The sympathetic skin response in reflex sympathetic dystrophy.

The sympathetic skin response (SSR) was examined in 12 consecutive patients with reflex sympathetic dystrophy (RSD). It was normal in the involved limbs of five patients, of lower amplitude than on the contralateral side in three and absent only on the involved side in four. The response abnormality was more prominent in patients examined during the first year following the injury. These abnormalities could reflect either the peripheral injury underlying RSD or secondary central nervous system disturbances.