Complex Regional Pain Syndrome Diagnosis
Because the symptoms of complex regional pain syndrome (CRPS) are common with other medical conditions (swelling, redness, and change in skin temperature and texture could be signs of nothing more than deep bruising), achieving a proper diagnosis can be difficult.
One of the diagnostic conditions common to both reflex sympathetic dystrophy (RSD) and causalgia is a recurring case of swelling, abnormal flow of blood in surface vessels, or sweating in the injured region. If these symptoms accompany chronic pain in an injured region long after the injury should have healed, a patient may be diagnosed with CRPS.
Perhaps the most incriminating aspect of CRPS is the lack of any other condition that might cause the collection of symptoms experienced by the patient. As a result, it is often a diagnosis by exclusion. Patients are usually between the ages of 20 and 35, which helps to rule out age related disorders that might share some of the symptoms. It is also possible for children to develop RDS or causalgia, though it is rarer. Women suffer from the disorder more commonly than men.
There are several tests that may be administered to confirm suspicions of CRPS if a patient meets all of the diagnostic criteria. While none of these tests are absolute confirmation of an occurrence of CRPS, they are helpful in diagnosing patients with chronic pain. Unfortunately, diagnosis in some situations is not possible until after CRPS has set in and begun to spread, making treatment more difficult.
One method of diagnosis, apart from the observation of symptoms, is a bone scan. CRPS can exhibit a slight deterioration of bones around the affected area and the accumulation of calcium in the bloodstream. A bone scan can detect this wear on the bones. A radioactive substance is injected into the veins, making it possible for a specialized camera to view the bone tissue and any potential damage to it.
A second method used to diagnose RSD or causalgia is thermography. This is a sympathetic nervous system test, which measures skin temperature and blood flow. If a significant difference is shown between a healthy and an unhealthy limb, unexplained by any other cause, then the probability of CRPS is greater.
MRI scans and X-rays are also used to detect CRPS, for much the same reasons as bone scans. X-rays may be able to pick up irregularities or mineral loss from bones, while MRI’s can show a number of tissue irregularities. Neither of these depends upon the injection of radioactive material into the body, though X-rays utilize strong radioactive waves and MRI’s use strong magnetism.
Electrodiagnostic tests are another way to determine the likelihood of the presence of CRPS by checking for nerve damage. Electromyography and Nerve Conduction studies are the best ways to determine the extent of nerve damage and are performed with the injection of small needles into muscle groups that send mild electric shocks. These methods are most useful in determining whether a patient has causalgia because of the ability to locate damaged nerves. However, the mild electric shocks used in the procedure may cause more severe pain in a sufferer of causalgia than they would in someone without this condition, leading to some patients opting out of electrodiagnostic testing.