Multiple sclerosis-related central pain disorders.

Central neuropathic pain is common in multiple sclerosis (MS), and its prevalence increases with physical disability. Sufficient evidence links dysesthetic pain, trigeminal neuralgia, Lhermitte's sign, and painful tonics spasms to plaque formation in the spinal cord and brain, whereas the association with headache and back pain remains unclear. Management varies according to the pain in question.