Cubital Tunnel Syndrome

What is cubital tunnel syndrome?

ulnar nerve entrapment at the elbow (cubital tunnel syndrome)
Reproduced with permission from OrthoInfo. © American Academy of Orthopaedic Surgeons.

Cubital tunnel syndrome is the compression of the ulnar nerve in the cubital tunnel, which is a passageway for the ulnar nerve right behind the bony bump on the inside of the elbow. The ulnar nerve, located near the skin’s surface and commonly referred to as the “funny bone,” can become pinched or trapped due to physical abnormalities in this channel, such as increased pressure from the bone or connective tissue.

Cubital tunnel syndrome is the second most common compression neuropathy in the upper extremities (after carpal tunnel syndrome). Frequently asked questions about cubital tunnel syndrome and how it is treated are answered in the video and information below:

What are the symptoms of cubital tunnel syndrome?

Compression of the ulnar nerve results in loss of blood flow to the nerve, which causes tingling or numbness in the ring and small fingers of the affected arm. Other symptoms can include weakness or atrophy of the muscles in the hand. Patients with cubital tunnel syndrome often report difficulty grasping or holding onto certain objects without dropping them. There can also be pain in the cubital tunnel region of the elbow and inner forearm.

Symptoms may be worse, or present in episodes, when leaning on the elbows – particularly on hard surfaces – and when bending the elbows for sustained periods of time (for example, when talking on the phone). Night episodes of numbness are common because it is natural to sleep with your elbows bent, which puts pressure on the nerve. In more advanced cases, numbness can become constant and a claw-like deformity may appear in the hand.

What causes cubital tunnel syndrome?

Most cases of cubital tunnel syndrome are idiopathic, meaning there is no specific identifiable cause. Its occurrence becomes more common as people age, and for those with diabetes and hypothyroidism. Other causes can include:

  • Trauma
    • Direct impact or chronic pressure on the inner aspect of the elbow can cause swelling and the eventual formation of scar tissue around the ulnar nerve; or
    • Injury to the bones of the elbow joint can cause changes in the alignment of the joint placing tension on the ulnar nerve.
  • Instability: Loss of stability of the fascial tissue that encloses the nerve can cause the nerve to become damaged as it slides in and out of its normal position.
  • Arthritis: Elbow arthritis can produce swelling of the joint, narrowing the cubital tunnel.

What are the treatment options for cubital tunnel syndrome?

Non-surgical treatment options include rest and splint, which are more helpful for patients with mild symptoms. Resting the hand and arm helps avoid activities that may provoke further symptoms, and the use of a splint at night to prevent flexion may improve or relieve symptoms.

Surgical treatment is called Cubital Tunnel Release, which involves ulnar nerve decompression, and for some, transposition. Both procedures involve opening the roof of the cubital tunnel overlying the ulnar nerve, but for those who need it, transposition includes an added step of repositioning the nerve from behind the bony bump on the inside of the elbow to the front of the elbow.

When is ulnar nerve decompression appropriate?

For anyone with cubital tunnel syndrome, ulnar nerve decompression is appropriate when non-surgical treatment has not relieved intermittent symptoms, or when symptoms progress to constant numbness or an abnormal feeling in one or more fingers at all times.

When is ulnar nerve transposition appropriate?

The need for a transposition of the ulnar nerve is determined during surgery. Once the nerve has been decompressed, the elbow is taken through a range of motion. If the nerve remains stable behind the bony bump, then transposition is not necessary. However, if the nerve is unstable after taking the pressure off the nerve, then a transposition is an appropriate course of action.

How are these procedures performed?

A 3-inch incision is made along the course of the ulnar nerve, and the roof of the tunnel is opened, thus relieving the pressure on the nerve. Then, if it is determined that ulnar nerve transposition is needed, the surgeon will reposition the nerve from behind the bony bump on the inside of the elbow to the front of the elbow (if a transposition is required, the incision will be enlarged). In both cases (decompression with or without transposition), the incision is closed using dissolvable sutures, and the arm is placed in a long-arm bulky dressing, to be worn for 10-14 days after surgery.

How long will it take to recover from cubital tunnel release surgery?

  • Recovery time varies by individual; it can take up to 2-3 months before achieving full, unrestricted use of the extremity.
  • Early motion is allowed, but no lifting, pushing or pulling any objects greater than a pencil for six weeks after surgery.
  • Physical therapy is sometimes needed and typically starts six weeks after surgery.

Will cubital tunnel release surgery relieve my symptoms?

The answer depends on the severity of damage to the ulnar nerve prior to the surgery:

  • For patients who only experience intermittent episodes of numbness, damage to the nerve is not likely and the numbness episodes will usually resolve.
  • For patients with constant numbness, the relief of symptoms will depend on the patient. Most will notice improvement, and for some it will resolve completely. Other patients will not recover normal sensation due to nerve damage. Improvements may occur for up to 12-18 months after surgery. And, while full sensation may not return, the surgery can prevent symptoms from getting worse.

For more information about what to expect before, during and after cubital tunnel release surgery, click the button below:

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