Complex Regional Pain Syndrome (CRPS)

Budapest Diagnostic Criteria (Current Standard)

Diagnostic Requirements:

1. Continuing pain disproportionate to inciting event
2. Symptoms in ≥3 of 4 categories:
   • Sensory: Allodynia (pain from light touch), hyperalgesia (exaggerated pain)
   • Vasomotor: Temperature asymmetry (greater than 1°C), skin color changes (blotchy, purple, red, pale)
   • Sudomotor/Edema: Swelling, sweating changes (hyperhydrosis or anhydrosis)
   • Motor/Trophic: Decreased ROM, motor dysfunction (weakness, tremor), trophic changes (hair loss, nail changes, skin atrophy)
3. Signs in ≥2 of 4 categories (same as above)
4. No other diagnosis that better explains the symptoms

Clinical Diagnosis:

• Budapest criteria are the current diagnostic standard
• No definitive test confirms CRPS
• Diagnosis is clinical based on criteria
• Early diagnosis improves outcomes

Budapest criteria are the current diagnostic standard for CRPS.

CRPS Type I vs Type II

Type I (formerly RSD):

• No identifiable nerve injury
• Most common (90% of cases)
• After trauma or surgery
• Same treatment approach

Type II (formerly Causalgia):

• Identifiable nerve injury
• Less common (10% of cases)
• After nerve injury
• Same treatment approach

Both types are treated similarly. The distinction is historical but still used. The Budapest criteria apply to both types.

Prevention Strategies

Vitamin C Prophylaxis:

• 500mg daily for 50 days starting peri-operatively
• 50% reduction in CRPS after foot/ankle surgery
• Evidence from multiple RCTs
• Inexpensive and safe
• Use in high-risk cases

Other Prevention:

• Early mobilization (avoid prolonged immobilization)
• Adequate pain control (multimodal analgesia)
• Gentle tissue handling
• Patient education about expectations

Prevention is far superior to treatment.

Treatment of Early CRPS (0-3 months)

Multidisciplinary Approach:

• Physiotherapy: Cornerstone - graded motor imagery, desensitization, mirror therapy
• Medications: Gabapentin/pregabalin first-line, amitriptyline, bisphosphonates
• Sympathetic blocks: Diagnostic and therapeutic
• Psychological support: CBT, pain psychology
• Pain clinic referral: For complex cases

Prognosis: 80-90% improve with early aggressive treatment.

Treatment of Established CRPS (Over 3 months)

Continued Multidisciplinary Approach:

• All treatments from Stage 1
• Spinal cord stimulation: For refractory cases (60-70% success)
• Ketamine infusions: Experimental, limited availability
• Sympathectomy: Last resort, high recurrence

Prognosis: Moderate to poor - 50% have persistent pain and disability.

Surgical Considerations

Prevention:

• Vitamin C 500mg daily for 50 days starting peri-operatively
• Minimize surgical trauma
• Adequate analgesia
• Early mobilization post-operatively

Intra-operative:

• Gentle tissue handling
• Meticulous hemostasis
• Avoid excessive retraction
• Minimize tourniquet time if possible

Post-operative:

• Multimodal analgesia
• Early mobilization
• Monitor for CRPS signs
• Early recognition and treatment if CRPS develops

Prevention through careful surgical technique is key.

Hardware Removal in CRPS

Considerations:

• Hardware removal does NOT reliably improve CRPS
• May worsen symptoms if CRPS is active
• Only remove if hardware is causing problems
• Treat CRPS first, then consider hardware removal if needed

Timing:

• Wait for CRPS to stabilize or improve
• May need to wait months to years
• Individualized decision

Hardware removal is not a treatment for CRPS.

Physiotherapy - Cornerstone of Treatment

Graded Motor Imagery:

• Laterality training (identify left vs right)
• Motor imagery (mental practice)
• Mirror therapy (visual feedback)
• Progressive sequence

Desensitization:

• Progressive tactile stimulation
• Start with soft textures
• Progress to rough textures
• Patient-controlled pace

ROM Exercises:

• Active ROM (patient-controlled)
• Avoid passive aggressive therapy (worsens symptoms)
• Functional restoration
• Weight-bearing as tolerated

Other Techniques:

• Stress loading (weight-bearing activities)
• Normal gait pattern training
• Functional restoration

Physiotherapy is the cornerstone and must be started early.

Medication Management

First-Line (Neuropathic Pain):

• Gabapentin: 300mg nocte, titrate to 300mg TDS (max 900mg daily)
• Pregabalin: 75mg BD, titrate to 150mg BD
• Start low, titrate up
• Monitor for side effects

Second-Line:

• Amitriptyline: 25mg nocte, titrate to 75mg
• Duloxetine: 30-60mg daily
• Bisphosphonates: Alendronate 70mg weekly for 8 weeks (bone pain)

Other:

• NSAIDs: For inflammatory component
• Topical agents: Lidocaine patches, capsaicin cream
• Corticosteroids: Short course in early phase (prednisone taper)
• Avoid opioids: Not effective for neuropathic pain, risk of dependence

Medications are adjuncts to physiotherapy, not primary treatment.

Interventional Procedures

Sympathetic Blocks:

• Lumbar sympathetic block (lower extremity)
• Stellate ganglion block (upper extremity)
• Diagnostic and therapeutic
• Temporary relief (4-12 weeks)
• May facilitate physiotherapy
• Can repeat series of 3 blocks

Spinal Cord Stimulation:

• For refractory cases
• Trial stimulator first
• If greater than 50% pain relief, permanent implant
• Success: 60-70% in selected patients
• Expensive but effective for selected cases

Other:

• IV regional sympathetic blocks
• Ketamine infusions (experimental)
• Sympathectomy (last resort, high recurrence)

Interventional procedures are reserved for refractory cases.

Psychological Support

Essential Component:

• CBT: Cognitive behavioral therapy for pain coping
• Pain psychology: Address anxiety/depression
• Biofeedback: Relaxation techniques
• Acceptance and commitment therapy

Rationale:

• Psychological factors contribute to CRPS
• Anxiety and depression are common comorbidities
• Psychological support improves outcomes
• Essential part of multidisciplinary approach

Psychological support is essential, not optional.