Facilitated neurogenic inflammation in unaffected limbs of patients with complex regional pain syndrome.

Pain, edema, increased skin temperature, reddening and trophic changes characterize complex regional pain syndrome (CRPS). Recently, we have been able to show facilitated neurogenic inflammation on the affected limb. In the current study unaffected limbs were examined after resolution of the CRPS symptoms to assess possible generalized changes predisposing to CRPS.

Substance-P-induced protein extravasation is bilaterally increased in complex regional pain syndrome.

Pain, mechanical hyperalgesia, edema, increased skin temperature, and skin reddening are characteristic symptoms of acute complex regional pain syndrome (CRPS). We have recently demonstrated facilitated neurogenic inflammation on the affected limb. To further elucidate the underlying mechanisms, exogenous substance P (SP) in ascending concentrations (10(-9), 10(-8), 10(-7), 10(-6) M) was intradermally applied to the affected and the unaffected limbs, respectively, in two groups of 11 CRPS patients each using the microdialysis technique.