Abstract
Osteoarthropathy is often seen in patients with complex regional pain syndrome (CRPS). The bone pathology is usually accompanied by inflammatory tissue changes that include edema, tenderness, pain, increased temperature and decreased range of motion in the affected joints. The bone pathology seems to share the same underlying mechanisms that occur in Sudeck's bone atrophy and Charcot joints. Recent development of molecular biology in bone metabolism may help understanding the underlying mechanisms of the bony changes. We discussed possible mechanisms to elucidate the bone pathology seen in CRPS. Neuropeptides released from sensory and sympathetic nerves are possible candidates to induce the osteoarthropathy. Cytokines released after tissue injury are other possible candidate to induce the osteoarthropathy. In addition, immobilization itself is also a possible cause to activate osteoclasts and subsequent osteoporosis. Further studies to elucidate the bone pathology associated with CRPS are extremely important for understanding the pathophysiology of CRPS and for its proper treatments.