Complex Regional Pain Syndrome (CRPS)

Most early or mild cases recover on their own. Treatment is most effective when started early.

Primary therapies that are widely used include:

Rehabilitation and physical therapy. This is the single most important treatment for CRPS. Keeping the painful limb or body part moving improves blood flow and lessens circulatory symptoms, as well as maintains flexibility, strength, and function. Rehabilitating the affected limb helps prevent or reverse secondary spinal cord and brain changes associated with disuse and chronic pain. Occupational therapy can help people learn new ways to become active and return to work and daily tasks.

Psychotherapy. People with severe CRPS often develop secondary psychological problems including depression, situational anxiety, and sometimes post-traumatic stress disorder. These heighten pain perception, further reduce activity and brain function, and make it hard for patients to seek medical care and engage in rehabilitation and recovery. Psychological treatment helps people with CRPS to feel better and better recover from CRPS.

Graded motor imagery. Individuals are taught mental exercises including how to identify left and right painful body parts while looking into a mirror and visualizing moving those painful body parts without actually moving them. This is thought to provide non-painful sensory signals to the brain that helps reverse brain changes that are prolonging CRPS.

Medications. Several classes of medication have been reported as effective for CRPS, particularly when given early in the disease. However, none are approved by the U.S. Food and Drug Administration (FDA) to be marketed specifically for CRPS, and no single drug or combination is guaranteed to be effective in everyone. Drugs often used to treat CRPS include:

• Acetaminophen to reduce pain associated with inflammation and bone and joint involvement.
• Non-steroidal anti-inflammatory drugs (NSAIDS) to treat moderate pain and inflammation, including over-the-counter aspirin, ibuprofen, and naproxen in sufficient doses.
• Drugs proven effective for other neuropathic pain conditions, such as nortriptyline, gabapentin, pregabalin, and duloxetine. Amitriptyline, an older treatment, is effective but causes more side effects than nortriptyline, which is very similar chemically.
• Topical local anesthetic ointments, sprays, or creams such as lidocaine and patches such as fentanyl. These can reduce allodynia, and skin coverage by patches can provide additional protection.
• Bisphosphonates, such as high dose alendronate or intravenous pamidronate, that reduce bone changes.
• Corticosteroids that treat inflammation/swelling and edema, such as prednisolone and methylprednisolone.
• Botulinum toxin injections can help in severe cases, particularly for relaxing contracted muscles and restoring normal hand or foot positions.
• Opioids such as oxycodone, morphine, hydrocodone, and fentanyl may be required for individuals with the most severe pain. However, opioids can convey heightened pain sensitivity and run the risk of dependence.
• N-methyl-D-aspartate (NMDA) receptor antagonists such as dextromethorphan and ketamine are controversial unproven treatments.

Spinal cord stimulation. Stimulating electrodes are threaded through a needle into the spine outside the spinal cord. They create tingling sensations in the painful area that helps block pain sensations and normalize signaling into the spinal cord and brain. Electrodes can be placed temporarily for a few days to assess if stimulation is likely to be helpful. Minor surgery is required to implant the stimulator, battery, and electrodes under the skin on the torso. Once implanted, stimulators can be turned on and off and adjusted with an external controller.

Other types of neural stimulation. Implanted neurostimulation can be delivered at other locations including near injured nerves (peripheral nerve stimulators), under the skull (motor cortex stimulation with electrodes), and within brain pain centers (deep brain stimulation). Recent noninvasive commercially available treatments include nerve stimulation at the peroneal nerve at the knee. Another is repetitive Transcranial Magnetic Stimulation or rTMS, a noninvasive form of brain stimulation that uses a magnetic field to change electrical signaling in the brain. Similar at-home use of small transcranial direct electrical stimulators is also being investigated. These stimulation methods have the advantage of being non-invasive; however, repeated treatment sessions are needed to maintain benefit, so they require time.

Spinal-fluid drug pumps. These implanted devices deliver pain-relieving medications directly into the fluid that bathes the nerve roots and spinal cord. Typically, these are mixtures of opioids, local anesthetic agents, clonidine, and baclofen. The advantage is that very low doses can be used that do not spread beyond the spinal canal to affect other body system. This decreases side effects and increases drug effectiveness.

Alternative and holistic therapies. Based on studies from other painful conditions, some individuals are investigating accessible treatments such as medical marijuana, behavior modification, acupuncture, relaxation techniques (such as biofeedback, progressive muscle relaxation, and guided motion therapy), and chiropractic treatment. These do not benefit the primary cause of CRPS, but some people find them useful. They are generally accessible and not dangerous to try.

Limited use therapy for the most severe or non-resolving pain that has not responded to conventional treatment, such as ketamine. Some investigators report benefit from low doses of ketamine—a strong anesthetic—given intravenously for several days. In certain clinical settings, ketamine has been shown to be useful in treating pain that does not respond well to other treatments. However, it can cause delusions and other symptoms of psychosis with long-lasting impact.

Rarely used former treatments include:

Sympathetic nerve block. Previously, sympathetic blocks—in which an anesthetic is injected next to the spine to directly block the activity of sympathetic nerves and improve blood flow—were used. More recent studies demonstrate no long-lasting benefit after the injected anesthetic wears off and there is the risk of injury from needle injections, so this approach has fallen from favor.

Surgical sympathectomy. This destroys some of the nerves that carry pain signals. Use is controversial; some experts think it is unwarranted and makes CRPS worse, while others report occasional favorable outcome. Sympathectomy should be used only in individuals whose pain is temporarily dramatically relieved by sympathetic nerve blocks.

Cutting injured nerves or nerve roots. People with CRPS often ask if cutting the damaged nerve above the site of injury would end the pain. In fact, this causes a larger nerve lesion that will affect a larger area of the limb. Also, the spinal cord and brain react badly to being deprived of stimulation which can result in central pain syndromes. Other than in exceptional circumstances such as palliative care, this should not be performed.

Amputating the painful lower limb. This is an even more drastic and disabling form of nerve cutting, and the consequences are irreversible, whereas CRPS almost always improves over time, albeit sometimes slowly. Amputation is thus not appropriate for pain control alone, but it is rarely required to manage bone infection or to permit use of a prosthesis for long-affected non-recovering individuals. This last resort should not be performed without input from several specialists along with psychological counseling.