Complex regional pain syndrome
Complex regional pain syndrome (CRPS) is a form of chronic pain that usually affects an arm or a leg. CRPS typically develops after an injury, a surgery, a stroke or a heart attack. The pain is out of proportion to the severity of the initial injury.
CRPS is uncommon, and its cause isn’t clearly understood. Treatment is most effective when started early. In such cases, improvement and even remission are possible.
The cause of CRPS isn’t completely understood. It’s thought to be caused by an injury to or difference in the peripheral and central nervous systems. CRPS typically occurs as a result of a trauma or an injury.
CRPS occurs in two types, with similar signs and symptoms, but different causes:
Signs and symptoms of CRPS include:
- Continuous burning or throbbing pain, usually in the arm, leg, hand or foot
- Sensitivity to touch or cold
- Swelling of the painful area
- Changes in skin temperature — alternating between sweaty and cold
- Changes in skin color, ranging from white and blotchy to red or blue
- Changes in skin texture, which may become tender, thin or shiny in the affected area
- Changes in hair and nail growth
- Joint stiffness, swelling and damage
- Muscle spasms, tremors and weakness (atrophy)
- Decreased ability to move the affected body part
Doctors use various medications to treat the symptoms of CRPS.
Pain relievers. Pain relievers available without a prescription — such as aspirin, ibuprofen (Advil, Motrin IB, others) and naproxen sodium (Aleve) — may ease mild pain and inflammation.
Your doctor may prescribe stronger pain relievers if OTC ones aren’t helpful. Opioid medications might be an option. Taken in low doses, they might help control pain.
- Antidepressants and anticonvulsants. Sometimes antidepressants, such as amitriptyline, and anticonvulsants, such as gabapentin (Gralise, Neurontin), are used to treat pain that originates from a damaged nerve (neuropathic pain).
- Corticosteroids. Steroid medications, such as prednisone, may reduce inflammation and improve mobility in the affected limb.
- Bone-loss medications. Your provider may suggest medications to prevent or stall bone loss, such as alendronate (Binosto, Fosamax) and calcitonin (Miacalcin).
- Sympathetic nerve-blocking medication. Injection of an anesthetic to block pain fibers in the affected nerves may relieve pain in some people.
- Intravenous ketamine. Some studies show that low doses of intravenous ketamine, a strong anesthetic, may substantially alleviate pain.
- Medicines to lower blood pressure. Sometimes high blood pressure medications, including prazosin (Minipress), phenoxybenzamine (Dibenzyline) and clonidine can help to control pain.
- Heat therapy. Applying heat may offer relief of swelling and discomfort on skin that feels cool.
- Topical analgesics. Various topical treatments are available that may reduce hypersensitivity, such as capsaicin cream available without a prescription, or lidocaine cream or patches (Lidoderm, ZTlido, others).
- Physical or occupational therapy. Gentle, guided exercising of the affected limbs or modifying daily activities might help decrease pain and improve range of motion and strength. The earlier the disease is diagnosed, the more effective exercises might be.
- Mirror therapy. This type of therapy uses a mirror to help trick the brain. Sitting before a mirror or mirror box, you move the healthy limb so that the brain perceives it as the limb that is affected by CRPS. Research shows that this type of therapy might help improve function and reduce pain for those with CRPS.
- Transcutaneous electrical nerve stimulation (TENS). Chronic pain is sometimes eased by applying electrical impulses to nerve endings.
- Biofeedback. In some cases, learning biofeedback techniques may help. In biofeedback, you learn to become more aware of your body so that you can relax your body and relieve pain.
- Spinal cord stimulation. Your provider inserts tiny electrodes along your spinal cord. A small electrical current delivered to the spinal cord results in pain relief.
- Intrathecal drug pumps. In this therapy, medications that relieve pain are pumped into the spinal cord fluid.
- Acupuncture. The insertion of long, thin needles may help stimulate nerves, muscles and connective tissue to increase blood flow and relieve pain.