Radial Tunnel Syndrome

The notes on this page are written as a source of information to both patients and health professionals. It is a general overview and its content should not be seen as direct medical advice. Further information regarding diagnosis and treatment specific to your condition can be made via a consultation with Dr Amaranath.

Anatomy of the elbow

The radial tunnel exists as a theoretical space between the level of the radiocapitellar joint (RCJ) and the supinator muscle where the radial nerve (which becomes the posterior interosseous nerve - PIN) passes. Its boundaries consist of the brachioradialis as its roof, biceps and brachialis as its medial border, extensor carpi radialis longus (ECRL) and extensor carpi radialis brevis (ECRB) as its lateral border. Its floor comprises of the radiocapitellar joint proximally and extends distally though the two heads of supinator.

Radial Tunnel Sundrome dr jeevaka amaranath

What is Radial Tunnel Syndrome?

Radial tunnel syndrome (RTS) relates to the compression of the radial nerve within the radial tunnel which leads to sensory symptoms of pain without motor loss. In RTS the pain is commonly felt as a dull ache that is located 5cm distal to the lateral epicondyle.

What are the common causes? 

RTS is commonly caused by compression of the radial nerve at one of the following sites:

  1. Radiocapitellar joint – through presences of fibrous bands, osteophytes, etc

  2. Leash of Henry – Group of vessels related to the radial artery

  3. Extensor Carpi Radialis Brevis – Fibrous edge

  4. Arcade of Frohse – Proximal edge of supinator muscle

Distal edge of supinator muscle

What are the preferred Investigations/Imaging?

  1. Plain X-Ray - This should include an Anterior/Posterior and Lateral. It can rule out any bony causes for the compression.

  2. Nerve Conduction Studies – This has been shown to have variable results and is not as accurate in confirming the diagnosis compared with other neuropathies such as cubital tunnel syndrome.

  3. MRI Elbow – This is useful to rule out any space occupying lesions that may cause compression of the radial nerve.

What are the treatment options?

  1. Non-operative – Once a diagnosis has been obtained initial non-operative measures such as analgesia, corticosteroid injections (this can be diagnostic and therapeutic), physiotherapy and activity modification can be useful 

  2. Radial Tunnel Release – In patients who fail non-operative management, an open radial nerve release would be recommended. This involves an incision over the back of the forearm and releasing the nerve from the leash of henry to the distal edge of supinator.

What does the rehabilitation/recovery involve?

To find out more about rehabilitation and recovery after elbow surgery please see our Rehabilitation Protocols here.