Algodystrophy, M. Sudeck or reflex sympathetic dystrophy (RSD) are terms used in the literature, but now the commonly used term is complex regional pain syndrome (CRPS). CRPS can lead to prolonged pain and permanent disability of the affected limb. Still, the complex pathogenesis of CRPS is incompletely understood. Studies suggest a localised inflammatory response, sympathetic dysregulation, pathologic changes of the nervous system and autonomic dysfunction leading to pain and swelling of the extremity and also to severe bone loss in this limb region. There are many described treatment and prophylaxis modalities, but there is only little high-quality evidence supporting their efficacy (Abd-Elsayed et al. Ann Med 56(1):2334398, 2024; Fassio et al. Rheumatology (Oxford) 61(9):3534–3546, 2022; Varenna et al. Rheumatology (Oxford) 52(3):534–542, 2013; Zhu et al. Pharmaceuticals (Basel) 17(6):811, 2024). CRPS can occur following a major or minor trauma (fracture, joint sprain, ligament tear) or following surgery in a region of the arm or leg. Overall, CRPS is a very rare condition with a prevalence of 6–25 per 100.000 person-years. Mainly, the distal parts of the upper and lower extremities (hand and foot region) are affected. The incidence among women is 2–3 times higher than in men. A fracture of the distal radius (DRF) is the most common diagnosis leading to CRPS I of the hand and wrist region. The prognosis of CRPS is dependent on the stage and severity of the symptoms and is best treated as early as possible. The use of the Budapest CRPS diagnostic criteria should improve the detection rate of CRPS using a validated scoring system (Harden et al. Pain 150(2):268–274, 2010). Three different CRPS types are now described: CRPS I following a trauma, CRPS II following a nerve injury and CRPS-NOS, a type not fulfilling typical criteria (“not otherwise specified”).