A rare anomaly of the abductor digiti minimi muscle of the foot.

One case with anomalous fascicles in the abductor digiti minimi muscle (ADM), noted in the course of dissecting the left lower extremity of a 62-year-old male cadaver, is described. The ADM had proximally three bellies and distally one. One of the proximal bellies presented the normal belly and others were the supernumerary fascicles. Both fascicles arose from the calcaneus, one was inserted into the base of the fifth metatarsal (FMB) and the other into the tuberosity of the fifth metatarsal (FMT). One belly coursing distally arose from the FMB and was inserted into the proximal phalanx of the fifth digit. The normal belly ended in the FMB and also both in the distal belly and in the flexor digiti minimi muscle. One of the supernumerary fascicles (medial fascicle) crossed the lateral plantar artery. To our knowledge, this is an anatomic variation which has never been described before. The morphology of this anomaly is discussed in relation to previously described anomalies of the plantar muscles.