Doctor examining patient elbow

Cubital tunnel syndrome is caused by a pinched nerve in the elbow. A form of ulnar nerve compression, it happens when the ulnar nerve, which passes through a narrow space in the elbow called the cubital tunnel, gets compressed. 

The ulnar nerve runs from the neck down to the hand and provides feeling to the small finger (a.k.a. pinky) and half of the ring finger. It passes through a narrow space of tissue in the elbow called the cubital tunnel and behind a bony prominence called the medial epicondyle.

The space where the nerve passes behind the medial epicondyle is often referred to as the funny bone, where the ulnar nerve sits close to the skin and causes pain and tingling if it receives a blow.

Cubital Tunnel Syndrome Causes

The ulnar nerve, being as exposed as it is, is especially prone to compression. Leaning on the elbow for a long period of time can directly damage the nerve because it is so close to the skin and is not protected by muscle or other tissue. 

Bending the elbow causes the ulnar nerve to stretch around the medial epicondyle. Leaving the elbow bent for even short periods of time can irritate the nerve and cause symptoms.

Factors that increase the risk of developing cubital tunnel syndrome include: 

  • Prior injury to the elbow
  • Bone spurs or arthritis of the elbow joint
  • Inflammation at the elbow joint

Symptoms of Cubital Tunnel Syndrome

Most of the symptoms of cubital tunnel syndrome are felt in the hand instead of the elbow, although the condition can sometimes cause a dull ache at the elbow joint. Other symptoms include: 

  • Numbness or tingling in the ring or small fingers
  • Decreased forearm and grip strength
  • Muscle atrophy after a long period of compression

Note that muscle atrophy is permanent. Any suspected cubital tunnel syndrome or ulnar nerve entrapment should be seen by a hand specialist shortly after symptom appear to help prevent muscle atrophy.

Cubital Tunnel Syndrome Diagnosis

A hand expert will begin with a medical history and physical exam. The medical history consists of questions about any past trauma or surgery as well as questions about symptoms: how bad they are, when they appeared and others. 

During the physical exam, the doctor will manipulate the elbow, looking for signs of compression. He or she may also manipulate the neck, press on the funny bone or check the patient’s grip strength. 

Imaging studies are of limited use and are only sometimes needed.  If there is a history of elbow trauma or possible elbow arthritis, an X-ray can help.  Nerve conduction studies can help determine where compression is occurring by measuring how long it takes for nerve impulses to travel up and down the nerve. 

Cubital Tunnel Syndrome Treatment

Conservative, nonsurgical treatments are almost always attempted first in cases of cubital tunnel syndrome. Nonoperative cubital tunnel syndrome treatments can include: 

  • Resting the area: Avoid elbow bending and straightening motions and activities. Using an elbow brace or wrapping the arm in a towel can help prevent the elbow from bending while asleep.
  • Corticosteroid injections: These powerful anti-inflammatories can create more room in the cubital tunnel and alleviate nerve compression by eliminating swelling.  These are only sometimes helpful in cubital tunnel syndrome.
  • Nerve gliding exercises: This form of physical therapy can help the ulnar nerve pass more freely through the cubital tunnel and help prevent swelling and stiffness in the elbow joint.

If ulnar nerve compression has gone on for more than a few weeks or conservative treatment has proven ineffective, surgery to relieve pressure on the ulnar nerve may be necessary. Surgical procedures to treat cubital tunnel syndrome include: 

  • Cubital tunnel release: This procedure involves creating more room in the cubital tunnel by dividing the roof of the cubital tunnel.  This decompresses the ulnar nerve and often permanently relieves symptoms and allows the nerve to recover.
  • Ulnar nerve transposition: In some people, the ulnar nerve snaps over the medial epicondyle when the elbow flexes and extends, a condition called ulnar nerve subluxation.  In those cases, after the ulnar nerve is released, it is moved from behind the medial epicondyle to in front of it, so the nerve no longer rubs against it.
  • Medial epicondylectomy: The medial epicondyle is wholly or partially removed so it no longer creates friction on the ulnar nerve. This procedure is rarely needed.


Recovery from cubital tunnel syndrome is generally not long. Patients most often return to light activity within 1-2 weeks and most often resume full activity in 4-6 weeks.

If you are experiencing numbness or tingling in your small finger (pinky) or ring finger and suspect you may have a compressed ulnar nerve, request an appointment with Dr. Jacobson. He can determine the cause of your discomfort and take steps to relieve it.