Ulnar Nerve Entrapment

What is ulnar nerve entrapment?

Ulnar nerve entrapment is the most common ulnar nerve problem. Ulnar nerve entrapment occurs when something puts pressure on your ulnar nerve in your elbow or wrist. Nerve entrapment is a type of nerve compression syndrome.

Compression (a pinched nerve) may lead to inflammation causing nerve (neuropathic) pain and neuropathy (nerve damage). In some cases, this may affect your grip strength, making it difficult for you to grasp items.

What is the ulnar nerve?

Your ulnar nerve is a single nerve in a network known as the peripheral nervous system, which carries information to and from your brain by route of your spinal cord.

Your ulnar nerve helps you bend and straighten your pinky and ring fingers so you can grasp items. The nerve also sends sensory information about touch, pain and temperature. If you bump your ulnar nerve in your elbow, you may experience a tingling “funny bone” sensation. Each arm has an ulnar nerve.

What are the types of ulnar nerve entrapment?

Ulnar nerve entrapment can occur at your elbow or wrist. Types include:

• Cubital tunnel syndrome: Pressure or pulling and stretching of your ulnar nerve in your elbow region.
• Guyon’s canal syndrome: Pressure on your ulnar nerve in your wrist region.

How common is ulnar nerve entrapment?

Cubital tunnel syndrome is the second-most common peripheral neuropathy that affects your upper limbs. (Carpal tunnel syndrome, a pinched median nerve in your wrist, is the most common.) Guyon’s canal syndrome is rare.

What causes ulnar nerve entrapment?

Activities that stretch your ulnar nerve at your elbow, or put a lot of pressure on your elbow, can lead to cubital tunnel syndrome. Sleeping with your elbows bent for long periods can cause or worsen symptoms of ulnar nerve entrapment.

Ganglion cysts are noncancerous fluid-filled sacs that form near your wrist joint. These cysts cause up to 40% of Guyon’s canal syndrome. Another 45% of Guyon’s canal syndrome diagnoses occur for no apparent reason (idiopathic). Less commonly, cysts can also cause pressure on the ulnar nerve within your elbow.

Other causes of ulnar nerve entrapment and damage include:

• Accidents and trauma.
• Arthritis.
• Broken bones and bone spurs.
• Complications from surgeries to treat carpal tunnel or shoulder fractures.
• Diabetes.
• Dislocated elbow.
• Pressure from casts or splints or using crutches.
• Tumors or cysts.

What are the risk factors for ulnar nerve entrapment?

Ulnar nerve entrapment affects more men than women. People who do jobs or activities that require a lot of elbow or wrist pressure or stretching are most at risk, such as:

• Baseball players, golfers and tennis players.
• Bicyclists.
• Construction workers.
• People who smoke.
• Typists, writers and others who use a keyboard frequently.
• Weightlifters.

What are the symptoms of ulnar nerve entrapment and damage?

Signs come on gradually and may come and go. Symptoms may get worse at night or when you do activities that stretch or put pressure on your elbow or wrist.

Symptoms of ulnar nerve entrapment and damage include:

• Curving pinky and ring fingers (like a claw).
• Elbow pain (cubital tunnel syndrome) or wrist pain (Guyon’s canal syndrome).
• Numbness and tingling in your pinky and ring fingers.
• Hand weakness that makes it hard to hold onto or pick up items or perform tasks like writing or buttoning a shirt.
• Muscle loss in your ring or pinky fingers (a rare symptom).

What physical exams can diagnose ulnar nerve entrapment?

Your healthcare provider may perform several tests during your physical exam to evaluate your symptoms. These tests seem simple, but they help your healthcare provider assess finger and hand strength. They include:

• Froment’s test: Your health provider observes how you hold a piece of paper between your thumb and index finger. Flexing at the interphalangeal joint at the tip of the thumb may indicate a nerve problem.
• Tinel’s test: Your healthcare provider gently taps your elbow’s funny bone (ulnar nerve). An extreme shock-like sensation in your pinky or ring finger may suggest a nerve problem.
• Wartenberg’s sign: Your healthcare provider watches as you spread your fingers apart and then bring them back together while resting your hand on a flat surface. You may have a nerve problem if you can’t bring your pinky finger in to meet with the others.

What diagnostic tests can detect ulnar nerve entrapment?

These tests can confirm or rule out ulnar nerve entrapment:

• Electromyography (EMG), including nerve conduction studies, measure how well signals travel through nerves to stimulate muscles.
• MRI, neuromuscular ultrasound or X-rays can show signs of nerve compression and help rule out problems like arthritis, ligament injuries and fractures.

What are nonsurgical treatments for ulnar nerve entrapment?

Nonsurgical treatments for ulnar nerve entrapment include:

• Nonsteroidal anti-inflammatory drugs (NSAIDs) to relieve nerve (neuropathic) pain and swelling.
• Physical and occupational therapy to help you improve flexibility and learn to perform tasks in new ways that are less likely to irritate your ulnar nerve. You may learn nerve-gliding exercises to help your ulnar nerve move more smoothly through ulnar tunnels.
• Splints or braces to support your wrist or elbow.

What are surgical treatments for ulnar nerve entrapment?

If nonsurgical treatments don’t help, you may need surgery. Depending on the cause of the nerve entrapment, surgery can:

• “Release” your pinched ulnar nerve at the point of entrapment.
• Remove tumors or cysts.
• Move your ulnar nerve to the front of your bony elbow joint.

How can I prevent ulnar nerve entrapment?

These steps can lower your risk of developing ulnar nerve entrapment, or ease symptoms:

• Extend and stretch your arms throughout the day if you’re involved in activities that keep your elbows bent for an extended time.
• Don’t rest your elbows on an office chair or desk while typing or working on a computer.
• Secure a towel around your straightened arm at night to keep from sleeping on a bent elbow. Or you can wear an elbow brace backward on the elbow joint.

What are the complications of ulnar nerve entrapment?

Ulnar nerve entrapment in your elbow or wrist that’s severe can cause muscle loss in your hand. This damage may be permanent in some cases, which is why it’s important to see your healthcare provider early about symptoms.

What’s the prognosis for people with ulnar nerve entrapments?

About half of all people with ulnar nerve entrapment get symptom relief through nonsurgical means.

When needed, surgery may eliminate nerve pain and other symptoms. But for about 1 in 8 people with cubital tunnel syndrome, symptoms may return if the procedure doesn’t fully treat the underlying cause. There’s also a risk of surgical damage to your median nerve, ulnar artery or ligaments in your elbow or wrist.

When should I call my doctor?

You should call your healthcare provider if you experience:

• Difficulty picking up or holding onto items.
• Elbow or wrist pain.
• Hand or finger numbness or tingling.
• Problems doing daily tasks like buttoning a shirt or holding a pen.

A note from Cleveland Clinic

Ulnar nerve entrapment occurs when something irritates or puts pressure on your ulnar nerve that runs down your arm. Cubital tunnel syndrome affects your ulnar nerve in your elbow. It’s the most common type of ulnar nerve entrapment. Guyon’s canal syndrome, which affects the nerve in your wrist, is a rare peripheral neuropathy. Talk to your healthcare provider if you experience numbness, pain or tingling in your hands or fingers. You can take steps to prevent nerve damage.