Multiple variations in the region of Mm. extensores carpi radialis longus and brevis.
While dissecting the body of an 80-year-old female we observed multiple variations in the right region of Mm. extensores carpi radialis longus and brevis. The M. extensor carpi radialis longus gave origin to an accessory head. The tendon of this accessory head passed through a separate tunnel in the extensor retinaculum and inserted in the middle of the first metacarpal bone. Concerning its function, this accessory head of the M. extensor carpi radialis longus could be regarded as an additional abductor pollicis. The M. extensor carpi radialis brevis had an accessory tendon lying underneath the main tendon of this muscle. The accessory tendon joined with the main tendon just when undercrossing Mm. abductor pollicis longus and extensor pollicis brevis. Afterwards the tendon lay in the second tunnel of the extensor retinaculum and inserted in the base of the third metacarpal. In her lifetime the individual's tabatière probably must have been conspicuously pronounced at its radial margin.
Claassen
Horst
H
Institut für Anatomie, Universität Rostock, Germany. horst.claassen@med.uni-rostock.de
Wree
Andreas
A
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D018482:Muscle, Skeletal / Q000002:abnormalities* / Q000033:anatomy & histology*