Reflex Sympathetic Dystrophy
by Lisa Pavese, FNP, Tory McJunkin, MD, and Paul Lynch, MD.
Reflex sympathetic dystrophy (RSD) is also referred to as Complex Regional Pain Syndrome (CRPS), and typically occurs in the upper or lower extremities. There are two types of CRPS: CRPS 1, when pain stems from an initial painful event that may or may not be traumatic, and CRPS 2, when pain stems from an identifiable painful event or nerve injury. Both CRPS 1 and CRPS 2 cause continuous, intense pain out of proportion to the severity of the injury. Some common symptoms include drastic changes in the temperature and color of the skin over the affected limb or body part, accompanied by severe burning pain, skin sensitivity, sweating, and swelling. Some other key features of CRPS include hyperalgesia (increased sensitivity to painful stimuli), and allodynia (a painful response to a typically non-painful stimulus).
Reflex Sympathetic Dystrophy Diagnosis
Reflex Sympathetic Dystrophy is a very complex pain disorder, which can be very difficult to treat. Reflex Sympathetic Dystrophy often begins in the hand or the foot, and spreads to the affected arm or leg. CRPS can also spread to the opposite arm or leg. The cause of Reflex Sympathetic Dystrophy is still unclear, however, there are several theories. Some theorize that Reflex Sympathetic Dystrophyis maintained by the sympathetic nervous system. Another theory is that CRPS is caused by an immune response, which leads to the inflammatory symptoms of redness, warmth, and swelling in the affected area. There are no specific tests to diagnose CRPS, but testing can be done to rule out other diagnoses that may explain the symptoms. Blood testing can be done to rule out other inflammatory or rheumatologic conditions. Nerve conduction studies can be done to rule out peripheral neuropathy, or nerve entrapment conditions. Magnetic resonance imaging (MRI) can be done to rule out any soft tissue causes for the patient’s neuropathic symptoms. The diagnosis of CRPS is made in the absence of these other possible causes for the patient’s pain.
Reflex Sympathetic Dystrophy Treatment
The typical treatment for CRPS includes nerve blocks for pain reduction, desensitization treatments with a physical therapist, and medications that help with neuropathic pain. Some nerve blocks for upper extremity pain include stellate ganglion blocks, cervical epidural steroid injections, and interscalene blocks, followed by desensitization. Injections for lower extremity CRPS include lumbar sympathetic nerve blocks, lumbar epidural steroid injections, and femoral sciatic nerve blocks, followed by desensitization. Some medications used for CRPS include gabapentin, pregabalin (Lyrica), duloxetine (Cymbalta), and amitriptyline. If the patient does not respond to more conservative treatments, neuromodulation through spinal cord stimulation may be considered. Spinal cord stimulation involves small electrodes placed within the epidural space of the spine. The theory behind spinal cord stimulation is that stimulation of the large nerve fibers will inhibit the small nerve fibers, thus blocking the sensation of pain. Peripheral nerve stimulation is very similar to spinal cord stimulation, but the electrodes are placed along the peripheral nerves, typically close to the area of pain. Spinal cord stimulation has been a very efficacious treatment modality for over 30 years. A study by Forouzanfar and Kemler, et al (2003) indicates that spinal cord stimulation between 42 and 47 percent pain relief to persons suffering from CRPS of the upper and lower extremities. CRPS is a very complex pain disorder, which can be very difficult to treat. The physicians at Arizona Pain Specialists incorporate cutting edge biomedical technologies, along with more conservative treatment modalities, to provide a comprehensive approach to your pain. Call us today to schedule an appointment!
Farouzanfar, T., Kemler, M., and Weber, W., et al (2004). Spinal Cord Stimulation in Complex Regional Pain Syndrome: Cervical and Lumbar Devices are Comparably Effective. British Journal of Anaesthesia, 2004. Kim, Philip (2004). Advanced Pain Management Techniques: An Overview of Neurostimulation. Retrieved February 16, 2010 from: http://www.medscape.com/viewarticle/473431 National Institute of Neurologic Disorders and Stroke (2009). NINDS Complex Regional Pain Syndrome Information Page. Retrieved December 4, 2009 from: http://www.ninds.nih.gov/disorders/reflex_sympathetic_dystrophy/reflex_sympathetic_dystrophy.htm Rho R., Brewer R., and Lamer T., et al. (2002). Complex Regional Pain Syndrome. Mayo Clinic Proceedings, 2002; 77: 174-180.