Radial Tunnel Syndrome

What is Radial Tunnel Syndrome?

Radial tunnel syndrome is a painful condition caused by pressure on the radial nerve of the forearm. The entrapment or compression occurs frequently in the proximal forearm in the radial tunnel; a narrow space formed by muscles, bone, and tendon near the elbow joint.

The radial nerve emerges from the C5-C8 and T1 spinal nerves. It is one of the three major nerves of the hand that supplies the hand muscles helping in movement and sensation of the hand and wrist.

Symptoms 

Symptoms include a dull aching pain at the back of your hand, outside of the elbow or on top of the forearm. Pain worsens when you straighten your arm or finger. You may also experience weakness of your hand and wrist and decreased the ability to grip objects. Untreated radial tunnel syndrome may lead to permanent nerve damage.

Causes

Compression of the radial nerve can be caused by:

• Bone tumours
• Trauma to the nerve
• Repetitive or overuse injuries
• Inflammation of surrounding tissue
• Health conditions such as thyroid problems and diabetes

Diagnosis

• Your doctor will review your medical history and perform a thorough physical examination of your elbow.
• Electrodiagnostic tests such as electromyography and nerve conduction studies may be used in determining how well the nerve is functioning and locate areas of muscle wasting and nerve compression.
• You may be asked to move your middle finger against resistance. Pain while performing this movement indicates radial tunnel syndrome.
• Imaging studies such as X-ray or MRI confirms the diagnosis.

Treatment

Non-surgical Treatment

Your treatment plan may include the following options:

• Using prescribed non-steroidal anti-inflammatory drugs (NSAIDs) and opioids to manage pain and inflammation.
• Applying ice packs over a towel to the injury to help reduce swelling and pain.
• Avoid pressure on the nerve by not leaning on the elbow. Pads may be worn to decrease pressure when working at a desk.
• Wearing a brace or splint at night while sleeping to keep the elbow in a straight position may be recommended. You can also wrap the arm loosely with a towel and apply tape to hold it in place.
• Avoid activities that tend to bring on the symptoms.
• Steroid injections may be administered to reduce pain and inflammation.
• Occupational therapy may be recommended for improving flexibility, range of motion and strength-building.

Surgery

Surgery may be recommended if you do not respond to non-surgical treatment options. The goal of the surgery is to reduce the pressure on the radial nerve by providing more space for the nerve to move freely and to increase blood flow for the nerve to heal.

The most common surgery is the radial tunnel release procedure that is performed under local anaesthesia. The muscles causing compression are identified and slightly incised to create more space for the nerve. A bulky dressing with a plaster splint is usually applied following surgery for 10-14 days. Elbow immobilisation for 3 weeks after surgery or longer is usually indicated, depending on the repair performed. Occupational therapy will be ordered a few weeks after surgery to maximise the use of the hand and forearm.