Ulnar Nerve Entrapment
What is ulnar nerve entrapment?
If you’ve ever hit your ‘funny bone’ on your elbow you’ve hit your ulnar nerve. This long nerve runs from your neck down to your hand and is closest to the skin surface around your elbow. It helps you control your hand and fingers—in particular, your ring and little finger. If you hit your elbow right over the ulnar nerve, you might feel a sharp but temporary tingling in your elbow and in your hand and fingers. This is ulnar nerve pain.
If the ulnar nerve is compressed for an extended time, it can result in a condition called ulnar nerve entrapment, also known as ulnar nerve compression. Continued pressure injures the nerve and damages the muscles it controls. Eventually, ulnar nerve entrapment causes ulnar neuropathy, or entrapment neuropathy. Symptoms include pain and tenderness and progress to hand weakness and loss of function.
The ulnar nerve is long and ulnar nerve entrapment can occur anywhere along your arm, from your wrist to your neck, but the most commonly affected area is the elbow. Entrapment in the elbow is cubital tunnel syndrome. Another common type of ulnar nerve entrapment affects the nerve as it passes through your wrist. This is cyclist’s palsy, affecting many people who put pressure on their wrists, including cyclists and people who use machinery like jackhammers. Ulnar neuropathy is different than carpal tunnel syndrome, which involves the median nerve.
Unless the nerve entrapment is caused by an accident—trauma to the nerve—the symptoms usually develop gradually. Ulnar nerve entrapment treatment can help prevent ulnar neuropathy and disability in the hand. Treatments include lifestyle measures and possibly medicine to relieve inflammation. Surgery may be necessary in some cases to relieve compression.
What are the symptoms of ulnar nerve entrapment?
The most common symptoms of ulnar nerve entrapment affect the hand, below the area where the nerve is compressed. There may be pain at the compression site as well. Ulnar nerve entrapment and neuropathy symptoms usually appear gradually. They may include:
Pain, tingling or numbness in the little finger or half of the ring finger (finger closest to the little finger)
Weakness in the hand
Pain in the area where the nerve is compressed, such as the wrist or elbow
Symptoms worsen when you are cold
Tenderness at the elbow or wrist
If ulnar nerve compression occurs following trauma, the symptoms may appear gradually or immediately, depending on the type of injury.
If you experience any of the symptoms of an ulnar nerve entrapment, see your doctor for an evaluation of your arm. Early treatment of nerve compression may reduce or eliminate symptoms altogether.
What causes ulnar nerve entrapment?
Internal and external forces can cause ulnar nerve entrapment, which stops the nerve’s ability to transmit signals to and from the brain. Internal forces put pressure on the ulnar nerve from inside the arm, such as a broken bone or swelling. External forces are those that exert pressure from outside the arm, such as an object pressing on the area. Some of the most common causes of ulnar nerve compression include:
Repetitive activities, such as playing golf or tennis, which can irritate the ulnar nerve
Leaning on your elbow, often on a desk or an open window in a motor vehicle
Injury to your arm causing pressure on the nerve
Fluid buildup around the nerve
What are the risk factors for ulnar nerve entrapment?
Ulnar nerve entrapment can happen to anyone, but people who lean on their elbows—such as office workers who lean on one elbow at their desk or truck drivers who rest their arms on the open window of their truck as they drive—are at higher risk of developing compression around the nerve. Other risk factors include repeatedly bending and stretching your arm (repetitive motions), keeping your arm out straight for long periods, participating in activities that put stress on your elbow or wrist, and prior fractures to the wrist or elbow.
Reducing your risk of ulnar nerve entrapment
You may be able to lower your risk of developing ulnar nerve entrapment by:
Limiting repetitive stress on the arm
Wearing a protective splint or brace if recommended by your doctor
Avoid leaning on your elbow
Wear a splint at night to keep your arm from bending as you sleep
If you do participate in an activity that increases your risk of developing ulnar nerve entrapment, or you start feeling the first signs of nerve compression, speak with your doctor about care measures to avoid further progression.
How is ulnar nerve entrapment treated?
For the most part, ulnar nerve entrapment treatment is successful without surgery. Once you identify the cause, such as leaning on your elbow or repeated bending and stretching, your doctor may recommend:
Pain medications to reduce inflammation and pain. These may include aspirin or nonsteroidal anti-inflammatories (NSAIDs) such as ibuprofen.
Immobilizing your arm. A brace or splint that keeps your arm from moving will give your arm a chance to heal and prevent you from moving your elbow, especially while you sleep.
Physical therapy or occupational therapy. Hand and arm exercises may help you regain strength in your hand. In some cases, the therapist may recommend nerve-gliding exercises, which encourage the nerves to slide or glide as they should. Heat therapy to heal the tissues may also be effective.
If these treatments do not help ease the ulnar nerve entrapment symptoms, your doctor may recommend ulnar nerve surgery. The procedures for ulnar nerve entrapment treatment include:
Cubital tunnel release surgery. This minor surgical procedure is done on an outpatient basis with local anesthetic to freeze the area around your elbow. An orthopedic surgeon cuts the tissue that is pressing on the nerve. You will need a brace or splint for a few weeks to allow the incision to heal and the inflammation to subside.
Ulnar nerve anterior transposition surgery. For situations where the ulnar nerve is seriously compressed or the nerve has moved out of position, an orthopedic surgeon must relocate the nerve to a less vulnerable position. Although this surgical procedure is more involved than cubital tunnel release surgery, it is also done on an outpatient basis with local anesthetic.
Joint repair: If nerve compression is the result of trauma to the elbow, wrist, or any other area of the arm, an orthopedic surgeon may have to surgically repair the joint and remove tissue or bone parts pressing on the nerve.
What are the potential complications of ulnar nerve entrapment?
Most cases of ulnar nerve entrapment are successfully treated and the symptoms go away. If treatment for ulnar nerve entrapment doesn’t relieve the symptoms, they may become worse with time. If you have surgery, it may take several weeks for you to regain strength and proper feeling in your arm, especially if the condition has been present for a long time. There are potential complications with ulnar nerve surgery, so discuss the benefits and risks of all your treatment options with your doctor.
Ulnar nerve entrapment is often a preventable condition and responds well to treatment in its early stages. Take steps to reduce your risk of developing this type of nerve compression by following good body mechanics (don’t lean on your elbow), avoid repetitive stress, and report any signs or symptoms of ulnar nerve entrapment to your doctor if you notice them.