What Is Ulnar Nerve Entrapment?

Ulnar nerve entrapment, or cubital tunnel syndrome, occurs when the nerve in your elbow becomes compressed and causes numbness, pain, tingling, or weakness. This condition can affect your hand, elbow, forearm, and fingers.

Signs & Symptoms

If you develop ulna nerve entrapment, you may experience a sensation similar to hitting the funny bone in your elbow. The ulna nerve, also called the “funny bone” nerve, follows a groove on the inner side of your elbow.

Other common cubital tunnel syndrome symptoms:

• Hand pain—It is common to experience pain and tingling in your hand, ring finger, and small fingers.
• Numb hand—Your hand may also feel numb, especially if your elbow is bent for an extended period. Many people experience this symptom at night after their elbow is bent for a long time while sleeping.
• Weakened grip—Your grip and arm muscles may feel weaker.
• Elbow pain—You might notice a throbbing pain on the inside of your elbow.

Bilateral tunnel syndrome is entrapment of the ulnar nerve in both elbows, causing symptoms in both hands.

Causes

There are several underlying causes of cubital tunnel syndrome. The exact cause of your condition may remain unknown.

Cubital tunnel syndrome causes:

• Repetitive motions—Repeatedly bending your elbow can cause cubital tunnel syndrome. This can occur when you reach, pull, lift, or lean on your elbow for a long time.
• Injuries—Damage to your ulnar nerve can cause cubital tunnel syndrome. This may include a traumatic injury, such as a fall or car accident.
• Pre-existing conditions—Previous injuries, bone spurs, or arthritis in the elbow can lead to cubital tunnel syndrome.

Risk Factors

Certain factors place you at higher risk of cubital tunnel syndrome.

Risk factors include:

• Intense Activity—If you participate in sports, hobbies, or work that involves repetitive use of your elbow, you are at increased risk for cubital tunnel syndrome.
• Gender—More men than women develop the condition.
• Cysts—Fluid-filled sacs that grow around the elbow can precipitate ulnar nerve entrapment.
• Previous Injuries—Damage, dislocation, or fracture to your elbow can lead to the condition.
• Other Conditions—Arthritis, bone spurs, and diabetes can increase your risk of developing cubital tunnel syndrome.

Diagnosis

A diagnosis for cubital tunnel syndrome usually follows a general examination, review of your medical history, and a series of diagnostic tests.

Diagnostic tests:

• X-Ray—Your doctor may order an x-ray to rule out other causes of your symptoms. Your doctor will look for bones spurs or arthritis affecting your elbow.
• Electromyogram (EMG)—This test measures the electrical activity in your muscles. An EMG can help your doctor determine if the compression of your ulnar nerve is causing muscle weakness or numbness.
• Nerve conduction test—This test measures the speed of electrical impulses as they travel along your nerves. It can help your doctor determine if the compression of your ulnar nerve is causing pain, weakness, numbness, or tingling.

Treatment

Cubital tunnel syndrome is treated with non-surgical or surgical procedures. Surgery is often reserved for individuals who do not respond to other, less invasive options.

Non-Surgical Treatment

Non-surgical cubital tunnel treatment is more common than surgical treatment.

Non-surgical options:

• Avoidance—Avoiding pressure on your elbow can help reduce your symptoms.
• Bracing or Splinting—You may need to wear a brace or splint to keep your elbow in a locked position while you sleep.
• Padding—Wearing a pad to protect your elbow can help you avoid pain and injury.
• Medicine—Anti-inflammatory medicine can reduce pain and swelling.
• Nerve Gliding—Your doctor may perform a simple manual technique to realign your ulnar nerve. A physical therapist may teach you how to perform this simple stretch exercise for yourself at home. This is a form of cubital tunnel syndrome physical therapy.

Surgical Treatment

The goal of cubital tunnel surgery is to relieve pressure on the ulnar nerve.

Surgeries may include:

• Decompression—Decompression of the ulnar nerve involves removing any bones or tissues that are putting pressure on your nerve.
• Trimming—This surgery involves trimming the bump on the inside of your elbow. The ulnar nerve passes under this bump. Trimming the bump removes some of the pressure on your nerve.
• Nerve Transposition—Your doctor might transfer the ulnar nerve to the front of your elbow where it is not aggravated.
• Nerve Layering—Your doctor might also move the nerve under a layer of muscle or fat. This releases pressure on the nerve.

Prevention

You can take steps to prevent cubital tunnel syndrome. Prevention involves protecting your elbow and limiting excessive movements.

Prevention activities:

• Wear protective padding on your elbows.
• Keep your elbow in a straight position.
• Avoid excessive repetitive motions.
• Warm up before intense activity.
• Stretch during breaks in physical activity.
• Avoid resting your elbow on hard surfaces.