Muscles Of The Neck

When referring to the human body, the terms flexors, extensors, rotators, and lateral flexors indicate specific muscle groups and their locations in relation to the body's anatomical planes. Flexors are located on the anterior side of the body, extensors on the posterior side, rotators on the lateral side, and lateral flexors refer to muscles located on the lateral side of the body for side bending motions.

Protraction involves the extension of the upper cervical segment and flexion at the lower cervical segment along with the upper thoracic spine. The other options provided do not accurately describe protraction.

Retraction is the act of pulling the head backwards while slightly tucking the chin, involving flexion of the upper cervical segment and extension at the lower cervical and upper thoracic spine. The incorrect answers provided do not accurately describe the concept of retraction.

The trapezius muscle is responsible for tilting the head backwards and elevating the chin. It is not involved in bending the elbow, flexing the foot, or opening and closing the mouth.

The trapezius muscle originates from the base of the skull, ligamentum nuchae, and the spinous processes of vertebrae 7-12, not from the tip of the shoulder blade, front of the hip bone, or sole of the foot.

The trapezius muscle originates from specific points on the clavicle, acromion, spine, and scapula to allow for various movements of the shoulder and upper back.

The trapezius muscle is primarily innervated by the accessory nerve, also known as cranial nerve XI. This nerve plays a key role in controlling the movement of the trapezius muscle.

The sternocleidomastoid muscle is a major neck muscle that attaches to the sternum, clavicle, and mastoid process of the temporal bone. Its primary functions include rotating the head to the opposite side and flexing the neck forward.

The sternocleidomastoid muscle originates from the medial 1/3 of the clavicle and manubrium, not the lateral 2/3. It does not originate from the inferior aspect of the mandible or the spinous processes of C7 and T1 vertebrae.

The sternocleidomastoid muscle inserts into the mastoid process of the temporal bone, allowing for movement of the head and neck.

The sternocleidomastoid muscle is primarily responsible for flexion of the neck, bringing the head forward. While it does have some role in rotation of the neck, it is not its primary action. Extension and lateral flexion of the neck are primarily carried out by other muscles.

The correct nerve supply of sternocleidomastoid is the accessory nerve, also known as cranial nerve XI. It innervates the muscle and helps control its movements.

The correct answer is splenius capitis and splenius cervicis. These are the actual two muscles that make up the splenius group located in the neck and upper back region.

The correct origin of the splenius capitis muscle is from the spinous processes of the third to sixth thoracic vertebrae and the supraspinous ligaments. It is important to understand the precise anatomical origin of this muscle for clinical applications.

The splenius capitis muscle inserts at the mastoid process, which is a prominent projection on the temporal bone located behind the ear. This attachment point allows the muscle to assist in head extension and rotation.

The splenius capitis muscle is responsible for extension, lateral flexion, and rotation of the cervical spine, not for the actions mentioned in the incorrect answers.

The correct insertion point of the splenius cervicis muscle is on the transverse process of C2-3 vertebrae. This muscle plays a role in neck extension and rotation.

The splenius cervicis muscle is responsible for extending the cervical spine, rotating the head to the side, and laterally flexing the neck to the ipsilateral side. The incorrect answers provided do not accurately describe the actions of the splenius cervicis muscle.

When both splenius muscles act together, they primarily extend the head by pulling the skull upwards and backwards.

The platysma is a superficial muscle in the neck that is responsible for various movements of the lower face and neck. It is located just beneath the skin. The sternocleidomastoid, scalene muscles, and semispinalis cervicis are deeper muscles in the neck responsible for different movements and functions.

The platysma muscle originates from the fascia of the infra and supraclavicular regions, not from the deltoid, pectoralis major, or rectus abdominis muscles.

The insertion point of the platysma muscle is located at the base of the mandible, skin of the cheek, lower lip, angle of mouth, and orbicularis iris. These points are crucial for the muscle's function in facial expressions and movements.

The platysma muscle is responsible for depressing the mandible, lowering the lip, and contributing to various facial expressions such as frowning or pulling the corners of the mouth downward.

The platysma muscle is innervated by the cervical branch of the facial nerve, also known as cranial nerve VII. It is not innervated by the hypoglossal nerve, vagus nerve, or trigeminal nerve.

The borders of the anterior neck triangle are defined by the sternocleidomastoid muscle (lateral border), midline of the neck (medial border), and mandible (superior border).

The posterior triangle of the neck is defined by the posterior border of the sternocleidomastoid muscle, the anterior border of the trapezius muscle, and the clavicle. These landmarks help to locate important structures within the triangle for medical professionals.