EDN1 and complex regional pain syndrome: The identified biomarkers highlight several pathophysiological processes associated with CRPS, including inflammation (involving interleukins and TNF-α), vascular dysregulation (characterized by imbalances in ET-1 (Endothelin-1) and Nox (nitric oxide derivatives), along with hypoxia-induced elevated lactate), and small fiber neuropathy with hypersensitivity.