Allodynia - Pain produced by normally non-painful stimulation such as touch, gentle pressure, cold or gentle joint movement.

Analgesia - Pain relief.

Atrophy - Wasting of tissue due to cell degeneration. In CRPS, this may involve skin, subcutaneous tissue, muscle or bone.

Biochemical - Refers to those chemical processes involving human biological function.

Bone scan - A test used to check altered blood flow to bone. A common problem in CRPS. This test becomes positive in 60 percent of CRPS patients.

Carpel Tunnel Syndrome - A constellation of pain, numbness or weakness in the hand due to compression of the median nerve in the wrist. This may be associated with CRPS.

Causalgia - Severe burning pain in association with injury to a nerve.

Cerebral - Pertaining to the major portions of the brain.

Cervical - Pertaining to the bones of the neck (C1-C7), the spinal cord and the nerve roots (C1-C8).

Dystrophy - Progressive changes in tissue often due to loss of nutrition (blood flow).

Drug addiction - A behavior disorder characterized by drug-seeking behavior and the use of drugs for other than medical indications.

Drug dependency - The situation where a patient may come to feel the absolute need for a drug (psychological dependency) or will experience withdrawal symptoms if the drug is taken away (physical dependency).

Edema (swelling) - A visible accumulation of fluid in tissue.

Electro-Muscular Stimulation (EMS) - A technique used to relax muscles or to cause them to contract through the application of electrical current.

Etiology - The cause of a specific illness.

Health care provider - Refers to anyone delivering medical services, including physicians, nurses, chiropractors and physical therapists.

Infrared thermography - A means of measuring heat emission from various parts of the body. Heat emission becomes abnormal at some time in 90% of CRPS patients.

Lesion - A discrete (localized) area of pathology (disease).

Lumbar - Pertaining to the bones of the lower back (L1-L5), nerve roots (L1-L5 and S1) and soft tissues (e.g., muscles, tendons, ligaments, joints) in this area. Note the spinal cord is not included here because it ends at the L1 or vertebral body.

Multidisciplinary - Refers to the delivery of medical services by a team of different medical specialists (e.g., physician, nurse, psychologist, physical therapist).

Nerve blocks - A technique to create anesthesia, or pain relief, in a nerve or nerve root by temporarily interfering with its function. There are other techniques that also create reversible changes to nerves (e.g., radio frequency stimulation), resulting in longer periods of pain relief than is possible with local anesthetics. Irreversible blocks done with surgery or chemicals, called nerve ablation, is listed as a neurectomy or rhizotomy. When any part of the sympathetic nervous system is blocked, the technique is called a sympathetic block (temporary) or sympathectomy (permanent.)

Osteoporosis - Thinning (demineralization) of bone.

Pathology - Organ disease identified by structural change in tissue.

Placebo effect - The situation where a patient gets a good response to a treatment intervention that is unexpected and not easily explained. The placebo effect is inherent in all medical treatment and may simply reflect the body's ability to respond favorable if both the patient and the doctor believe a treatment or procedure is going to work.  While the response mechanism is unknown, it is not imaginary.

Selective Tissue Conductance (STC) - A very specialized test of sympathetic activity in the body. This is generally unavailable.

Syndrome - A combination of recognizable signs and symptoms that form a distinct clinical picture, as opposed to a recognizable disease (e.g., CRPS is a syndrome, while diabetes is a disease).

Thoracic - Pertaining to the bones of the thoracic (T1-T12), spinal cord, and nerve roots (T1-T12), along with the organs of the chest cavity (e.g., lungs).

Transcutaneous Electrical Stimulation (TENS) - A technique used to deliver electrical current to the body.  This is generally done using battery operated generators connected to pads applied to the skin.

Vertebral - The major bones of the spine.

Drug types used in CRPS treatment

Analgesics - Any drug that reduces pain.

Anti-arrhythmics - Drugs with similarities to local anesthetics. These are rarely used and have significant side effects.

Anti-depressants - A class of drugs that may reduce neuropathic or central pain as well as help depression and sleep disturbance.

Anti-epileptic drugs - All share the ability to induce electrical activity in nerve cells. These are often the drugs of choice for neuropathic or central pain (e.g., Neurontin, Topamax, Lyrica).

Local anesthetics - Used for nerve blocks and/or reduction in regional pain. These can be taken orally, intravenously or transdermally (skin patches).

Muscle relaxants - Drugs that reduce pain from muscle spasms. They may cause drowsiness.

Narcotics - A class of drugs that act like morphine in reducing pain.

Non-Steroidal Anti-inflammatory Drugs (NSAIDs) - A class of drugs that inhibit inflammation (e.g., aspirin, ibuprofen, Celebrex) but are not steroids (such as prednisone).

Sedatives, tranquilizers and anti-anxiety drugs - A large class of drugs sometimes used for the treatment of emotional problems associated with pain.

Selective Seratonin Re-uptake Inhibitors (SSRIs) - Used both as antidepressants and as analgesics (e.g., Prozac).

Nervous System Divisions

Autonomic nervous system - Those nerves and nerve chains in the body that supply blood vessels, sweat glands and visceral organs such as the heart. The autonomic nervous system has two divisions: sympathetic and para-sympathetic. The former may become abnormally involved in CRPS (thus the old term reflex sympathetic dystrophy).

Central nervous system - The brain and spinal cord.

Peripheral nervous system - All nerve roots and nerves (motor and sensory) that supply the muscles of the body and transmit information about sensation (including pain) to the central nervous system.

Pain Types

Central pain - Pain associated with injuries or changes in functions in the spinal cord and/or brain.

Chronic pain - Constant pain that either persists beyond an obvious injury and/or is associated with an ongoing painful condition (e.g., cancer, arthritis).

Intractable pain - Pain that is resistant to treatment.

Neuropathic pain - Pain that is associated with demonstratable nerve and/or central nervous system changes.

Nociceptive pain - A normal and expected pain response to injury.