A complex variation of the digastric muscle: a case report

Abstract

The anterior belly of the digastric muscle varies greatly in its shape and size. It is important to know the variations of the digastric muscle, as it is used as a landmark in certain surgical procedures. A complex variation of the digastric muscles was detected during the routine dissection of a 55-year-old male cadaver. The anterior belly of the digastric muscle on the left side had an accessory bundle, which arose from the anterior part of the intermediate tendon and divided into two parts after a 2-cm course. The superior part coursed toward the mylohyoid raphe and fused with the mylohyoid muscles of both sides. The inferior part travelled parallel to the hyoid bone and fused with the right mylohyoid muscle. Another accessory bundle was found between the origin of the anterior belly of the right digastric muscle and the bifurcation site of the aforementioned bundle. This latter accessory bundle had no attachment to the mylohyoid muscle. Knowledge of the variations of the digastric muscles may prevent complications when surgery is performed in the suprahyoid region or when imaging is interpreted for this region.