CRPS Type II Post-Fracture Rehabilitation: Graded Motor Imagery and Desensitisation
In short
Complex Regional Pain Syndrome Type II (causalgia) can develop following fractures with nerve injury. Learn the 3-stage Graded Motor Imagery protocol to recalibrate the brain and restore pain-free limb function.
In this guide (6 sections)
Complex Regional Pain Syndrome (CRPS) is a severe, chronic pain condition that can arise following limb fractures, crush injuries, or orthopaedic surgery. While CRPS Type I occurs without a verifiable major nerve injury, CRPS Type II (historically known as causalgia) develops in the presence of an identifiable peripheral nerve lesion, such as median nerve stretch in distal radius fractures or peroneal nerve injury in fibular fractures. Characterized by continuous burning pain that is profoundly disproportionate to the inciting event, CRPS features allodynia (pain from normally non-painful stimuli like light touch or breezes), hyperalgesia, autonomic dysfunction (mottled skin discoloration, temperature asymmetry, localized sweating abnormalities), brawny oedema, and trophic changes in hair and nails. Physiotherapy must avoid aggressive passive manipulation: which triggers massive sympathetic flares: and instead apply neuro-plastic re-education through the evidence-based Graded Motor Imagery (GMI) protocol.
Domestic and Cultural Indian Realities
Living with CRPS in an Indian home requires deep environmental and emotional understanding. The intense allodynia makes everyday sensations excruciating: the gentle touch of a silk saree, water splashing from a bath mug (lota), or the breeze from a ceiling fan can trigger agony; ceiling fan speeds must be modulated and clothing kept loose, soft, and unrestrictive. Cultural traditions like touching elders feet (charan sparsh) or receiving handshakes in social gatherings create acute anxiety; family members must be educated about sensory allodynia. Washing kitchen cookware, handling hot cooking spices (mustard seeds, turmeric, chili powders), and cooking over open gas stoves generate heat and tactile stress that exacerbate burning sensations; patients should be relieved of kitchen duties during early neural recalibration. Commuting in noisy, jarring autorickshaws amplifies sympathetic nervous system arousal; domestic travel must be peaceful and conducted in climate-controlled cars.
Clinical Biomechanics and Anatomical Healing
The pathophysiology of CRPS involves profound neuro-inflammation, peripheral sensitization, sympathetic-afferent coupling, and central maladaptive neuroplasticity. Within the primary somatosensory cortex (S1), the cortical representation of the affected limb shrinks and blurs (cortical smudging), distorting body perception. Traditional forced physiotherapy activates protective threat circuitry in the amygdala and dorsal horn, worsening hyperalgesia. Graded Motor Imagery (GMI) systematically reactivates premotor and motor cortical networks sequentially without activating pain-producing sensory threat pathways. By progressing through implicit motor imagery, explicit motor imagery, and mirror therapy, GMI restores normal cortical representation and dampens central sensitization.
Validated Special Tests and Differential Diagnosis
Clinical diagnosis utilizes the internationally validated Budapest Criteria, requiring continuous pain disproportionate to inciting trauma alongside symptoms across at least three categories (sensory, vasomotor, sudomotor/oedema, and motor/trophic). Allodynia is demonstrated by lightly brushing a cotton swab across the skin, while hyperalgesia is assessed with gentle pinprick testing. Skin temperature differences between limbs (greater than 1 degree Celsius) are verified using an infrared cutaneous thermometer. Differential diagnosis rules out deep infection, deep vein thrombosis, and persistent fracture non-union.
Stage-by-Stage Functional Recovery Protocol
Step 1 of Graded Motor Imagery (Weeks 0 to 2) involves Implicit Motor Imagery (Left/Right Limb Judgement training using flashcards or mobile apps), recognizing limb laterality without moving the arm or leg. Step 2 (Weeks 2 to 4) advances to Explicit Motor Imagery (Imagined Movements), mentally visualizing smooth, pain-free movements without physical muscle contraction. Step 3 (Weeks 4 to 8) introduces Mirror Therapy, placing a mirror between the limbs so the brain observes the reflected uninjured limb moving effortlessly while the injured limb rests hidden. Step 4 (Weeks 8 to 16) initiates gentle progressive sensory desensitisation and functional weight-bearing (scrubbing and carrying drills).
Mirror Therapy Visual Motor Retraining
Objective: Deliver pain-free visual feedback to the brain to recalibrate the cortical somatosensory map
- 1Sit comfortably at a sturdy table with a clean vertical mirror placed between your arms with the reflecting surface facing your uninjured arm.
- 2Position your injured arm completely behind the mirror so it is hidden from your line of sight.
- 3Look intently into the mirror reflection, watching the image of your moving uninjured hand and wrist.
- 4Perform gentle, slow, pain-free movements with the uninjured hand: opening fingers, making a gentle fist, and rotating the wrist.
- 5Focus your attention on tricking your brain into perceiving that the reflected image is your operated limb moving smoothly without pain.
- 6Keep the hidden injured arm completely relaxed without forcing it to mirror the movement if painful.
| GMI Protocol Stage | Clinical Neurological Target | Specific Patient Activity | Success Criteria to Advance |
|---|---|---|---|
| Step 1: Left/Right Laterality | Premotor cortex activation without motor trigger | Identify left vs right limb images on flashcards/app | Accuracy greater than 80%; speed under 1.6 seconds |
| Step 2: Imagined Movements | Motor planning network recruitment without movement | Mentally visualize adopting pain-free limb postures | Visualize movements without triggering sympathetic pain |
| Step 3: Mirror Visual Therapy | Primary motor and sensory cortex recalibration | Watch reflection of moving healthy limb in mirror | Painless perception of limb movement; decreased allodynia |
| Step 4: Tactile Desensitisation | Dorsal horn sensory gating and cortical unsmudging | Progressive textures (silk, cotton, wool, denim) | Tolerance to light clothing contact and water spray |
Red Flags and Urgent Surgical Indicators
Seek immediate medical evaluation if you develop severe, rapidly expanding swelling accompanied by a pale, cold, pulseless extremity, which signals acute arterial compromise. Progressive severe muscle wasting, joint contractures, or skin breakdown with ulceration requires urgent multidisciplinary pain specialist consultation. Unbearable neuropathic pain resistant to conservative care may warrant consideration of sympathetic nerve blocks or spinal cord stimulation.
Frequently Asked Questions
Why does gentle touch like clothing or a fan breeze cause such intense pain in CRPS?
In CRPS, the central nervous system becomes hyper-sensitized, a state known as allodynia. The pain-processing circuits in the spinal cord and brain undergo physical reorganization so that normal light touch signals (carried by large beta fibers) are misinterpreted by the brain as severe, burning injury signals.
Can I use ice packs or hot fomentation to relieve CRPS burning pain?
Extreme temperatures should be avoided. Ice packs can trigger intense sympathetic vasoconstriction and worsen burning causalgia, while hot fomentation can increase inflammatory swelling. Neutral, lukewarm water or room-temperature sensory stimuli are the safest approaches for nerve calming.
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