are expecting to have. This will determine the amount of motion you will have after the operation. A complete fusion leaves you without wrist motion. It may give you a strong wrist, but it’s very inflexible. A carpectomy provides flexibility but not strength.
Using a hot honey knife requires a stable joint and strength in a motion called ulnar deviation. As you slice down through the comb, grip strength is needed as well as wrist strength on the little finger (ulnar) side of the joint.
Be sure and bring this question up with your surgeon before scheduling the operation. Your occupational requirements are an important part of the decision-making process when trying to figure out which treatment will be best for you.