Understanding CRPS
Complex regional pain syndrome (CRPS) is a chronic pain condition that usually develops after an injury, surgery, or even a minor trauma, causing pain that is far more severe and long-lasting than expected. It most often affects one arm or leg and involves changes in skin color, temperature, and swelling in addition to pain. Early diagnosis and treatment, especially active physical therapy alongside pain management, significantly improve outcomes.
Causes
CRPS typically develops after an inciting event, though the exact mechanism varies:
An injury like a fracture, sprain, or surgery, often relatively minor compared to the severity of pain that follows.
Abnormal nervous system signaling, including dysfunction of the sympathetic ("fight or flight") nervous system.
An exaggerated inflammatory response to the initial injury.
Central sensitization, where the nervous system becomes increasingly sensitive to pain signals over time.
CRPS is classified as Type 1 (no confirmed nerve injury) or Type 2 (associated with a confirmed nerve injury); both are treated similarly.
Symptoms
CRPS symptoms typically affect one limb and include:
Severe pain, often described as burning or throbbing, that is disproportionate to the original injury.
Changes in skin color (red, blue, or blotchy) and temperature (warmer or cooler than the other limb).
Swelling in the affected limb.
Changes in sweating, skin texture, or hair and nail growth.
Allodynia (pain from things that shouldn't hurt, like light touch) and heightened sensitivity to pain.
Stiffness and reduced range of motion.
In more advanced cases, muscle weakness or tremor.
Seek prompt medical care if: The limb suddenly becomes cold, pale, or blue, or you develop an open wound or signs of infection.
Imaging Studies to Consider
CRPS is primarily diagnosed clinically, using established diagnostic criteria, with imaging used to support the diagnosis and rule out other causes:
Triple-phase bone scan can show a characteristic pattern of increased uptake in the affected limb, particularly useful earlier in the disease.
X-ray may show patchy bone thinning (demineralization) in later stages.
MRI helps rule out other causes and assess soft tissue changes.
Thermography is occasionally used to document temperature differences between limbs.
Physical Therapy, Home Exercise & Other Conservative Techniques
Early, active physical and occupational therapy is one of the most important and well-studied treatments for CRPS; delaying movement tends to make the condition worse:
Physical Therapy
Graded motor imagery is a structured program that retrains how the brain processes signals from the limb.
Mirror therapy: using a mirror to visually "trick" the brain during movement of the unaffected limb.
Progressive, graded loading and desensitization of the affected limb.
Home Exercise Program
Graded exposure exercises, gradually increasing use of the affected limb.
Contrast baths (alternating warm and cool water) for desensitization.
Gentle active range-of-motion exercises, avoiding prolonged immobilization.
Other Studied Techniques
Desensitization techniques using different textures and temperatures.
TENS (transcutaneous electrical nerve stimulation) as an adjunct to therapy.
Interventional Treatment Options
Interventional treatments, combined with active physical and occupational therapy, are central to CRPS management:
Sympathetic nerve block: A stellate ganglion block (for the arm) or lumbar sympathetic block (for the leg) is a key diagnostic and therapeutic procedure that can significantly reduce pain and improve blood flow.
Continuous peripheral nerve block: Can provide extended pain relief to facilitate participation in intensive physical therapy, which is critical for recovery.
IV ketamine infusion: Considered for refractory cases that haven't responded to other treatments.
Referral to intensive, CRPS-focused physical and occupational therapy: An essential, active component of treatment: desensitization and graded movement help retrain the nervous system.
Acupuncture: A technique that may be considered as part of a broader, multidisciplinary CRPS treatment plan.
Neuromodulation: Spinal Cord & Peripheral Nerve Stimulation
Neuromodulation is one of the most well-established, guideline-recommended treatments for CRPS, with strong supporting evidence:
Spinal cord stimulation (SCS): A guideline-recommended, FDA-approved treatment specifically for CRPS, particularly effective for the lower extremity; a trial period confirms benefit before permanent placement.
Dorsal root ganglion (DRG) stimulation: Particularly effective for CRPS affecting a focal area like the foot, given its precise targeting.
Peripheral nerve stimulation (PNS): An option when CRPS involves a specific, identifiable peripheral nerve.
How Strong Is the Evidence?
A summary of the evidence supporting key treatments for CRPS:
How to read this: Strong means consistent results from multiple high-quality studies. Moderate means generally favorable results with some limitations. Mixed or early means results so far are inconsistent or still emerging. Limited means few or lower-quality studies; these options can still be considered in select cases following a discussion with your healthcare provider.
Spinal cord stimulation: Strong evidence. FDA-approved.
Sympathetic nerve block: Moderate evidence.
Graded motor imagery or mirror therapy: Moderate evidence.
Acupuncture: Limited evidence.
Evidence reviewed November 2026. These ratings summarize published research and major medical society guidelines available at that time. Research continues to evolve, and we will go over the most current evidence for your situation at your visit.
Pain Psychology Techniques
Pain psychology is a core, essential part of CRPS treatment, not because the pain "isn't real," but because CRPS directly involves how the nervous system processes pain and body awareness:
Graded motor imagery and mirror therapy: specific, evidence-based techniques that retrain the brain's map of the affected limb.
Cognitive behavioral therapy (CBT) for pain addresses fear-avoidance and the emotional toll of chronic, severe pain.
Desensitization techniques gradually reduce heightened sensitivity to touch.
Acceptance and commitment therapy (ACT).
Biofeedback.
Non-Opioid Medication Options
Non-opioid medications play a central role in CRPS management, as opioids are generally avoided given limited long-term benefit for this condition:
Nerve pain (neuropathic) medications
Gabapentin or pregabalin calm overactive nerve signaling.
Duloxetine or other antidepressants help manage chronic nerve-related pain.
Other targeted options
Bisphosphonates: some evidence supports their use for bone-related pain in CRPS.
A short oral steroid taper may be used in the early, more inflammatory phase.
Vitamin C: some evidence supports its use to help prevent CRPS after a fracture or surgery.
Topical and anti-inflammatory options
Compounded topical creams or lidocaine for localized relief.
NSAIDs for associated inflammation.
Related Procedures
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Talk With Us About Your Options
Call 650-507-4113 or send us a message to schedule a consultation at our Daly City, Los Altos, or Stockton office. We will review what may be causing your pain and walk through the risks, benefits, and alternatives of each option with you.
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This information is provided for general patient education and does not replace individualized medical advice. Please discuss your specific symptoms, diagnosis, and treatment options with your pain management physician.
