# Complex regional pain syndrome | Symptoms, Causes, Tests and Treatment | OSANG > CRPS was previously called reflex sympathetic dystrophy (RSD) or Kausalgia. It is characterized by relatively severe pain that persists after trauma and is accompanied b… - Official page: https://osns.co.kr/en/encyclopedia/complex-regional-pain-syndrome - Organization: OSANG Neurosurgery ## Page content Pain Medicine ## Complex regional pain syndrome Complex Regional Pain Syndrome · G90.50 Complex regional pain syndrome (CRPS) is a chronic pain condition that occurs after trauma or nerve damage and is accompanied by persistent pain that is severe and disproportionate to the pain stimulus, autonomic dysfunction (skin temperature and color changes, sweating abnormalities), motor dysfunction, and nutritional changes (edema, skin, hair, and nail abnormalities). ## At a glance CRPS was previously called reflex sympathetic dystrophy (RSD) or Kausalgia. It is characterized by relatively severe pain that persists after trauma and is accompanied by autonomic dysfunction and motor impairment in the affected limb. The incidence is reported to be approximately 5 to 26 per 100,000 population, and is approximately 3 to 4 times more common in women. Early diagnosis and multidisciplinary treatment are critical to prognosis. - 01Definition and Overview - 02Causes and Mechanisms - 03symptoms - 04treatment ## Definition and Overview Complex regional pain syndrome (CRPS) is a chronic pain condition that persists beyond the normally expected healing period following trauma, surgery, or nerve injury. The intensity and duration of pain are unbalanced with the triggering stimulus, and are accompanied by autonomic dysfunction, movement disorders, and nutritional changes. CRPS Type I occurs without obvious nerve damage and was previously called reflex sympathetic dystrophy (RSD). CRPS Type II occurs after direct damage to peripheral nerves and was previously called causalgia. The incidence is approximately 5 to 26 per 100,000 population, and is approximately 3 to 4 times more common in women. It occurs slightly more frequently in the upper extremities (after a wrist fracture) than in the lower extremities. ## Causes and Mechanisms ### neuroinflammation After trauma, the release of neuropeptides such as Substance P and CGRP continues from peripheral sensory nerves, causing vasodilation, edema, and inflammation. This neurogenic inflammation abnormally persists even after the normal tissue healing response. ### central sensitization Continuous input of peripheral pain signals sensitizes pain processing neurons in the dorsal horn of the spinal cord (central sensitization), causing extreme pain even with mild stimulation. Reorganization of the brain's pain processing circuitry and body schema also contributes to the sensory and motor abnormalities of CRPS. ### Sympathetic overactivation Abnormal sympathetic nerve activity in the affected limb is involved in maintaining pain. There are cases where abnormal sensitivity of peripheral sensory nerves to norepinephrine is formed, resulting in sympathetically maintained pain (SMP), in which pain worsens when sympathetic nerves are activated. ## symptoms ### Budapest diagnostic criteria The official diagnostic criteria for CRPS are the Budapest Criteria (2010). Clinician Criteria: Must have symptoms in at least 3 of the following 4 categories and signs in at least 2 of the following 4 categories: 1. Sensory: Symptoms or signs of allodynia, hyperalgesia 2. Vasomotor: Symptoms or signs of skin temperature asymmetry and skin color changes 3. Sweating/Swelling: Symptoms or signs of abnormal sweating and swelling of extremities. 4. Exercise/Nutrition: Symptoms or signs of decreased range of motion, movement disorders (tremors, dystonia, muscle weakness), nutritional changes (hair, nails, skin) Additionally, the symptoms must not be better explained by another diagnosis. ### Stage - Acute stage (weeks to months): Pain, swelling, skin warmth and redness - Dystrophy phase (several months to years): Reduction of edema, skin cooling, skin and hair changes - Atrophic phase (several years): skin atrophy, joint contractures, osteoporosis ## treatment ### Physical therapy and occupational therapy The role of physical therapy in CRPS treatment is key. ‘Desensitization’ training and graded motor imagery (GMI), which gradually activate the affected limb within the pain range, are effective. Studies have shown that progressive motor imagery therapy significantly improved pain intensity and function in patients with CRPS over the long term. ### medication - Nonsteroidal anti-inflammatory drugs (NSAIDs): Control acute pain and inflammation. - Pregabalin, Gabapentin: Control of neuropathic pain. - Antidepressants (amitriptyline, duloxetine): Central sensitization and pain control. - Bisphosphonates: Reduce bone resorption, some studies report improvement in pain - Steroids: short-term use in the acute inflammatory phase. ### Nerve block treatment Sympathetic nerve blocks are used to relieve pain and improve the ability to perform physical therapy in CRPS patients with confirmed SMP. For upper extremity CRPS, stellate ganglion block is performed, and for lower extremity CRPS, lumbar sympathetic nerve block is performed. ### Spinal Cord Stimulation (SCS) There is evidence that spinal cord stimulation is effective in controlling long-term pain in chronic CRPS that does not respond to conservative treatment. ## Frequently asked questions ### Q01Why does CRPS occur? The pathogenesis of CRPS has not been fully elucidated, but it is a combination of neuroinflammation, central sensitization, sympathetic nervous system hyperactivation, and immune response abnormalities that abnormally persist after tissue damage. The severity of the trauma and the risk of developing CRPS are not always proportional, and can occur even after minor sprains. ### Q02What is the difference between CRPS type 1 and 2? CRPS type 1 (formerly known as reflex sympathetic dystrophy, RSD) occurs without obvious nerve damage. CRPS type 2 (formerly Kausalzia) occurs after obvious damage to the peripheral nerves. Clinical symptoms and treatment approaches are similar in both types. ### Q03What does CRPS pain feel like? It is characterized by constant burning and stabbing pain. It is accompanied by allodynia, which causes severe pain even when a stimulus as mild as rubbing against clothes, and hyperalgesia, which causes an excessive response to painful stimuli. The affected limb has a different temperature than other limbs and is accompanied by color changes (redness or cyanosis), edema, and abnormal sweating. ### Q04Why is it important to get CRPS treated early? If you start active rehabilitation and treatment at the beginning of the disease, you can prevent it from becoming chronic. As pain and autonomic abnormalities persist, central sensitization becomes stronger and treatment becomes more difficult. Early physical therapy, pain control, and education are critical to improving prognosis. ### Q05Is stellate ganglion block effective for CRPS? If there is sympathetically maintained pain in upper extremity CRPS, stellate ganglion block may help reduce pain and improve blood circulation. The rehabilitation effect is high when physical therapy is combined after block surgery. There is also CRPS (sympathetically independent pain) that does not respond to sympathetic nerve blockade, so it is also used for diagnostic purposes to confirm response to treatment. ### Q06Can people with CRPS exercise? If the affected limb is not used due to pain, atrophy and pain sensitization worsen. Physical therapy and occupational therapy to gradually use the limbs within the pain range are important. Mirror therapy and graded motor imagery help normalize the body maps of the central nervous system. ## Related articles - fibromyalgia This article provides general medical information and does not replace an individual diagnosis or treatment plan. Please seek a medical assessment if symptoms persist. ## Important notice This Markdown alternative helps search and AI tools understand the public page accurately. It provides general health information and does not replace an individual diagnosis or treatment.