Osteoprotegerin: a new biomarker for impaired bone metabolism in complex regional pain syndrome?

Abstract Osteoprotegerin (OPG) is important for bone remodeling and may contribute to complex regional pain syndrome (CRPS) pathophysiology. We aimed to assess the value of OPG as a biomarker for CRPS and a possible correlation with radiotracer uptake in 3-phase bone scintigraphy (TPBS). OPG levels were analyzed in 23 CRPS patients (17 women; mean age 50 ± 9.0 years; disease duration: 12 weeks [IQR 8–24]), 10 controls (6 women; mean age 58 ± 9.6 years) and 21 patients after uncomplicated fractures (12 women; mean age: 43 ± 15 years; time after fracture: 15 weeks [IQR: 6–22]). The CRPS and control patients also underwent TPBS. OPG in CRPS patients was significantly increased by comparison wi…