Review Question - QID 863

Complex regional pain syndrome type I (reflex sympathetic dystrophy) is defined as a disease that develops after an initial noxious or painful event which causes the development of pain and dysfunction out of proportion to the event. It sometimes cannot be linked to a specific physiologic process. Hyperesthesias, edema, and/or blood flow changes are prevalent. Type II (synonym for causalgia) has a known identifiable nerve injury. Hypotheses include increased sympathetic tone causes feedback loop, activation of nociceptors to neurons in spinal cord, continued ischemia, re-activation of pain receptors, and possibly unregulated sensitivity of alpha adrenergic receptors.

For treatment, early gentle physiotherapy is recommended for this condition. Aggressive passive range of motion is contraindicated in the early phases because it will provoke pain and inflammation. The primary goal of therapy is to decrease pain and prevent stiffness. Contrast baths can help desensitize and improve blood flow, and TENS (transcutaneous electrical nerve stimulator) has been shown to have a positive outcome on CRPS type II only (those with identifiable nerve lesions). Illustration A shows the basic pathology of this condition.