What is CRPS?
Complex regional pain syndrome is a condition in which patients have chronic pain, typically in the hands, arms, legs, or feet, as a result of trauma or injury. CRPS is thought to be a result of damage to the central or peripheral nervous system. The CNS consists of the spinal cord and brain, while the PNS takes those nerve signals to the rest of the body. With the complex regional pain syndrome disorder, patients experience “prolonged or excessive pain and mild or dramatic changes in skin color, temperature, and/or swelling in the affected area”. CRPS Type 1 (CRPS-I) and CRPS Type 2 (CRPS-II) are the two subcategories of complex regional pain syndrome. CRPS-II used to be called causalgia, and is a classification that was been reserved for patients “with confirmed nerve injuries”. CRPS-I used to be called reflex sympathetic dystrophy syndrome (RSD). It used to be believed that patients “without confirmed nerve injury” have type 1, but research is now starting to show “evidence of nerve injury… so the validity of the two different forms is being investigated”. Though more common in women, anyone at any age can get complex regional pain syndrome, with the average age being 40. This is rare in the elderly and in children before ages 5 or 10, “but it is not uncommon in teenagers”. The most common ways for this condition to develop are soft tissue injury, being in a cast, fractures, sprains, strains, or surgical/medical procedures. The CRPS response is an overreaction to the trauma.1
Prolonged, or even constant, pain that can be severe is the key symptom. It might feel like “pins and needles” or a burning sensation, and it can even feel as if the limb is being squeezed. The injury may start in just a toe or finger, but it can spread to the whole leg or arm, or even to the opposite extremity. The affected area has sensitivity and could be painful even with a light touch. The changes in skin color, temperature, or limb swelling may be constant or intermittent. The nerve damage causes circulation issues. The limb might feel cooler or warmer, and the skin could become red, pale, blue, purple, or blotchy. The skin may appear thin and shiny and it can have an “abnormal sweating pattern” with changes in hair and nail growth. Affected joints are often stiff, and the patient could have “problems coordinating muscle movement”. This may lead to trouble moving the affected part or “abnormal movement” (jerking or dystonia). Patients have peripheral nerve abnormalities, blood vessel and circulation issues, and it impacts the immune system. Diagnosis needs to rule out other conditions, but generally, the “history of earlier injury” helps to determine this disorder. MRI and triple-phase bone scans may be used in diagnosis. For children and teens, the prognosis is good, but some people are left with crippling pain despite any treatment. It is suggested that early treatment helps, at least anecdotally. Treatment options include rehabilitation therapy, psychotherapy, medications, drug pumps, nerve blocks, spinal cord and neural stimulation, and surgery.2
There are many coping strategies available to patients with CRPS/RSD, such as alternative treatments. These are especially useful if patients cannot tolerate or who do not desire medications. Patients can learn about distraction, visualization, biofeedback, meditation, breathing exercises, yoga, stress reduction, and anti-inflammatory diets. Physical and occupational therapy can teach techniques that make daily tasks easier. There are support groups, and service dogs might be an option for some patients.3 Most people have type 1 complex regional pain syndrome. Without treatment, patients could end up with atrophy, or tissue wasting, and contracture, or muscle tightening. Medications include pain relievers, such as aspirin, ibuprofen, or even opioid medications. Anti-depressants and anticonvulsants might also be prescribed, as well as prednisone and other corticosteroids. Bone loss medications, sympathetic nerve-blocking medication, and intravenous ketamine are other prescriptions that could be offered. Patients may benefit from applying cold or heat or using topical analgesics, such as capsaicin cream or lidocaine patches. Physiotherapy, TENS (transcutaneous electrical nerve stimulation), and spinal cord stimulation (electrical current delivered to the spinal cord) can offer pain relief. It is important to maintain as many normal activities as possible, while pacing oneself. Family and friends are important, as are hobbies, since stress can worsen the condition. In terms of prevention, there are some thoughts that “taking vitamin C after a wrist fracture” could lower the risk of developing complex regional pain syndrome. In addition, for stroke patients, “early mobilization” (getting out of bed and walking) is believed to be beneficial in prevention.4 Some other treatment options include hypnosis, relaxation techniques, mirror box therapy, graded motor imagery, tactile discrimination training, Botox injections, sympathectomy (chemical, surgical, or radiofrequency), and even amputation, although the latter is a last resort.5 Patients can benefit from “counseling, psychological support, intervention therapy, and implant therapy”.6