Causalgia: a meta-analysis of the literature.

BACKGROUND

Causalgia is not familiar to most physicians whose training and experience are limited to civilian practice.

HYPOTHESIS

Through a thorough review of the literature, we attempted to determine the boundaries of causalgia and separate it from other sympathetically related disorders.

DATA SOURCES

Database search for English-language articles in MEDLINE and Index Medicus up to the year 2000 as both keyword and subject under causalgia.

STUDY SELECTION

References that described any new cases referred to as "causalgia" by their authors were included in a meta-analysis.

DATA SYNTHESIS

One hundred ten articles contained a total of 1528 cases of causalgia. High-velocity missiles caused at least 77% of the injuries. In 72% and 90% of the cases reported, the time from injury to onset of pain was within 1 week and 1 month, respectively. Median nerve alone or in combination with other nerves (56%) and sciatic trunk injury (60%) were the most common nerves involved. In 92%, the nerve injury was incomplete. The most prominent clinical manifestations included burning pain in 86%, increased sweating in 73%, relief with application of cold in 62%, warmth in 50%, paresthesias in 96%, absence of anesthesia in 81%, and sensitivity to stimuli in 98%. Response to sympathetic blocks was observed in 88%. Finally, a total of 94% of the patients undergoing sympathectomy were cured.

CONCLUSIONS

Cases of causalgia are easy to recognize and treat, with excellent results. Causalgia always follows a somatic nerve injury, usually partial, and is associated with near-constant, very severe pain distal to the injury in the extremity, varied in nature but characteristically with a predominantly burning quality. An effective anesthetic block of the appropriate part of the sympathetic chain frequently immediately relieves the pain. Most cases are cured by surgical sympathectomy.