TNF-α in CRPS and 'normal' trauma--significant differences between tissue and serum.

Posttraumatic TNF-alpha signaling may be one of the factors responsible for pain and hyperalgesia in complex regional pain syndromes (CRPS). In order to further specify the role of TNF-alpha we investigated tissue (skin) and serum concentrations in three different patient groups: patients with osteoarthritis and planned surgery, with acute traumatic upper limb bone fracture waiting for surgery, and with CRPS I. Thirty patients (10 in each group) were recruited. Mean CRPS duration was 36.1 ± 8.1 weeks (range 8- 90 weeks). Skin punch biopsies were taken at the beginning of the surgery in osteoarthritis and fracture patients and from the affected side in CRPS patients. Blood samples were taken…