There are three nerves which supply the arm. Their job is to provide the muscles with instructions to move and to relay sensory information back to the brain. Radial tunnel syndrome is a compression syndrome of the radial nerve, where it passes the outside part of the elbow on its way to the hand through a 5cm long tunnel. The tunnel travels between the surface of a bone on one side and muscles on the other.
The radial nerve subdivides at the elbow into a deep branch and a superficial branch. Compression involving the deep branch of the nerve, called the posterior interosseous nerve (PIN), affects the motor portion of the nerve. The superficial branch affects the sensory portion of the nerve.
Whether compression is on the PIN (motor) or the Superficial branch of the radial nerve (sensory) there are some overlapping symptoms:
- Pain in the forearm
- Extensor muscle weakness (sometimes secondary to pain)
However, PIN is also associated with:
- Pain that worsens when rotating the wrist
- Outer elbow tenderness (sometimes confused with Tennis elbow)
- Decreased ability to grip
- Loss of strength in the forearm, wrist, and hand
- Difficulty extending wrist or rotating the palm up and down
- Difficulty straightening the fingers and thumb
- Painful at the radial tunnel when trying to straighten the middle finger against resistance
The superficial branch is associated with:
- Numbness on the back of the hand and forearm (hairy part)
- Numbness and pins and needles on the thumb side of the forearm
- Achy pain in the forearm
- Sensitivity to touch on the thumb and index finger
- Pain, pain, pain
It is thought that the radial nerve becomes irritated and/or compressed secondary to excessive friction between muscles and the hard bony surface of the forearm bone (Radial head).
Those who have an occupation that requires repetitive tasks may be at an increased risk of developing Radial Tunnel Syndrome. Those who work in construction or manufacturing may be more likely to develop this condition due to the repetitive movements that are required in this type of work, such as:
- Exertions of greater than 1 kg of force more than 10 times per hour
- Static pinching or squeezing of objects or tools
- Working with the elbow extended
- Maintained positioning of the forearm with palm side up or down
While this condition is usually caused by repetitive, forceful motion such as pushing or pulling, or twisting with the hand, in some cases direct injury to the outside of the elbow can also cause Radial Tunnel Syndrome.
It may also be caused by
fractures to the elbow, elbow dislocations, tight muscles, arthritis,
bursitis or elbow tumour. It is important to consider nerve root impingement in the neck as well.
There are several treatment options:
- Rest
- Exercise
- Injection of steroids
- Ice
- Anti-inflammatory medications
- Acupuncture
If these don't work after 6-8 weeks, surgery may be considered
The goal of surgery is nerve decompression by division of fascial bands in the tunnel. During surgery, tissue that is compressed against the radial nerve will be cut and the pressure reduced.
At hand kinetics you can expect to have an assessment of your arm to help guide the diagnosis. Often people have had unsuccessful treatment for tennis elbow before radial tunnel syndrome is considered.
Treatment will therefore aim to reduce symptoms and pain and find which movements cause them. This is individual to the person as symptoms can vary.
Treatment may include:
- Splinting to reduce tension in the nerve while it is healing
- Acupuncture to release muscle tension bands
- Nerve gliding exercises: Which have been advocated to disperse intraneural oedema, increase blood flow, optimise axonal transport, and lengthen nerve adhesion's.
- Stretching exercises: tightness can develop in the muscles secondary to poor posture and may even impinge upon the nerve at the elbow. Therefore, stretching these muscles can reduce impingement on the nerve.
- Prevention: As with most injuries, prevention is the best medicine. It’s important to take frequent breaks when twisting the forearm, extending the wrist or gripping to prevent an overuse injury from occurring.
It is also recommended that if you have an occupation or hobby, such as weight lifting, which exacerbates symptoms, it is important to have a routine examination by a hand therapist to ensure that you aren’t putting too much strain on your muscles and nerves.
Hand Kinetics Telephone: 0044 28 417 72301
www.handkinetics.com
contactus@handkinetics.com