Complex regional pain syndrome

The term causalgia (Greek: kausis – burning, algos – pain) was introduced by Silas Weir Mitchell in 1864. It was used to describe a rare syndrome that followed a minority of partial peripheral nerve injury in the American civil war. Triad: burning pain, autonomic dysfunction and trophic changes.

For causalgia, see Complex regional pain syndrome (CRPS):

CRPS Type II (AKA major causalgia) follows nerve injury (originally described after high velocity missile injuries). CRPS Type I (AKA reflex sympathetic dystrophy or causalgia minor) denoted less severe forms, and has been described after non-penetrating trauma 1).

Shoulder-hand syndrome and Sudeck's atrophy are other variant designations. In 1916, the autonomic nervous system was implicated by René Leriche, and the term reflex sympathetic dystrophy (RSD) later came into use 2) (but RSD may be distinct from causalgia) 3).

Complex regional pain syndrome (CRPS) formerly reflex sympathetic dystrophy (RSD), “causalgia”, or reflex neurovascular dystrophy (RND) is an amplified musculoskeletal pain syndrome (AMPS). It is a chronic systemic disease characterized by severe pain, swelling, and changes in the skin. CRPS often worsens over time. It may initially affect an arm or leg and spread throughout the body; 35% of people report symptoms throughout their whole body.

Other potential effects include: systemic autonomic dysregulation; neurogenic edema; musculoskeletal, endocrine, or dermatological manifestations; and changes in urological or gastrointestinal function.

CRPS is associated with dysregulation of the central nervous system and autonomic nervous system resulting in multiple functional loss, impairment, and disability. The International Association for the Study of Pain has proposed dividing CRPS into two types based on the presence of nerve lesion following the injury.

Type I, formerly known as reflex sympathetic dystrophy (RSD), Sudeck's atrophy, reflex neurovascular dystrophy (RND), or algoneurodystrophy, does not exhibit demonstrable nerve lesions. As the vast majority of patients diagnosed with CRPS have this type, it is most commonly referred to in medical literature as Type I.

Type II, formerly known as causalgia, has evidence of obvious nerve damage. Type II CRPS tends to feature the more painful and difficult-to-control symptomes of CRPS; The Type II disease scores 47 out of 50 on the McGill pain scale[4] (however there are seemingly little or no data pertaining to Type I specifically here). In Type II the “cause” of the syndrome is a known or obvious nerve injury, although the cause of the mechanisms of CRPS Type II are as unknown as the mechanisms of Type I.

The cause of CRPS is unknown. Precipitating factors include injury and surgery, although there are documented cases where no injury had occurred at the original site.[citation needed] CRPS is not caused by psychological factors, yet the constant pain and reduced quality of life has been known to cause psychological problems (such as increased depression and anxiety).

Evidence suggests that CRPS has both physical and psychological factors. Although “research does not reveal support for specific personality or psychopathology predictors of the condition,” CRPS is associated with psychosocial effects, including impaired social and occupational function. In addition, the poor quality of life, for some, has led to high rates of depression and suicide, which has motivated appeals for greater understanding.

Treatment

see Complex regional pain syndrome treatment

1)
Sternschein MJ, Myers SJ, Frewin DB, et al. Causalgia. Arch Phys Med Rehabil. 1975; 56:58–63
2)
Schott GD. An Unsympathetic View of Pain. Lancet. 1995; 345:634–636
3)
Ochoa JL, Verdugo RJ. Reflex Sympathetic Dystrophy: A Common Clinical Avenue for Somatoform Expression. Neurol Clin. 1995; 13:351–363