Complex regional pain syndrome, CRPS for short, encompasses a group of symptoms that can include pain, swelling, and stiffness. It usually affects one arm or leg and can even affect just a part of the limb. CRPS often arises after injury, such as a fracture (broken bone) or sprain. It can even arise after surgery. There are two types of CRPS, one associated with nerve injury (Type II CRPS) and one without nerve injury (Type I CRPS). In both types of CRPS, people affected have worse pain than would be expected for the underlying problem.
The exact cause of CRPS is unknown. It is thought that CRPS results from dysfunction in the central and peripheral nervous systems. This leads to an overactive pain response without ongoing injury. CRPS can begin after a minor injury such as a sprain or cut, after major trauma or surgery, or without any known injury. CRPS is three times more likely to occur in women than men. An estimated 60,000 Americans are affected by CRPS.1,2
The key symptom of CRPS is continuous, intense pain. This pain may be out of proportion relative to what is expected for a particular injury or surgery recovery. CRPS most typically starts in one of the arms or legs. Symptoms may include:
The pain may spread to include the entire arm or leg, even though the initiating injury might have been only to a finger or toe. Pain can sometimes even travel to the opposite extremity, but this is uncommon. CRPS may be heightened by emotional stress.
There is no single test to confirm whether someone has CRPS. The diagnosis is made through observation of signs and symptoms. Patients must be seen by a qualified physician who does a thorough history and a physical exam. Other tests like X-rays, MRI or bone scans may show changes to the bones, joints or skin that could be attributed to CRPS. Generally, it is thought that the chance of recovery from CRPS improves the earlier the diagnosis of CRPS is made and treatment is started.
Treatment is varied and depends on both the severity of the symptoms and the duration of the problem. Aerobic conditioning, relief of sleep disorders, and treatment of psychological problems can be helpful. Some patients may have a physical problem that needs to be addressed, such as a compressed or entrapped nerve. Since there is no simple cure for CRPS, treatment is intended to relieve painful symptoms so that patients can resume their normal lives, as well as optimize use of the hand or extremity.
Any of the following may be employed to treat CRPS, often in combination:
Each patient with CRPS responds differently to treatment. Spontaneous improvement occurs in some people. Others may have long-term changes despite treatment. Most doctors believe that early treatment is helpful to limit the disability from CRPS, but even this is not entirely clear. More research is needed to understand the causes and development of CRPS, along with how treatment can alter its course.
© 2018 American Society for Surgery of the Hand
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