Upper Limb Dermatomes

The upper limb dermatomes describe areas of skin that receive their main sensory supply from individual cervical and upper thoracic spinal nerve roots. Although there is considerable overlap between neighbouring dermatomes, recognising the general pattern of symptoms can help a pain specialist determine whether pain or altered sensation may be originating from a cervical spinal nerve root.

Patients with cervical nerve-root irritation may experience pain beginning in the neck and travelling into the shoulder, arm, forearm or hand. Depending on the affected nerve root, symptoms may be felt in different areas—for example, around the shoulder and upper arm, along the thumb side of the arm and hand, or towards the little-finger side of the hand. Symptoms may include shooting or electric-shock-like pain, burning, pins and needles, numbness or increased sensitivity to touch. Weakness or changes in reflexes can also occur when the motor component of a spinal nerve is affected.

A dermatomal pattern can be particularly useful when assessing cervical radiculopathy, but it is not diagnostic on its own. Symptoms may overlap between nerve roots, and conditions involving the shoulder, peripheral nerves, muscles or joints can produce similar symptoms. A detailed clinical assessment is therefore important, with imaging or nerve conduction/EMG studies considered when clinically appropriate.

Treatment depends on the underlying cause and severity of the symptoms. Many patients initially benefit from conservative treatment, including activity modification, physiotherapy, exercise-based rehabilitation and appropriate medication. Where nerve-root inflammation or compression is contributing significantly to pain, image-guided procedures may sometimes form part of a comprehensive treatment plan. Depending on the clinical circumstances, these may include a Dorsal Root Ganglion Block, Dorsal Root Ganglion Pulsed Radiofrequency or Epidural Steroid Injection. These procedures have different purposes and are selected according to the suspected pain generator, clinical findings and individual patient factors. Epidural steroid injections, for example, may provide short-term relief for some patients with radicular pain associated with disc herniation.