Reflex Sympathetic Dystrophy Syndrome (RSDS) Diagnosis
The diagnosis of RSDS is most often made when no other diagnosis can be made. RSDS patients often suffer from other conditions such as fibromyalgia or Chronic Fatigue Syndrome, which can further complicate an accurate diagnosis. The diagnosis should be made on the basis of what the patient feels and what the doctor observes. The doctor may request various laboratory tests or nerve tests but still not be able to make a positive diagnosis. The patient becomes frustrated because they know that they hurt, but their doctor cannot make a definitive diagnosis. It is not uncommon for an RSDS patient to be told that the pain is "in their head." Since this pain is coming from the sympathetic nervous system and the sympathetic nervous system involves emotion, this is one of the worst things that a patient can hear, and can actually make the chronic pain worse.
RSDS is an injury disease. Often, a very small injury can lead to the disease. This injury can be a sprain, strain, or surgery. We have even treated a chronic pain patient who developed RSDS from a bee sting!
While there is no definite time period for the onset of RSDS, the symptoms usually begin within a few weeks of the original injury. Typically, the patient begins complaining of a severe pain and/or a burning sensation, which may or may not be where the injury occurred. Upon examination by the doctor, the patient's toes or fingers are very sensitive and many times a light touch will be felt as a pain. The patient often, but not always, has discoloration in the injured body part. This discoloration is much more apparent when the affected body part is seen against a white background. The injured body part will either be hot or cold, but usually not normal temperature. With time, RSDS creates changes in the blood flow and causes weakening of the bones. If left untreated RSDS can, and usually does, spread to other parts of the body.
Testing for RSDS Symptoms
The doctor can make a diagnosis of RSDS based on the following criteria:
- Altered blood circulation in the toes but normal blood circulation in the foot (measured by photoplethysmography).
- Altered skin coloration documented by dated photographs.
- Changes in bone density (which can be measured by a single phase bone densitometer) and bone structure on x-rays.
- Abnormal sensory nerve testing. (Nerve conduction velocity studies are insufficient since they only test one type of nerve fiber and only decreased function. The Neurometer tests all three major nerve fiber types, as well as, increased or decreased function.)
- Temperature differences between the hands and between the feet.
- Markedly increased reaction to cold temperature.
- Allodynia - Pain due to a stimulus which does not normally provoke pain; such as a burning sensation felt when bedcovers are placed on the feet.
- Nonpruritic Lichenification - A scaling of the foot that does not itch.
