Neurology · Pain Syndromes
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Diagnosis of Complex Regional Pain Syndrome (CRPS) is based on the Budapest Criteria, requiring symptoms in at least 3 of 4 categories (sensory, vasomotor, sudomotor/edema, motor/trophic) and signs in at least 2 categories.
Patients typically present with disproportionate, regional pain that is allodynia or hyperalgesia following a minor injury or surgery.
Physical examination reveals autonomic instability characterized by skin color changes, temperature asymmetry, and edema in the affected extremity.
Chronic stages of the disease often manifest as trophic changes including hair growth abnormalities, nail brittleness, and skin atrophy.
Initial management for CRPS involves physical and occupational therapy combined with NSAIDs or neuropathic pain agents like gabapentin or amitriptyline.
Refractory cases may require bisphosphonates for bone resorption or sympathetic nerve blocks to address the underlying sympathetic nervous system overactivity.
Early mobilization and vitamin C supplementation following distal radius fractures are recommended to reduce the incidence of CRPS Type I.
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A 45-year-old woman presents to the clinic with persistent burning pain in her right hand three months after a distal radius fracture. She reports that even the light touch of her clothing causes severe pain. On examination, the right hand is edematous and appears mottled compared to the left. There is temperature asymmetry with the right hand feeling significantly cooler. She also exhibits hypertrichosis and nail dystrophy on the affected digits.
What is the most likely diagnosis?
Complex Regional Pain Syndrome (CRPS)
The patient meets the Budapest Criteria for CRPS, characterized by regional pain disproportionate to the inciting event, accompanied by autonomic (temperature/color), sudomotor (edema), and trophic (hair/nail) changes.
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Etiology / Epidemiology
Occurs post-trauma/surgery in females (3:1). Often follows distal radius fractures or nerve injury.
Clinical Manifestations
Pain out of proportion to injury; allodynia and autonomic dysfunction (color/temp changes).
Diagnosis
Clinical diagnosis via Budapest Criteria. Three-phase bone scan is the most sensitive imaging.
Treatment
NSAIDs for mild cases; bisphosphonates or gabapentin for neuropathic pain. Avoid opioids.
Prognosis
Early intervention is critical to prevent permanent limb atrophy and contractures.
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Epidemiology & Etiology
Most common in post-menopausal women following minor trauma or orthopedic surgery. It is a disorder of the autonomic nervous system triggered by tissue injury. Incidence peaks between ages 40-60.
Pertinent Anatomy
Typically affects the distal extremities (hands or feet). The condition involves the peripheral nerves and the sympathetic nervous system, leading to regional rather than dermatomal distribution.
Pathophysiology
Involves neurogenic inflammation and peripheral sensitization. Sustained sympathetic activation leads to vasomotor instability and sudomotor changes. Central sensitization occurs as the condition progresses, causing pain to spread beyond the original injury site.
Clinical Manifestations
Patients present with allodynia (pain from non-painful stimuli) and hyperalgesia. Look for autonomic signs: skin color changes (mottling), temperature asymmetry, and edema. Red flags include muscle atrophy and fixed joint contractures indicating late-stage disease.
Diagnosis
Diagnosis is strictly clinical using the Budapest Criteria, requiring symptoms in 3 of 4 categories (sensory, vasomotor, sudomotor/edema, motor/trophic). A three-phase bone scan is the most sensitive test, showing increased uptake in the affected limb. MRI may be used to rule out other pathologies.
Treatment
First-line therapy includes NSAIDs for inflammation and gabapentin or pregabalin for neuropathic pain. Bisphosphonates are effective for bone pain. Avoid opioids due to lack of efficacy and high risk of dependence. Physical therapy is mandatory to prevent permanent contractures.
Prognosis
Prognosis is best with early mobilization and multidisciplinary care. Without treatment, patients risk permanent disability and chronic regional pain. Long-term monitoring for osteoporosis and psychological distress is required.
Differential Diagnosis
Cellulitis: presence of fever and systemic leukocytosis
DVT: positive Homan sign and venous duplex ultrasound findings
Peripheral Neuropathy: typically bilateral and stocking-glove distribution
Thoracic Outlet Syndrome: pain localized to the brachial plexus distribution
Factitious Disorder: lack of objective autonomic findings