Introduction: Complex regional pain syndrome (CRPS) is a relatively rare disorder, but one that is extremely serious for the affected patient. It usually occurs in the area distal to a primary limb injury. The clinical symptoms and the pain are out of all proportion to the inciting event and in approximately 10 % of CRPS patients, there is no triggering event at all. CRPS leads to long-term disability and high treatment and follow-up costs In about half of those affected. Clinical symptoms: Two forms exist. In CRPS type 1, no nerve lesions are present, whereas in CRPS type 2, injury has occurred to a nerve or the main branch of a nerve. However, in terms of their clinical course, there is no difference between the two forms. Approximately 90 % of all cases involve CRPS type 1, formerly known as "Sudeck's atrophy". The cardinal symptom is pain. In addition, trophic disturbances, such as swelling, local skin discolouration or asymmetric skin temperatures, can also occur. Impaired mobility and function of the affected limb also occur frequently and are very difficult to treat. Diagnosis: Initially, it can be difficult to distinguish between CRPS and a normal post-traumatic course. Subsequently, the severe symptoms are out of all proportion to the in-citing event. The diagnosis of CRPS is based mainly on the clinical symptoms. The Budapest criteria help to confirm the diagnosis. Therapy: Early and interdisciplinary rehabilitation is of crucial importance in CRPS treatment. Occupational therapy and physiotherapy are supplemented by good analgesic management and psychological support, if required. Analgesia should be based on the WHO pain ladder. Methadone is of proven efficacy in cases of severe hyperalgesia and gabapentin or pregabalin are used to treat refractory pain. Bisphosphonates have shown a good analgesic effect, particularly in patients with confirmed bone lesions. Chronic oedema and inflammation may require short-term steroid administration. A further clinical goal is the avoidance of sequelae, such as osteoporosis. Patients with suspected CRPS should be referred to a multidisciplinary treatment team, preferably one with considerable experience in treating this clinical presentation. One physician should coordinate the patient's treatment. The earlier the treatment is started, the better the prognosis.
