Complex Regional Pain Disorder

CRPS I is formally known as reflex sympathetic dystrophy, while type II used to be referred to as causalgia.  Both are difficult diseases to diagnose and manage. CRPS I usually follows a minor injury to a specific limb, while type II is usually associated with a partial nerve damage to a peripheral nerve. 


CRPS type I can result from any minor trauma to a limb, including a surgery, infection, a laceration or the application of a cast.  It can also be caused by frostbite, limb infarctions, and degenerative joint disease in a limb.  CRPS type I pain is usually circumferential and does not just involve the distribution of a single nerve, as is seen in type II disease.  The pain is usually burning or aching pain with increased sensitivity to pain, warm , dry or red skin (or cold, blue and sweaty skin) along with some swelling.  The person experiences pain to stimuli not usually considered painful.  Motion of the extremity is reduced and the person can stay this way (in phase I of the disease) or may progress on to phase II or phase III. 

Three to six months after onset of the pain, the person can enter phase II.  The pain is burning and radiates above or below the origin of the original pain.  There is an exquisite sensitivity to temperature or touch and there is decreased hair growth.  The nails may change in character and the joints can become stiff.  There is a certain amount of muscle wasting at this stage.  Contractures or dystonias can occur during this phase of the disease.  Symptoms vary from person to person. 

In the third phase of the disease, the individual has had pain for at least six months. There is decreased skin temperature, atrophy of the skin, smooth glossy skin, fixed joints, contractures, and an increase or decrease in the sweating ability of the skin.  The muscles are severely wasted.  The bone becomes demineralized.  People can get into this phase as early as two to three months post-injury. 


This is caused by direct injury to a peripheral nerve, usually a major proximal nerve.  The pain is described as burning pain by most sufferers and is worse under emotional or environmental stressors.  The pain lasts for at least 5-6 weeks.  It is usually caused by a knife, bullet or sharpened rock injury to a nerve.  When there is a high velocity injury, there are usually shock waves that damage tissue surrounding the place where the initial injury occurred.  The patient often has deep pain along with the burning or stinging pain.  In CRPS type II, there is demineralization of bone as is seen in type I disease, along with fibrosis of the tendon sheathes and muscle spasms. 

Sympathetic Pain

These types of injuries are functions of sympathetic dysfunction and include spontaneous onset of pain, hyperalgesia, tissue swelling, vasomotor disturbances, low motor function, trophic skin changes, and pain relief after the person receives a sympathetic blockade.  Some researchers have used intravenous phentolamine, which acts against the sympathetic nervous system, in order to identify those syndromes that are sympathetic in origin.  Patients have what is called allodynia, which is different from hyperalgesia.  Allodynia is pain that is caused by things that are normally not painful stimuli, while hyperalgesia is the presence of intense pain caused by things that are painful but not as much as would be felt as painful in the average person.  Most patients with CRPS have allodynia rather than hyperalgesia.  Cold and heat hyperalgesia are seen in type I disease but rarely in type II disease.  Mechanical allodynia is seen in both CRPS types I and II; it involves pain to the sensation of touch or other mechanical stimulus.  Mechanical allodynia can be seen in nerve entrapment syndromes and radiculopathies so it is not as specific for CRPS than hot or cold allodynia.  If the symptoms follow  a peripheral nerve, even if it has all the symptoms of CRPS type I, the problem is more likely to be a nerve entrapment syndrome rather than CRPS type I.  CRPS I involves pain all around the limb and not just in the area of a peripheral nerve. 

Treatment of CRPS types I and II

These disorders need psychological intervention as well as medical intervention in order to get better.  Many suffer from depression because of their chronic pain and not the other way around.  Group therapy with other pain patients seems to be helpful in many cases. Family counseling and education also help. 

Pain medications are difficult ways to manage CRPS.  Antidepressants can help the psychological features and some actually seem to help the pain.  Narcotics tend not to work for these types of pain unless they are used to actually block the nerve in injectable form. This has been studied in animals but not in humans as yet.  Sympathetic blocks have been the mainstay of therapy for these patients and it seems to help many.  A sympathetic block tends to warm the arm immediately.  In some cases, the pain Is relieved along with the increased warmth of the skin.  If this occurs, then further sympathetic blocks can be used for symptoms.  The blocks are usually done in a series of 6-10 blocks.  If the blocks work but are temporary, then the patient should have a sympathectomy for relief of their symptoms.  Epidural stimulation has also worked in some cases. 

Other treatments that have been effective in treating CRPS type I include prednisone use, physical therapy, TENS unit therapy, sympathetic blocks or sympathectomy, sympathectomy of the opposite side of the body, epidural pumps, epidural spinal cord stimulators and supportive psychotherapy.  Antidepressants and clonidine have been found to be effective in some cases. 

CRPS is a catastrophic injury and it’s important to contact an experienced attorney experienced in handling this type injury as soon as possible. The Law Offices of Edward A. Smith can help.

Call us at 916.921.6400. Member of Million Dollar Advocates Forum.

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