Ulnar nerve entrapment is an injury to a nerve that runs through the arm into the fingers on the outside of the hand. It commonly occurs at or near the elbow.

While ulnar nerve entrapment is usually not serious, it can have permanent consequences without prompt treatment, including paralysis and loss of feeling in the affected hand or arm.

However, with proper diagnosis and treatment, most people with ulnar nerve entrapment can make a full recovery.

A person stretching to try and prevent ulnar nerve entrapment.Share on Pinterest
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The ulnar nerve, also known as the funny bone nerve, is one of the arm’s major nerves and part of the brachial plexus nerve system. It gets its name from its location near the ulna bone, a bone in the forearm on the side of the pinkie finger.

The ulnar nerve starts in the neck and travels through the shoulder down the arm into the wrist and fingers.

It provides sensation to the forearm and the fourth and fifth fingers. It also innervates or stimulates the flexor muscles of the hand, allowing it to bend and move.

What is ulnar nerve entrapment?

As the ulnar nerve runs the entire length of the arm, there are several places along the nerve that can become compressed or irritated. This compression or irritation is known as ulnar nerve entrapment. Health experts may also refer to it as cubital tunnel syndrome, Guyon’s canal syndrome, bicycler’s neuropathy, handlebar palsy, or tardy ulnar palsy.

Ulnar nerve entrapment is the second most common nerve entrapment after carpal tunnel syndrome. Ulnar nerve entrapment happens most often at or near the elbow, particularly on the inner part of the elbow. Ulnar nerve entrapment can also happen less frequently at or near the wrist.

While these two areas are the most common sites of ulnar nerve entrapment, it can also happen anywhere between the wrist and elbow in the forearm or between the elbow and shoulder in the upper arm.

Following treatment, a doctor may recommend that people perform light exercises to help recovery. A doctor will advise how long and frequently people should perform these exercises. Successfully completing these exercises may mean a person can return to their daily routine within 4 weeks. Exercises may include:

The ulnar nerve runs through the shoulders, elbow, and wrist. Entrapment can occur anywhere along the nerve, but it is most common in areas of the arm that bend. The single most common cause of ulnar nerve entrapment is compression on the ulnar nerve. The compression may be a result of any of the following:

  • leaning on the elbow for an extended period
  • the ulnar nerve slipping out of place when the elbow is bent
  • fluid buildup in the elbow
  • current or previous injury to the inside of the elbow
  • bone spurs in the elbow
  • arthritis in the elbow or wrist
  • swelling in the elbow or wrist joint
  • an activity that causes a person to bend and straighten the elbow joint repeatedly

Treatment for ulnar nerve entrapment depends on how severe the entrapment is.

For less severe cases, a doctor will probably recommend nonsurgical treatment options first. These may include some combination of the following:

  • use of anti-inflammatory medications to reduce swelling
  • elbow braces or splints to keep the joint straight at night
  • exercises and physical therapy to help the nerve slide through the arm correctly

Surgery

If ulnar nerve entrapment is severe or nonsurgical treatment approaches fail, a doctor may recommend surgery to relieve pressure and fix ulnar nerve entrapment.

Surgical treatment options for ulnar nerve entrapment include:

  • Cubital tunnel release: This is a procedure to increase the size of the cubital tunnel to give the nerve more room.
  • Ulnar nerve anterior transposition: A procedure to move the nerve from behind the muscle to in front of it, so there is less tension on the nerve when the elbow is bent.
  • Medial epicondylectomy: A procedure that removes part of the protruding medial bone to prevent the nerve from rubbing on this area.

Doctors will only use these approaches as the first line of treatment if the entrapment is severe enough to cause muscle weakness and wasting.

Surgical recovery varies from person to person and depends largely on the procedure performed. Surgical outcomes for ulnar nerve entrapment are often good, and most people can expect to make a full or nearly full recovery.

Home remedies and prevention

There are lots of things a person who has ulnar nerve entrapment can do at home to promote healing and recovery. These same steps can also prevent ulnar nerve entrapment from recurring or happening in the first place.

A person can help treat or prevent ulnar entrapment at home by doing the following:

  • avoiding any activity that causes the elbow to bend and straighten repeatedly
  • making sure they are sitting at a proper height when using a computer to allow the arm to straighten
  • keeping the elbow straight at night
  • avoiding leaning on the elbow or putting pressure on the inner aspect of the elbow

With active prevention and home treatment, most people can avoid ulnar nerve entrapment.

Some of the symptoms of ulnar nerve entrapment may occur in the elbow, particularly if that is where the problem originates. However, most symptoms of this condition occur in the hand and fingers. Many of the symptoms tend to occur when the elbow is bent.

Symptoms of ulnar nerve entrapment include the following:

  • intermittent pain, numbness, or tingling in the ring and pinkie fingers
  • a weak grip in the affected hand
  • a feeling of the pinkie and ring fingers “falling asleep”
  • difficulty controlling fingers for precise tasks, such as typing or playing an instrument
  • sensitivity to cold temperatures
  • pain or tenderness in the elbow joint, especially along the inner aspect

In severe and long-standing cases, muscle wasting of the hand may also occur.

Proper diagnosis of ulnar nerve entrapment is key to avoiding long-term loss of function and sensation in the affected hand and fingers.

If a person has any of the symptoms of ulnar nerve entrapment for more than a few weeks, they should contact a doctor. Likewise, a person with any severe symptoms of ulnar nerve entrapment should seek medical attention promptly.

Tests

During a checkup for ulnar nerve entrapment, a doctor will begin by asking questions regarding the person’s general health and medical history, including any medications they may be taking. The doctor will then examine the person’s arm and hand.

During the exam, the doctor may bend the person’s elbow or wrist to try to produce symptoms and see whether or not the ulnar nerve slides out of place upon bending the elbow.

The doctor will also check the strength in the hand and fingers and sensation in the hand. Depending on their assessment, the doctor may send a person with ulnar nerve entrapment symptoms for other tests.

This can include X-rays to check the elbow for bone spurs, fractures, or other issues that may cause compression. Additionally, they may perform nerve conduction studies. This involves inserting small needles into the muscles surrounding the ulnar nerve to check muscle function and see how well the ulnar nerve is functioning.

Ulnar nerve entrapment is a common condition that involves the compression of the ulnar nerve. It can occur following stretching, pressure, or injury of the nerve, particularly near the elbow, where the ulnar nerve is most vulnerable.

Symptoms often include pain, tingling, and numbness in the hand, fingers, and elbow. A doctor can use imaging and nerve tests to diagnose the condition and may initially suggest nonsurgical treatments such as braces or splints. In more severe cases, surgery may be necessary to relieve pressure on the nerve.