Kienbock's Disease is also known as avascular necrosis of the lunate bone in the wrist. Like most things living in your body, bone requires a blood supply for nutrition. In this condition, the lunate loses its blood supply leading to death of the bone. The lunate is one of eight small bones in the wrist and plays an important role in stabilization and support of the wrist.
Loss of blood supply to the lunate can occur due to multiple factors. It can be caused by injury to the bone after trauma (e.g. a sudden fall onto the wrist or hand) that disrupts that blood supply to the bone. Injury can also occur after repetitive stress placed onto the wrist. Some patients may also variations in pattern of blood supply to the lunate. Sometimes it happens for no definable reason.
Anatomy is an important factor in this disease. In some patients, the ulna bone of the forearm can be shorter than the radius bone of the forearm. Compared to the normal equal length of both bones, the shortened length of the ulna leads to increased contact between the radius and the lunate, therefore placing more stress onto the bone.
Patients may be asymptomatic with this disease and can be found incidentally while being worked up for something else. Those that are symptomatic may complain of pain on the top (i.e. knuckle) side of the wrist. Wrist pain may occur at rest or with movement, particularly extension. Over time, the wrist may stiffen and lose range of motion as well.
Dr. Steven Lee will likely start with an x-ray. Depending on what stage of the disease you are at, and possibly to rule out other diagnoses, Dr. Lee may order other imaging studies such as an MRI or CAT Scan (CT). Blood tests may also be ordered.
The treatment of Kienbock's disease depends on the stage, disease severity, and what symptoms or functional deficits the patient is experiencing. In early stages without much symptoms, Dr. Lee may ask that you wear a wrist immobilizer for up to 4-6 weeks. If left untreated, the lunate bone can lose its normal shape and eventually fall, leading to accelerated arthritis of the wrist.
If symptoms progress, surgical options may be discussed. The type of surgery chosen depends significantly on the stage of the disease, but also how symptomatic and/or functionally disabled the patient has become. Dr. Lee will make every attempt to save the lunate bone, especially in the earlier stages. This might entail leveling out or reshaping the Radius and Ulna bone if there is a discrepancy. Or, if there is no discrepancy, and the overall structural integrity of the bone is intact, new bone can be transferred over to replace the dead portions of the lunate bone. This is called a Vascularized Bone Graft.
Sometimes the lunate bone has been destroyed and just cannot be saved. Secondary arthritic changes at the wrist have furthermore normally occurred. In this case, some sort of salvage type procedure will likely be employed. Again, several different procedures are utilized depending on what we have to work with. See the SLAC wrist section for a more extensive description of surgeries designed to help this problem.
Dr. Steven Lee has a special interest in the surgical treatment of Kienbock's disease, and especially in the treatment of SLAC wrist. He has been performing research on this subject for the last 7-8 years. Please feel free to ask Dr. Lee about his specific expertise on this problem.
The post-operative protocol will depend on the type of treatment rendered. In general, a splint will be placed immediately after surgery and sutures will be removed usually between 1-2 weeks after surgery. It is important to keep the hand up and elevated above the heart level and your dressings clean and dry as much as possible for the first week.
After a varying amount of splint time, patients will usually benefit from hand/physical therapy, which can last for up to 2-3 months. Patients can expect to steadily improve for up to one year after surgery.
*It is important to note that all of the information above is not specific to anyone and is subject to change based on many different factors including but not limited to individual patient, diagnosis, and treatment specific variables. It is provided as an educational service and is not intended to serve as medical advice. Anyone seeking specific orthopedic advice or assistance should consult Dr. Steven Lee or an orthopedic specialist of your choice.
*Dr. Steven Lee is a board certified orthopedic surgeon and is double fellowship trained in the areas of Hand and Upper Extremity Surgery, and Sports Medicine. He has offices in New York City, Scarsdale, and Westbury Long Island.