Challenging pain syndromes: Parsonage-Turner syndrome.

Parsonage-Turner syndrome (PTS) is a rare disorder typically characterized by an abrupt onset of upper extremity pain followed by progressive neurologic deficits, including weakness, atrophy, and occasionally sensory abnormalities. The exact cause and pathophysiology of PTS are complex and incompletely understood. Autoimmune, genetic, infectious, and mechanical processes have all been implicated. No specific treatments have been proven to reduce neurologic impairment or improve the prognosis of PTS. Most patients with PTS are treated with a multidisciplinary approach that includes both physical therapy and pharmacologic treatment, often with multiple agents. Further research is needed.