Abstract:

Anatomical variation in submental region especially the digastric muscles are common& its knowledge is important for surgical purpose. The anterior belly of the digastric muscle varies greatly in its shape and size. It is important to know the variation of the digastric muscle, as it is used as a landmark in certain surgical procedures, especially for surgeons operating in the submandibular and submental region. The digastric muscle is formed by two muscle bellies: one anterior and one posterior, joined by an intermediate tendon. It is localized in the anterior cervical region. The anterior belly divides the region between the hyoid bone & the mandible into two, a lateral (submandibular) & a medial (submental triangle).This muscle participates in deglutition & mandibular movements.

30 formalin fixed cadavers were dissected, out of which 28 suprahyoid regions showed a single anterior belly of digastric muscle bilaterally, with an average length of 4.7 cm originating from the digastric fossa of the mandible and had insertions on the intermediate tendon. Anatomical variation in the anterior belly of the digastric muscles was noted in two cadaveric specimens that showed additional muscular strips unilaterally. Knowledge of the variations of the digastric muscle may prevent complications when surgery is performed in the suprahyoid region (anterior region of the neck) or during reporting of imaging techniques of the same as well as when differentiating between cervical masses.

Key Words: Digastric muscle, Anterior belly, Accessory ant. Belly, Variations, Intermediate tendon, Suprahyoid region.

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