Complex regional pain syndrome (CRPS)

What is CRPS?

This is a poorly understood condition associated with severe pain, swelling, and skin changes, particularly after a nerve injury.

Synonym of CRPS

1. Complex regional pain syndrome (CRPS)
2. Sudeck’s atrophy
3. Sympathetic dystrophy
4. Algodystrophy
5. Causalgia

Causes of CRPS

• Trauma
• A different surgical operation like an arthroscopy for knee pain
• A peripheral knee lesion
• Myocardial infarction
• Stroke
• Hemiplegia

Clinical features

1. Burning pain and sometimes cold intolerance in the affected area, usually the hand or foot, sometimes the knee or hip, and sometimes the shoulder.
2. Pain out of proportion (in both intensity and duration) to the precipitating cause
3. In mild cases:

• Slight swelling, with tenderness and stiffness of the nearby joints
• Local redness and warmth, sometimes changing to cyanosis with a blotchy, cold and sweaty skin

4. In severe cases: Trophic changes become apparent: a smooth shiny skin with scanty hair and atrophic, brittle nails
5. In the most advanced stage: severe joint stiffness and fixed deformities

Treatment

Mild cases:

1. A simple regimen of reassurance
2. Anti-inflammatory drugs
3. Physiotherapy

In moderate and advanced cases

1. Analgesics and anti-inflammatory drugs
2. Local injections to painful areas
3. Local counter-irritants.
4. Acupuncture
5. Transcutaneous nerve stimulation
6. Sympathetic block
7. Surgical interruption of pain pathways