Gross Anatomy of the Muscular System

Gross Anatomy of the Muscular System
Name Course Instructor Date
Briefly identify, list, and describe the action of the following muscle types: superficial (i.e.,
two anteriors and two posteriors) muscles
Anterolateral neck and throat muscles
* Sternocleidomastoid
* Sternohyoid
Posterior muscles
* Trapezius,
* Splenius cervicis and splenius capitis
For the anterior muscles of the neck, the superficial muscles are sternocleidomastoid and sternohyoid . The ternocleidomastoid causes simultaneous contraction of both muscles of pair causes flexion of the neck forward. It is made up of the clavicular head and sternal head. The “sternocleidomastoid muscle has its origin on the sternum (sterno) and clavicle (cleido) , and inserts on the mastoid process of the temporal bone” (Marieb & Smith, 2016). Sternohyoid‘s origin is the Clavicle and manubrium, while the insertion is the hyoid bone and the action is depressing the hyoid bone and larynx (Marieb & Smith, 2016). The sternohyoid runs most medially along the neck.
For the neck's posterior muscles, there are the superficial layer trapezius, splenius cervicis, and splenius capitis. The trapezius is the superficial muscles of the posterior thorax that helps to keep the spine straight. Their action is extending heads, raising, rotating, and retracting the scapula, and stabilizing them. Splenius cervicis and splenius capitis are two sides that extend the neck, and each rotates and flexes the neck laterally to one side (Martini, Nath & Bartholomew, 2018). Pectoralis major and serratus anterior are superficial anterior muscles of the thorax and shoulder. The pectoralis major covers the upper portion of the chest. This includes the regions with cartilages of ribs 2–6, b, and the muscle's action is arm flexion, adduction, and medial rotation at the shoulder. Serratus anterior is in the anterior and su...