Ulnar tunnel syndrome

What is ulnar tunnel syndrome?

It is a pathology that results from the compression or irritation of the ulnar nerve at the elbow. The ulnar nerve is one of the three main nerves of the arm, originating from the neck extending to the hand; it can be compressed along its path, especially near the clavicle or in the wrist. The most frequent site of compression is behind the inside of the elbow, constituting the ulnar tunnel syndrome.

Risk factors for developing the condition include: previous fractures or elbow dislocations, bone spurs or arthrosis, elbow edema, elbow cysts, or repetitive or prolonged activities that require elbow maintenance in flexion. Sometimes it happens in people who spend long periods with elbows in flexion (eg, during sleep, spending a lot of time on the phone or driving) or who spend a lot of time leaning on their elbows.


What are the symptoms?

Patients may complain of medial pain of the elbow, however the symptoms are more frequent in the hand and fingers - ring and pinky, sometimes an electric shock sensation. These symptoms are usually intermittent and sometimes wake the patient at night. Weakness in grip and difficulty in finger coordination (such as typing or playing an instrument) can occur and usually occur in the most severe cases of nerve compression.

In situations of compression and prolonged suffering of the nerve, muscular atrophy of the hand may occur, which is not reversible. For this reason, it is important to consult the orthopedist if the symptoms are severe and have been present for more than six months.


How is it diagnosed?

The diagnosis is usually clinical, based on the description of the symptoms by the patient, on the observation and objective examination performed by the physician. Radiographic examinations may be useful to evaluate the presence of bony prominences, or nerve conduction studies that test the ability to send nerve messages as if they were "electric cables"; during these examinations, small needles are placed on some muscles that are innervated by the ulnar nerve to check for nerve conduction.


Can the treatment be non-surgical?

In most cases, when there is still no muscle atrophy, the symptoms can be controlled with conservative treatment, based on the modification of activities (avoiding prolonged and repeated elbow flexion) and orthoses. Non-steroidal anti-inflammatory drugs (such as ibuprofen or others) may be prescribed to decrease local edema. In some cases, physical therapy may be helpful.


What is the surgical treatment?

Surgery is indicated in three situations:


  1. Non-surgical methods were ineffective in improving symptoms
  2. The ulnar nerve is very compressed
  3. Nerve compression caused muscle weakness or injury


Surgical treatment relies on nerve release, cutting the "roof" of the tunnel, reducing pressure on the nerve. Some authors suggest transposition of the nerve to anterior location, in addition to its simple release, in order to reduce relapses, although it is a more complex approach and prevents future arthroscopy (for example). In some cases partial medial epicondilectomy, ie, excision of part of the medial epicondyle, may be necessary.

Surgical results are best when compression is mild to moderate. As the nerve recovers slowly, it can take considerable time to recover.


How do the postoperative recovery process?

Depending on the surgery, the patient may need to wear a splint for a few weeks and the patient may be referred for rehabilitation.