The motor and sensory systems are complex. In order to initiate movement, nerve cells on the surface of the brain need to fire. These messages are modulated by other nerves deep in the brain and travel down fibres in the spine where they join spinal nerves that supply muscles in our limbs. Similarly when sensory nerve endings are stimulated in the skin, messages travel to the spinal cord and then the brain where the information is integrated.

Weakness or altered sensation may be caused by a simple trapped nerve such as a carpal tunnel syndrome, a spinal disc irritating a nerve root such as sciatica or by other more serious brain or spinal problems.

Assessment of a patient with weakness or sensory symptoms therefore requires a detailed clinical examination. The assessment is supported by investigations. If the problem is thought to be in the brain or spinal cord I arrange a detailed MRI scan. If the problem is thought to be in the peripheral nerves I arrange nerve conduction tests. In some patients we do not identify a structural cause and we explore whether there may be other psychological factors that may be contributing.