digastric muscle


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Related to digastric muscle: geniohyoid, Stylohyoid muscle

di·gas·tric mus·cle

(dī-gas'trik mŭs'ĕl)
1. One of the suprahyoid group of muscles consisting of two bellies united by a central tendon that is connected to the body of the hyoid bone; origin, by posterior belly from the digastric groove medial to the mastoid process; insertion, by anterior belly into lower border of mandible near midline; action, elevates the hyoid when mandible is fixed; depresses the mandible when hyoid is fixed; nerve supply, posterior belly from facial, anterior belly by nerve to the mylohyoid from the mandibular division of trigeminal.
2. A muscle with two fleshy bellies separated by a fibrous insertion;
Synonym(s): musculus digastricus [TA] .

digastric muscle

Neck muscle with two bellies. Origin: anterior belly attaches to the digastric fossa in mandible at base of anterior midline, posterior belly attaches to mastoid process. Insertion: tendon connecting both bellies in a loop of fascia that is attached to hyoid bone. Nerve: anterior belly -- trigeminal (CN V), posterior belly -- facial (CN VII). Action: lowers mandible and raises hyoid bone.
See: neck for illus.
See also: muscle
References in periodicals archive ?
In domestic animals such as cats and dogs, the caudal part is located at the occiptomandibular region of the digastric muscle and in close relation with the mandibular gland, which is easily separable after the removal of the common fibrous capsule.
The anterior belly of the digastric muscle originates in the digastric fossa, in the lower interior of the mandible, while the posterior belly originates in the mastoid notch, on the medial side of the mastoid process of the temporal bone.
The digastric muscle is located in the anterior region of the neck and its bellies are the limits of the submandibular (digastric), submental and carotid triangles.
After the isolation of the lingual artery, it was observed in its origin the presence or absence of the linguofacial trunk, the relations with the digastric muscle, the hypoglossal nerve and the hyoid bone, as well as the pathway of the artery in the region of the neck.
It was observed its relations with the neighbour anatomic structures, and in 97,92% of the cases the lingual artery was found inferior to the tendon of digastric muscle, and in 89,58% of the cases was found superior to the hyoid bone.
When the embryo is between 10 and 18 mm in length, the deep layer of the second mesenchymal lamina differentiates into the posterior digastric complex (the stapedius muscle, the posterior belly of the digastric muscle, the digastric tendon, and the stylohyoid muscle).
In the 22-mm embryo (middle of the seventh week), the posterior belly of the digastric muscle and the stapedius and stylohyoid muscles are developing (figure 9).
45) Shirley also commented that young singers often use digastric muscles and a tense jaw to support the tone incorrectly.
The boundaries of the submental space are formed by the hyoid bone inferiorly, the mandible superiorly, and the anterior bellies of the digastric muscles bilaterally (figure).
The most important of these are the masseter and temporalis muscles, which close the jaw, and the digastric muscles, which open the jaw wide.
unusual insertion of the stylohyoid & digastric muscles, an unusual occurrence of levator submandibuli muscle (Banjo muscle), duplicated or other anomalies of omohyoid, anomalous belly of sternothyroid muscle or appearance of levator claviculae muscle (1-6).
5-cm infiltrative left parotid tumor with an extracapsular spread to the adjacent sternocleidomastoid and digastric muscles (figure 1 ).