Muscle
Digastric
Two-bellied suprahyoid muscle
High-yield
Two bellies, two nerves - anterior belly by CN V3 (mylohyoid nerve), posterior belly by CN VII.
Overview
A suprahyoid muscle with anterior and posterior bellies (from different pharyngeal arches) that elevates the hyoid and depresses the mandible.
Reference facts
- Origin
- Anterior belly: digastric fossa of the mandible. Posterior belly: mastoid notch of the temporal bone
- Insertion
- Intermediate tendon to the hyoid bone (via a fibrous sling)
- Action
- Elevates the hyoid bone; depresses and retracts the mandible (opens the jaw)
- Innervation
- Anterior belly: mylohyoid nerve (CN V3). Posterior belly: facial nerve (CN VII)
- Blood supply
- Facial / lingual / occipital arteries
Frequently asked questions
What does the digastric do?
The digastric elevates the hyoid bone; depresses and retracts the mandible (opens the jaw).
What nerve innervates the digastric?
Anterior belly: mylohyoid nerve (CN V3). Posterior belly: facial nerve (CN VII).
Where does the digastric attach?
Origin: Anterior belly: digastric fossa of the mandible. Posterior belly: mastoid notch of the temporal bone. Insertion: Intermediate tendon to the hyoid bone (via a fibrous sling).
What is the blood supply of the digastric?
The digastric is supplied by the facial / lingual / occipital arteries.