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English: Overview of afferent, efferent and central mechanisms that contribute to complex regional pain syndrome. Different afferent (transit signals to the central nervous system), efferent (transit signals away from the central nervous system) and central mechanisms play a role in CRPS. Afferent mechanisms are inflammation, small fibre neuropathy and vasomotor dysfunction through endothelial dysfunction and adrenergic receptor upregulation; efferent mechanisms are autonomic dysregulation, central sensitisation through NMDA receptor upregulation and GABA-mediated motor disturbances; and central mechanisms are neuroinflammation and cortical reorganisation. Derived from the Handbook of Pain Medicine [207]. CGRP calcitonin gene-related peptide, CRPS complex regional pain syndrome, ET-1 endothelin-1, GABA γ-aminobutyric acid, Ig immunoglobulin, IL interleukin, NO nitric oxide, NMDA N-methyl-d-aspartate, TNF tumour necrosis factor