Complex regional pain syndrome (CRPS) can occur at any age, but usually affects men and women in their early- to mid-forties, with women more likely to be impacted. CRPS is chronic arm or leg pain that develops after an injury, stroke, surgery, or heart attack. The pain is localised and often disproportionate to the initial trauma.
Causes of Complex Regional Pain Syndrome
There are two types of CRPS:
- Complex Regional Pain Syndrome I (Reflex Sympathetic Dystrophy): Affects 90% of people with CRPS and results from an injury or prolonged period of immobilization.
- Complex Regional Pain Syndrome II (Causalgia): Results from a nerve injury, but pain is not limited to the site of the injury.
The cause of CRPS is unknown; however, in almost every case, the pain originates after an injury or trauma. Potential causes include:
- Prolonged immobilisation, such as being casted
- Burns
- Cuts and bruises
- Sprains
- Surgery, even minor procedures
- Bone breaks and fractures
Symptoms
Regardless of the severity of the initial injury, CRPS symptoms may not present themselves right away. In every case, symptoms include a tingling or burning sensation in the lower and/or upper extremities. The pain may affect the entire leg or arm, or may only influence one toe or finger. Other symptoms include:
- Joint stiffness
- Skin hypersensitivity
- Skin texture change
- Difficulty moving the affected area
- Hair and nail growth pattern disruption
- Muscle atrophy
- Swelling in and around joints
- Decreased range of motion
- Allodynia (pain in the opposite limb)
Diagnosis
There is no clear-cut test to diagnose CRPS. However, your pain management specialist will examine your medical history and may perform an MRI to detect changes in bone or circulation, as well as perform tests to rule out other possible conditions.
Possible Treatments
Treatment options for CRPS often begin with OTC pain relief medication or prescription medications, such as pain relievers, corticosteroids, antidepressants, anticonvulsants, or bone loss medications. Physical therapy, psychotherapy, and biofeedback are additional common treatment options.
Perhaps the most effective treatment option available in the United States is dorsal root ganglion stimulation — a surgical procedure in which a pulse generator with leads attached is placed underneath the skin. The leads send tiny electrical pulses to the dorsal root ganglion, the location in the spinal cord through which every sensory perception must pass, blocking the pain influenced by CRPS.
Other interventional pain management treatments include:
- Sympathetic nerve blocks: A block to the sympathetic nerves is applied via an anaesthetic adjacent to the spine.
- Ketamine IV infusion therapy: Ketamine is given intravenously over a period of several days.
- Surgical sympathectomy: The nerves contributing to CRPS are destroyed.
- Spinal cord stimulation: Electrodes are placed adjacent to the spinal cord.
- Intrathecal pumps: Pain relief medication is sent to the pain site via an implanted catheter or pump.
| Approach | What it involves |
|---|---|
| Physical + occupational therapy | Early, active movement is the cornerstone — the sooner the better |
| Medications | Nerve-pain agents, and bone-targeting drugs in selected cases |
| Sympathetic nerve blocks | Both diagnostic and therapeutic for many patients |
| Spinal cord stimulation | For CRPS that persists despite therapy and blocks |