Ulnar Impaction Syndrome
Why does it occur?
The ulna is one of the two bones of the forearm that forms a joint with both the elbow and the wrist, the other being the Radius. Ulnar impaction Syndrome refers to the ulna bone being too long relative to the radius bone (ulna positive variance), causing the ulna to pinch or impact on the wrist bones as well as the cartilage in between called the (TFCC)
Why would the Ulna bone be longer than the Radius bone?
A history of a distal radius fracture can be another cause of ulnar impaction should a patient's radius bone heal “short”. A shortened radius bone causes a relative increase in a patient's ulnar variance. Some people are just born with an ulna that is too long.
Patients most commonly present with ulnar-sided wrist pain (pain on the pinky side of the wrist) that is worse with wrist extension (motion simulating a push up), or twisting of the forearm. Pain may be sudden with trauma, or have a gradual onset that may be precipitated by overuse or trauma. Eventually the pain can be constant and not activity related.
X-rays are usually performed to assess your wrist joint, specifically to assess for ulnar positive variance. An MRI may be considered to assess the TFCC as well as the other ligaments in the wrist.
Nonoperative treatment is usually initial management, with splinting and activity modification being the mainstays. If the pain is mild, Dr. Lee will discuss splinting options and activity modifications to help rest the joint and allow your pain and swelling to come down. Avoiding weight bearing activities (i.e. push-ups) on the wrist may also help. Cortisone injections can temporarily alleviate pain and swelling, yet are not a permanent solution given the underlying cause is an anatomic abnormality. Cutting edge nonoperative care such as PRP may also be utilized.
Certain TFCC tears can often heal on their own when immobilized in a wrist splint for at least 4 weeks. It is important to consistently wear the splint and to take it off only to wash, but to wear it otherwise at all other times including sleeping. Also, while wearing the splint, patients should also refrain from rotating/twisting their forearm, and otherwise letting pain be their guide to avoiding other activities. Some TFCC tears may not heal even if properly immobilized. Injections such as PRP to increase the body's own healing potential, or corticosteroid injections to decrease the amount of inflammation may also be used as part of the non-operative treatment plan.
Surgery is usually considered in patients who have failed nonoperative management. The ulna can often be shortened via a minimally invasive wrist arthroscopy (scope) procedure called the Wafer procedure. The wafer procedure is usually reserved for those with ulnar positive variance < 3-4mm. Patients with ulnar positive variance >3mm will usually undergo a more involved ulna shortening procedure utilizing plates and screws. In certain severe cases, especially in those associated with inflammatory disorders such as Rheumatoid Arthritis, the end of the ulna bone may be removed.
Having been fellowship trained in both Hand and Upper Extremity as well as Sports Medicine, Dr. Steven J. Lee is exceptionally well-versed in wrist arthroscopy and other minimally invasive techniques, and regularly instructs other surgeons in labs on how to perform these procedures
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Patients undergoing the Wafer Procedure will be placed into a removable wrist splint at their first post-op appointment. Patients will need to wear the splint over the next 4-6 weeks. Patients will start therapy once cleared to remove the splint. Therapy is an extremely important part of the recovery and normally lasts 6-12 weeks. Total recovery time is usually 3-4 months.
Patients undergoing a formal ulna shortening with plates and screws will be placed into a long-arm (i.e. above the elbow) cast at their first post-operative appointment. This cast is typically worn for 3-4 weeks, after which patients are placed into a removable wrist splint. Therapy typically begins about 6 weeks after surgery and is an extremely important part of the post-op recovery process. Total recovery time is usually 3-4 months.
Immediate Post-Operative Instructions
Please refer to the following pages for more information:
*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.