In a study of an accessory extensor digiti minimi arising from extensor carpi ulnaris in 240 upper limbs, an accessory tendinous slip originating from extensor carpi ulnaris was observed in the tunnel of the 6th compartment at the wrist in 82 (34.2%). The slip inserted into one of several sites on the 5th metacarpal bone, such as on the base with the main tendon (29.6%), on the midportion (2.5%) or on the head (1.7%). The last type of accessory tendinous slip, which was connected with the extensor aponeurosis of the little finger, is the accessory extensor digiti minimi arising from extensor carpi ulnaris described by Kaplan & Spinner (1984).