Question

which of the following is a large collective group of muscles of the back which perform extension, lateral flexion, and rotation of the spine and/or neck?

a.) erector spinae group
b.) infrahyoid muscles
c.) sternocleidomastoid
d.) splenius group muscles

Explanation:

Identify the key anatomical criteria

• Location: Large collective group of muscles of the back.
• Actions: Extension, lateral flexion, and rotation of the spine and/or neck.

Evaluate the given options

• a.) Erector Spinae Group: A massive muscle group running vertically along the spine (iliocostalis, longissimus, spinalis) that extends, laterally flexes, and rotates the vertebral column.
• b.) Infrahyoid Muscles: Anterior neck muscles involved in depressing the hyoid bone and larynx during swallowing and speech.
• c.) Sternocleidomastoid: An anterior/lateral neck muscle that flexes and rotates the head/neck.
• d.) Splenius Group Muscles: Located in the posterior neck/upper back, primarily acting on the head and neck rather than being a large collective group for the entire spine.

Select the best match

• The Erector Spinae Group is the primary large collective muscle group of the back responsible for these spinal movements.

Answer:

• a.) Erector Spinae Group (Correct answer)
• b.) Infrahyoid Muscles
• c.) Sternocleidomastoid
• d.) Splenius Group Muscles