3h - COMPLEX REGIONAL PAIN SYNDROME

Question 1

Definition & overview

Answer 1

• CRPS = chronic neuropathic pain condition characterized by regional pain, sensory disturbances, autonomic
  dysfunction & motor abnormalities, typically following trauma or surgery.
• Divided into:
  o CRPS-I: without confirmed nerve injury.
  o CRPS-II: with confirmed nerve damage (formerly causalgia

Question 2

Key clinical features

Answer 2

Table

Pain disproportionate to initial injury & often spreads beyond original site

Question 3

Pathophysiology: multi-system dysfunction

Answer 3

Table

Question 4

Diagnosis

Answer 4

DIAGNOSIS
- Based on Budapest criteria, requiring symptoms in 3 of 4 categories & signs in 2 of 4 on clinical examination
- Rule out other conditions (infections, neuropathies, arthritis)
- Imaging (bone scan, MRI) & autonomic testing may assist but are not diagnostic

Question 5

Disease progression

Answer 5

Often occurs in stages:
1) Acute: redness, swelling, burning pain.
2) Dystrophic: muscle wasting, increased stiffness, skin changes.
3) Atrophic: persistent pain, contractures, irreversible changes

Question 6

Treatment strategies:
- non-pharmaco
- pharmaco
- invasive procedures

Answer 6

Non-Pharmacological
- Physical therapy: cornerstone to prevent disuse and restore mobility.
- Mirror therapy: helps correct cortical reorganization.
- Graded motor imagery: improves motor control and pain perception.
- Psychological support: CBT, biofeedback, relaxation.

Pharmacological
- NSAIDs, corticosteroids: for inflammation in early phase.
- Antidepressants/Anticonvulsants: e.g., amitriptyline, gabapentin for neuropathic pain.
- Bisphosphonates: reduce bone turnover and pain.
- Calcitonin: shown to reduce acute CRPS pain in some cases.
- Ketamine infusions: NMDA antagonist, used in resistant cases.

Invasive Procedures
- Sympathetic nerve blocks: temporary relief in sympathetically maintained pain.
- Spinal cord stimulation: effective in some chronic cases.
- Intrathecal drug delivery systems: last-resort option