Ulnar Nerve Decompression

Introduction

The ulnar nerve is one of the main nerves in the arm that travels down from the neck behind a bony protuberance inside the elbow (medial epicondyle), under the muscles of the forearm and down the hand on the side of the palm, towards the little finger. The ulnar nerve helps in controlling most of the hand muscles which carry out fine movements as well as some bigger forearm muscles which help in making a strong grip.

The ulnar nerve can be constricted at many places, which results in nerve entrapment. The compression pressure on the nerve can cause pain and numbness in various parts of the arm. Compression of the nerve occurs most commonly against the medial epicondyle and is called cubital tunnel syndrome. Ulnar nerve release or transposition are surgical procedures performed to release the pressure over the ulnar nerve and transpose or move the ulnar nerve to another position from the back of the medial epicondyle.

Indications

Ulnar nerve decompression or transposition is indicated to relieve the pressure placed on the compressed ulnar nerve. Conditions that may require ulnar nerve transposition include:

  • Compression of the ulnar nerve caused due to injury or excessive pressure placed on the elbow
  • Ulnar nerve entrapment due to cubital tunnel syndrome
  • Snapping of the ulnar nerve over the medial epicondyle
  • Failure of non-surgical treatment
  • Drawing back (clawing) of the fourth and fifth digits of your hand
  • Progressive loss of the hand’s ability to move

Surgical Procedure

Ulnar nerve decompression and transposition are performed under general or regional anesthesia.

Incision and nerve location: Your surgeon will make a small incision around the medial epicondyle and locate the ulnar nerve.

Decompression: Your surgeon will release the tight tissue overlying the ulnar nerve.

Transposition: Your surgeon may move the ulnar nerve from behind the medial epicondyle and positions it in front of it (anterior transposition). The nerve can be placed on top of the muscle, under the skin and fat (subcutaneous transposition), under the muscle (sub muscular transposition) or within the muscle (intramuscular transposition). The incision will then be sutured. The anterior transposition prevents nerve entrapment at the bony ridge and stretching of the nerve when the elbow is bent.

Post-Operative care

Following the procedure, the elbow is placed in a sling. Home exercises are initiated for range of motion and light strengthening. Return to full activities is usually 5-6 months after surgery.

Risks and Complications

As with any surgical procedure, ulnar nerve transposition involves certain risks and complications. Some of the complications that may occur include:

  • Nerve injury
  • Failure to completely decompress the ulnar nerve
  • Infection