Systemic (Rheumatic)
Complex Regional Pain Syndrome (CRPS)
복합부위통증증후군
Post-traumatic syndrome of severe limb pain with autonomic, motor, and trophic changes
- How common
- 3–7% after limb trauma
- Typical age
- Ages 40–60, female 3:1
What is it?
Post-injury peripheral and central sensitization, neurogenic inflammation, and sympathetic dysfunction cause pain and trophic changes.
Commonly affected: Usually one limb, distal predominance
How it develops
- Trauma/Nerve InjuryFracture, surgery, sprain triggers (Type I no defined nerve, Type II defined)
- Neurogenic InflammationSubstance P/CGRP release → vasodilation, edema
- Central Sensitization + SympatheticDorsal horn amplification + sympathetic-pain coupling
- Trophic/Motor ChangesSkin atrophy, contractures, osteopenia (Sudeck atrophy)
Symptoms
- Burning pain/allodyniaPain disproportionate to injury; even light touch painful
- Autonomic changesSkin color, temperature, sweating asymmetry
- Motor dysfunctionWeakness, tremor, joint contracture
- EdemaDistal edema (acute phase)
- Trophic changesSkin/nail atrophy, hair changes (chronic)
How it is examined
- Budapest criteria3 of 4 symptom categories + 2 of 4 sign categories (sensory/vasomotor/sudomotor-edema/motor-trophic)
- Allodynia/hyperalgesiaSevere pain with brush/cotton touch
- Temperature asymmetry >1°CBilateral comparison with infrared thermometer
- Positive 3-phase bone scanPeriarticular uptake in affected limb (especially chronic)
Imaging
Bone scan shows periarticular uptake in affected limb; X-ray shows patchy osteopenia.
- Patchy osteopenia (Sudeck atrophy)
- Periarticular osteoporosis
- Soft tissue edema
- Bone scan periarticular uptake
MRI shows soft tissue and marrow edema; diagnosis remains clinical (Budapest criteria).
- Soft tissue edema
- Subcutaneous enhancement
- Bone marrow edema (early)
- Muscle atrophy (chronic)
Non-surgical care
- Early PT/OTGraded ROM, mirror therapy, graded motor imagery — cornerstone
- Neuropathic pain agentsGabapentin, pregabalin, amitriptyline, duloxetine
- Bisphosphonates/calcitoninBone loss and pain relief (especially acute phase)
- Sympathetic blockadeStellate ganglion or lumbar sympathetic block
Conservative options are generally tried first. Medications listed here can have side effects — discuss them with your prescriber.
When surgery is considered
Conservative failure, refractory pain
Procedures that may be discussed
- Spinal cord stimulation (SCS)
- DRG stimulation
- Ketamine infusion
- Peripheral nerve stimulation
Outlook
Early diagnosis/treatment yields good outcomes; >1 year increases chronicity risk.