Sensorimotor integration in Complex Regional Pain Syndrome: A transcranial magnetic stimulation studyTurton, Ailie J.a,*; McCabe, Candida S.b; Harris, Nigelb; Filipovic, Sasa R.aPAIN: February 2007 - Volume 127 - Issue 3 - p 270–275 doi: 10.1016/j.pain.2006.08.021 Articles Buy Abstract Author InformationAuthors Article MetricsMetrics There is evidence that patients with Complex Regional Pain Syndrome (CRPS) have altered central sensorimotor processing. Sensory input can influence motor output either through indirect pathways or through direct connections from the sensory to motor cortex. The purpose of this study was to investigate sensorimotor interaction via direct connections in patients with CRPS and to compare the results with normal subjects’. Direct short-latency sensory-motor interaction was evaluated in eight patients with CRPS1 affecting a hand. Modulation of EMG responses to transcranial magnetic stimulation (TMS) induced by concomitant median nerve stimulation was measured, the so-called, short-latency afferent inhibition (SAI). Results were compared with eight normal subjects who were age and sex matched with the patients. As expected, all the normal subjects’ EMG responses to TMS with median nerve stimulation were smaller than responses to TMS alone. In seven of the eight CRPS patients EMG responses to TMS were suppressed when paired with median nerve stimulation. Only one CRPS patient's results showed no suppression of EMG responses. These results suggest that the disease mechanisms of CRPS1 do not typically affect the direct neural circuit between sensory and motor cortex and that normal sensorimotor interaction is occurring via this route. aBurden Neurological Institute, Frenchay Hospital, Bristol BS16 1JB, UK bThe Royal National Hospital for Rheumatic Diseases (RNHRD), The School for Health, University of Bath, Bath BA1 1RL, UK *Corresponding author. Tel.: +44 117 9546847; fax: +44 117 9288588. E-mail: Ailie.Turton@bristol.ac.uk Submitted March 22, 2006; revised July 27, 2006; accepted August 21, 2006. © 2007 Lippincott Williams & Wilkins, Inc.