What is the appropriate diagnosis and treatment plan for Complex Regional Pain Syndrome?

Complex Regional Pain Syndrome: Diagnosis and Treatment

Diagnosis

Complex Regional Pain Syndrome (CRPS) is diagnosed clinically using the Budapest Criteria, requiring continuous pain disproportionate to the inciting event, with sensory, vasomotor, sudomotor/edema, and motor/trophic abnormalities present. 1, 2

Clinical Presentation to Identify

• Pain characteristics: Excruciating, burning pain that gradually increases in intensity, spreads within the affected limb, and worsens with touch or stimulation 1, 3
• Sensory abnormalities: Allodynia (pain from non-painful stimuli) and hyperalgesia (exaggerated pain response) are hallmark features 1, 2
• Autonomic dysfunction: Temperature dysregulation, skin color changes (red, blue, or mottled), and abnormal sweating patterns in the affected limb 1, 3
• Motor impairment: Functional limb weakness and decreased active range of motion disproportionate to the injury 1
• Trophic changes: Hair loss, tissue changes, and skin discoloration in chronic cases 1

Diagnostic Imaging

Three-phase bone scintigraphy is the most useful imaging modality for CRPS, with 78% sensitivity and 88% specificity. 4, 1

• MRI has higher specificity (91%) but lower sensitivity (35%), making it unsuitable as a screening test 1
• Imaging is not required for diagnosis but can help rule out alternative diagnoses 4

CRPS Classification

• Type I (formerly reflex sympathetic dystrophy): No identifiable nerve injury 1, 3
• Type II (formerly causalgia): Confirmed nerve injury documented through clinical examination or diagnostic testing 1, 3

Treatment Algorithm

Immediate First-Line Treatment (All Patients)

Physical and occupational therapy with gentle mobilization and progressive exercises is the cornerstone of CRPS treatment and must be initiated immediately—all other interventions serve solely to facilitate participation in rehabilitation. 1, 5

Critical pitfall: Delaying physical therapy while waiting for pain to resolve worsens outcomes through disuse and pain upregulation 1, 5

Physical Therapy Components

• Gentle stretching and mobilization focusing on increasing external rotation and abduction 5
• Active range of motion exercises that gradually increase while restoring alignment 5
• Sensorimotor integration training to normalize movement patterns and prevent limited range of motion 5

Pharmacologic Management to Enable Rehabilitation

NSAIDs (ibuprofen) or acetaminophen are first-line analgesics if no contraindications exist. 5

• Early oral corticosteroids (30-50 mg daily for 3-5 days, then taper over 1-2 weeks) may reduce swelling and inflammation in acute CRPS 5, 2
• Tricyclic antidepressants (amitriptyline, nortriptyline) for neuropathic features 5
• Gabapentin or pregabalin for neuropathic pain component 5, 2
• Topical lidocaine for localized neuropathic pain 5

Important: All neuropathic pain medications must be trialed at appropriate doses for at least 2 weeks before changing to another option 4

Interventional Procedures for Moderate to Severe Cases

Sympathetic nerve blocks (stellate ganglion for upper extremity, lumbar sympathetic for lower extremity) may be used when sympathetically maintained pain prevents physical therapy participation, but only if each successive block demonstrates consistent improvement with increasing duration of relief. 1, 5

Critical pitfalls to avoid:

• Continuing sympathetic blocks indefinitely without documented progressive improvement and increasing duration of relief 1
• Using peripheral somatic nerve blocks for long-term treatment 1, 5
• Using sympathetic blocks for non-CRPS neuropathic pain 1, 5

Advanced Neuromodulation for Refractory Cases

Spinal cord stimulation is recommended for persistent CRPS that has failed multimodal conservative treatment, with a mandatory trial period required before permanent device implantation. 5, 6

• Trial must demonstrate adequate pain relief and functional improvement before permanent implantation 5
• Strong consensus supports spinal cord stimulation for refractory CRPS 5

Psychological Interventions

Cognitive behavioral therapy, biofeedback, and relaxation training reduce anxiety and avoidance behaviors that perpetuate disability. 5, 6

• These interventions should be integrated early, not reserved for treatment failures 5

Documentation Requirements for Ongoing Treatment

Documenting objective functional outcomes is essential—not just pain scores—including measurable improvements in activities of daily living, cognitive function, autonomic stability, and temperature dysregulation. 5

• For sympathetic blocks: Record duration of relief with each successive block to demonstrate the required pattern of "increasing duration" 5
• Failing to document objective functional outcomes beyond pain scores cannot justify continued interventional treatment 1

Monitoring and Follow-Up

Evaluate CRPS patients at least twice annually by a specialist due to high recurrence risk. 1, 5

• Ongoing reassessment of functional status, not just pain scores, is essential 5
• Non-recovering patients should be re-evaluated for neurosurgically treatable causal lesions (nerve entrapment, impingement, infections, or tumors) and treatable potentiating conditions including polyneuropathy and circulatory insufficiency 3

Prognosis

Most patients, particularly the young, recover gradually with appropriate treatment 3, 7. Children with CRPS benefit from multifaceted physical therapy leading to a high percentage becoming symptom-free 7. Early diagnosis and aggressive management are critical because long-term outcomes improve when treatment is initiated soon after symptom onset 2, 6.