A prolapsed disc or injury to the nerve exit foramen in the neck can give very severe neck and arm pain known as cervical radiculopathy. The sixth cervical nerve is affected in 25% of cases and the seventh in 60% of cases. Of all arm pains of neck origin, about a quarter are due to an acute disc prolapse. With age disc bulges, ligament and joint enlargement and bony osteophytes encroach on the space the nerve has to travel through and this is a more common cause of cervical radiculopathy in older persons. Neck pain from cervical disc prolapse is routinely assessed and treated by physiotherapists.

Risk factors for this type of neck pain and arm pain include smoking, lifting heavy weights regularly (e.g. 12kg, 25 pounds) and driving or operating vibrating equipment. Overall cervical radiculopathy is uncommon and much more so than lumbar disc syndromes such as sciatica. The discs between the vertebrae from C2 to C7 transmit loads down through the spine and dissipate some of the forces applied to it. At the side of the vertebrae are the nerve exits or foramina and the nerve takes up to a third of the exit space normally. Degenerative changes in any of the structures which surround and form the walls of the exit can compromise the exit channel itself and compress the nerve.

The vertebrae from the second to the seventh neck vertebra have discs between them which smooth out shocks applied to the spine and transmit the necessary loads. The bony, disc and joint structures make up the nerve exit channels on the side of the spine and the nerve roots take up to 33% of the available space. If the surrounding structures suffer from degenerative or arthritic changes they can narrow the exit foramen and cause nerve compression.

To ensure the problem is radiculopathy the physio will take a history including the area and type of pain, muscle weakness or numbness, factors making the pain worse or better, how the injury happened, any current treatment and any lower limb or bowel or bladder problems. Commonly the pain has not come on quickly but insidiously and over time, initially presenting with a dull achy pain to a very severe burning pain in the neck and over the shoulder. This can worsen to the upper arm, then the forearm and the hand as the root irritation increases. Rarely there may be no real pain but loss of muscle power and sensibility.

People with root pain look tired due to poor sleep, don't find anything funny and guard their arm in a protective posture against the abdomen or hold it out to the side with their hand on the back of their neck or the other side of the head. This may reduce the forces through the inflamed nerve root and so reduce pain.

On physiotherapy examination patients look tired as they have not slept and they lose their sense of humour. They may hold their arm in a relieving posture cradled across the body or with the elbow out to the side and the hand behind the neck or over the head towards the opposite ear. This may reduce the tension through the irritated or compressed nerve root, reducing the pain.

Initial management is to reduce the inflammation and pain and physiotherapists use cold therapy, anti-inflammatories, manual traction, mechanical traction and instruction to avoid activities or postures which are worsening. The physio reduces the forces applied to the nerve root area with a collar for day or night use to support the neck and limit the available neck movements and with careful manual tractioning to relax muscle spasm and allow the pain to settle.

Reducing the pain and inflammation is the first goal of treatment and the physiotherapist can employ analgesics such as NSAIDs, cryotherapy, mechanical or manual traction and avoidance of aggravating activities and postures. Limiting the forces transmitted through the nerve root is an overall goal of management, using a collar to reduce neck movement, a cervical pillow or collar at night and manual traction from the physio to distract the joints. After the acute phase has settled physiotherapy concentrates on regaining neck movement and muscle power, starting with isometric exercises and moving on to isotonic and exercises for multiple muscle groups. Long term adherence to a regime of aerobic exercise, muscle strengthening and stretching may be useful.