Complex Regional Pain Syndrome I as a Small-Fiber Neuropathy

A review of evidence that supports this often-overlooked pathology as a cause of CRPS I

Complex regional pain syndrome (CRPS) is currently classified as having two forms: CRPS I (formerly called reflex sympathetic dystrophy), with no neuronal damage detected; and CRPS II, with identified nerve damage. In this overview, the authors present experimental and pathological evidence that CRPS I is a posttraumatic neuropathy caused by distal degeneration of small-diameter peripheral axons, which is often overlooked.

The authors review extensive pathological evidence from amputated extremities of patients with severe CRPS I and integrate these findings with the known neurobiology of small fibers, experimental small-fiber lesion studies, and the results of skin biopsy in patients with CRPS I. These studies make clear that patients with …

Reviewing Author

Robert J. Schwartzman, MD