The Clinical journal of pain
-
Nondermatomal somatosensory deficits (NDSDs) not conforming to the distribution of peripheral nerves or dermatomes, and often present after a minor injury or with no known inciting event, have long been associated with "hysteria." This article reviews the modern literature concerning NDSDs associated with chronic pain with regard to their prevalence, phenomenology and clinical presentation, clinical assessment, etiology and pathophysiology, relationship with Conversion Disorder and psychological factors, and their treatment and prognosis. ⋯ NDSDs are important and prevalent clinical phenomena associated with chronic pain. Their prevalence in the general population, primary care settings, and non pain patients is unknown. Research needs to be carried out to elucidate these important phenomena.