Anterior muscles:
→ Superficial:
- ① Platysma m.
- O: skin of infra/supraclavicular
- I: → infer. border of mandible → lower lip → angle of mouth
- N: Facial n. (cervical branch)
- F: Depress of the mandible
- B.S: submental + suprascapular a.
- ② Sternocleidomastoid m:
- O: sternum - manubrium + clavicle - sternal part.
- I: mastoid process + nuchal line
- N: accessory nerve + spinal n.
- F: flexion of the head
- B.S: External carotid artery + sup. thyroid art.
→ Suprahyoid muscles: F: elevates the hyoid bone.
- ① Digastric
- O: Ant. belly: digastric fossa of the mandible
- Post. belly: mastoid notch
- I: together by tendon
- N: Ant. belly: mylohyoid
- Post. belly: facial n
- B.S: Submental artery (of the facial art.)
- ② Stylohyoid
- O: styloid process - temporal bone
- I: hyoid bone
- N: Facial n
- B.S: branches of the external carotid artery.
- ③ Mylohyoid m.
- O: mandible - mylohyoid bone.
- I: hyoid bone
- N: mylohyoid n. (mandibular)
- B.S: mylohyoid art.
- ④ Geniohyoid: *
- O: inferior mental spine
- I: hyoid bone
- N: hypoglossal n.
- B.S: Sublingual branch of lingual art.
→ Infrahyoid muscles: F: depress hyoid bone
- ① Sternohyoid
- O: sternum
- I: hyoid bone
- B.S: lingual & superior thyroid art.
- ② Sternothyroid
- O: Sternum
- I: thyroid cartilage
- B.S: Sup. thyroid arts.
- ③ thyrohyoid m.
- O: thyroid cartilage - oblique line
- I: hyoid bone
- B.S: Superior thyroid art. (from External carotid art.)
- ④ Omohyoid m.
- O: Sup. belly: hyoid bone
- Inf. belly: scapula
- I: together by tendon
- B.S: superior thyroid art. + inf. " " (from thyrocervical trunk).
N: Cervical ansa