Division of the first dorsal compartment of the hand into two separated canals: rule or exception?

BACKGROUND Tendon entrapment of the first dorsal compartment of the wrist, the de Quervain disease, is a common cause of wrist and hand pain and disability. A group of 50 consecutive patients operated for the treatment of de Quervain disease from 2003 through 2006 were prospectively studied to determine the variation in the pattern of the first extensor compartment. METHODS Eighty-six percent of the patients were females, and 14% were males. In 80% of the cases the nondominant and in 20% the dominant hand was involved. These interesting findings may rule out the occupation's relation to de Quervain disease. RESULTS Our study revealed that the compartment is completely separated into two canals in 86% of the patients which was significantly higher than that reported in similar studies. CONCLUSION The existence of two separated compartments for abductor pollicis longus and extensor pollicis brevis tendons should be considered as a common finding during operation to prevent incomplete treatment and recurrence of the symptoms.