Complex regional pain syndrome overview

Jump to navigation Jump to search

Complex regional pain syndrome Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Complex Regional Pain Syndrome from other Diseases

Epidemiology and Demographics

Risk Factors

Natural History, Complications and Prognosis

Diagnosis

Diagnostic Criteria

History and Symptoms

Physical Examination

Laboratory Findings

X Ray

Other Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Primary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Complex regional pain syndrome overview On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Complex regional pain syndrome overview

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Complex regional pain syndrome overview

CDC on Complex regional pain syndrome overview

Complex regional pain syndrome overview in the news

Blogs on Complex regional pain syndrome overview

Directions to Hospitals Treating Complex regional pain syndrome

Risk calculators and risk factors for Complex regional pain syndrome overview

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Complex Regional Pain Syndrome (CRPS) is a chronic progressive disease characterized by severe pain, swelling, and changes in the skin. Complex regional pain syndrome (CRPS) is a chronic pain condition that can affect any area of the body, but it often affects an arm or a leg.

It is important to understand that not all complex regional pain syndromes are the same. It is quite possible to have a post-phlebitic syndrome involving the leg that may present with skin color changes, excess pain, and swelling, but has nothing to do with RSD.

The cause of complex regional pain syndrome is currently unknown. Precipitating factors include underlying illnesses (especially vascular disease, an underlying rheumatic condition, a hidden infection or a coagulopathy in RSD cases), orthopedic injury, and surgery. Although there are documented cases that have no identifiable injury to the original site in almost all cases of RSD, there was an underlying event or injury.

Historical Perspective

The condition currently known as Complex regional pain syndrome was originally described by Silas Weir Mitchell during the American Civil War, who named the condition causalgia. In the 1940s, the term reflex sympathetic dystrophy came into use to describe this condition.

Classification

Complex regional pain syndrome has been classified as type I (reflex sympathetic dystrophy with no nerve lesions) and type II (causalgia with obvious nerve damage).

Pathophysiology

Recent research has suggested that oxidative damage (e.g. by free radicals) may play a role in pathophysiology of complex regional pain syndrome. The sympathetic nervous system may also play an important role in the pain. Another theory is that CRPS is caused by a triggering of the immune response

Causes

The cause of complex regional pain syndrome is currently unknown. Precipitating factors include underlying illness (especially vascular disease, an underlying rheumatic condition, a hidden infection or a coagulopathy in RSD cases), orthopedic injury and surgery.

Differentiating Complex Regional Pain Syndrome from other Diseases

Complex regional pain syndrome must be differentiated from shoulder-hand syndrome, Sudeck syndrome, Steinbrocker syndrome and Erythromelalgia.

Epidemiology and Demographics

Complex regional pain syndrome is more common between ages 40- 60, affects women more frequently.

Risk Factors

Precipitating factors for developing complex regional pain syndrome include underlying illness (especially vascular disease, an underlying rheumatic condition, a hidden infection or a coagulopathy in RSD cases), orthopedic injury and surgery.

Natural History, Complications and Prognosis

Good progress can be made in treating complex regional pain syndrome if treatment is begun early which may even result in remission. If treatment is delayed, however, the disorder can quickly spread to the entire limb and changes in bone and muscle may become irreversible.

Diagnosis

Diagnostic Criteria

Both type I and type II varieties of complex regional pain syndrome share common diagnostic criteria of having spontaneous onset of pain not limited to the distribution of a single nerve, a history of edema or abnormal sweating. The only difference lies in the nature of the inciting event.

History and Symptoms

The key symptom of complex regional pain syndrome is intense and burning pain which is much stronger than would be expected for the type of injury that occurred and it gets worse over time. Other symptoms include changes in skin, hair or nails. As disease progresses, there is more edema and there occur irreversible changes in skin and bones.

Laboratory Findings

No specific test is available for complex regional pain syndrome, which is diagnosed primarily through observation of the symptoms. However, thermography, sweat testing, x-rays, electrodiagnostics, and sympathetic blocks can be used to build up a picture of the disorder. Three phase bones scans have been thought of as one of the most specific diagnostic studies for RSD, but they are not very sensitive and therefor delay recognition of cases. A delay in diagnosis and/or treatment for this syndrome can result in severe physical and psychological problems. Early recognition and prompt treatment provide the greatest opportunity for recovery.

X Ray

Patchy osteoporosis can be detected through X-ray as early as two weeks after the onset of CRPS.

Other Imaging Findings

Bone scan can be used to detect osteoporosis sooner than X ray. Bone densitometry is also used to detect changes in bone density and monitor results of treatment.

Other Diagnostic Studies

Thermography is the only test that allows for vasomotor mapping and therefore also provides information as to both the distribution of that patient's complex regional pain syndrome and its underlying generator. It is a diagnostic technique for measuring blood flow by determining the variations in heat emitted from the body. The nerve injury that characterizes type II CRPS can be detected by electromyography.

Treatment

Medical Therapy

The medical therapy of complex regional pain syndrome involves use of a variety of drugs including antidepressants, anti-inflammatories such as corticosteroids and COX-inhibitors such as piroxicam, vasodilators, GABA analogs such gabapentin and pregabalin, and alpha- or beta-adrenergic-blocking compounds. Local anaesthetic like lidocaine is often the first step in treatment. Physical therapy is the most important part of treatment. Implantation of spinal cord stimulators, sympathectomy, EEG feedback, psychotherapy and ketamine are amongst the newer forms of treatment. Surgical, chemical, or radiofrequency sympathectomy can be used as a last resort in patients with impending tissue loss, edema, recurrent infection, or ischemic necrosis suffering from complex regional pain syndrome. There is no prevention at this time for complex regional pain syndrome. Vitamin C has been shown to reduce the prevalence.

References

Template:WH Template:WS