Cubital Tunnel Syndrome
What is Cubital Tunnel Syndrome?
Cubital Tunnel Syndrome is a space at the inside of the elbow, Cubital Tunnel, where the ulnar nerve passes alongside the humerus, or funny bone. In fact, the ulnar nerve is actually responsible for the sensation commonly referred to as the funny bone, and not the bone at all. The ulnar nerve is a centrally important nerve to the arm, and provides both use and sensation, so when it is compressed within the Cubital Tunnel, its effectiveness and use can be hampered by this interruption.
What causes Cubital Tunnel Syndrome?
Cubital Tunnel Syndrome can be caused by numerous factors acting on the ability of the ulnar nerve to travel smoothly through it. Unexplained anomalies in the surrounding muscles, tumors and fibrous bands are all known causes of the disorder. Trauma to the elbow or forearm can also cause stretching or traction of the nerve. Commonly, Cubital Tunnel Syndrome is caused by repetitive motion of the elbow, specifically flexion or bending of the elbow, which can irritate the tunnel and cause it to become inflamed and limit the mobility of the nerve by decreasing the space within the tunnel. Repetitive wrist and finger movement on a keyboard can also lead to nerve irritation as well as repeated direct pressure on the elbow on hard desktops while looking at a computer.
Symptoms of Cubital Tunnel Syndrome
Numbness and tingling in the little and ring fingers are also the most common symptoms of Cubital Tunnel Syndrome as the circulation of the nerve is reduced by the compression of the nerve within the tunnel. Cubital Tunnel Syndrome is often indicated by aching pain that originates at the elbow and radiates into the forearm and hand. In advanced cases, weakness is a common symptom, causing difficulty in gripping and grasping and a loss in dexterity. Like other nervous problems of the arm, this pain and numbness can often keep you awake at night, or waken you suddenly in a sharp burst of pain or onset of numbness.
How can I know if I have Cubital Tunnel Syndrome?
As with most problems of the upper extremity, a full history of the injury and a physical examination of the affected area are necessary in order to determine the doctor’s preliminary course of action. The most common and easily performed test is the Tinel’s test, in which your doctor will “thump” his finger over the are of nerve irritation, and if this causes a shockwave of numbness and tingling, he will move forward with treatment. Elbow flexion for 30 seconds reproducing symptoms can also indicate the presence of Cubital Tunnel Syndrome, as it replicates the circumstances under which the issue may arise naturally in your arm over the course of a given day.
Electrodiagnostic testing, in which a small electrode is placed over the nerve and an electric current is run through to determine the conductivity of the nerve, can also be helpful, but is not conclusive, as many people who require surgery still have a negative result in these tests. Finally, X-ray imaging may be used to give the doctor an idea of the osseous elements and bone positions that could lead to Cubital Tunnel Syndrome.
Treatment of Cubital Tunnel Syndrome
Splinting and medication are the only really effective non-surgical treatments for Cubital Tunnel Syndrome, and even then are only effective in patients with mild and intermittent symptoms. NSAIDs to control inflammation will lessen the degree to which the nerve is entrapped in the tunnel. The use of a Pil-O brace when sleeping holding the elbow extended or straight may reduce symptoms or an elbow pad during the day when resting the elbow on hard objects may alleviate direct pressure.
When and if non-surgical attempts to treat Cubital Tunnel Syndrome prove ineffective, surgery is most likely the only option. In this case, there are several possible surgeries that your doctor may suggest, depending on the specifics of your case.
There are several standard procedures that may be done to alleviate the compression. Ulnar nerve decompression with medial epicondylectomy releases the tunnel and then removes part of the funny bone or medial epicondyle. Anterior transposition procedures may also be employed, either with subcutaneous (over the muscle) or submuscular (beneath the muscle) placement of the nerve. When the nerve is transposed care must be taken to move the blood supply with the nerve to keep adequate circulation to the nerve. A submuscular transposition is frequently recommended for elite overhead athletes to put the nerve in a more protective position. Some surgeons perform an endoscopic ulnar nerve decompression procedure, which releases the nerve only. The concern with this procedure is it may not release other sources of compression and the incision is not much smaller than the more traditional procedures.
After surgery, you will be placed in a splint for a length of time determined by your surgery (10 days for the epicondylectomy and up to 3 weeks for the transposition procedures), after which time occupational therapy will be necessary to restore full function.