Anatomy: Muscular System Origins, Insertions, and Actions

Vocabulary practice flashcards detailing muscle origins, insertions, and primary movements across the head, neck, eye, mastication, respiration, abdominal wall, and back regions.

Epicranius: frontalis

Origin: epicranial aponeurosis. Insertion: skin of eyebrows. Primary Movement: raises eyebrows.

Epicranius: occipitalis

Origin: occipital and temporal bones. Insertion: epicranial aponeurosis. Primary Movement: pulls scalp posteriorly.

Orbicularis oculi

Origin: frontal and maxillary bones. Insertion: tissue of eyelid. Primary Movement: closes eyelid.

Levator palpebrae superioris

Origin: lesser wing of sphenoid bone. Insertion: skin of upper eyelid. Primary Movement: opens upper eyelid.

Corrugator supercilii

Origin: arch of frontal bone. Insertion: skin of eyebrow. Primary Movement: draws eyebrows together and inferiorly (frown).

Orbicularis oris

Origin: maxilla and mandible. Insertion: encircles mouth. Primary Movement: closes lips (kissing).

Zygomaticus major

Origin: zygomatic bone. Insertion: skin and muscle at corner of mouth. Primary Movement: raises corner of mouth upwards (smiling).

Buccinator

Origin: molar region of maxilla and mandible. Insertion: orbicularis oris. Primary Movement: whistling & trumping.

Platysma

Origin: fascia of chest. Insertion: mandible. Primary Movement: tenses skin of neck (growling/pouting).

Superior rectus

Extrinsic eye muscle. Primary Movement: elevates eye and turns it medially.

Inferior rectus

Extrinsic eye muscle. Primary Movement: depresses eye and turns it medially.

Medial rectus

Extrinsic eye muscle. Primary Movement: moves eye medially.

Lateral rectus

Extrinsic eye muscle. Primary Movement: moves eye laterally.

Superior oblique

Extrinsic eye muscle. Primary Movement: depresses eye and turns it laterally.

Inferior oblique

Extrinsic eye muscle. Primary Movement: elevates eye and turns it laterally.

Temporalis

Origin: temporal fossa of temporal bone. Insertion: coronoid process of mandible. Primary Movement: closes jaw.

Masseter

Origin: zygomatic arch and zygomatic bone. Insertion: angle and ramus of mandible. Primary Movement: prime mover of jaw closure (chewing).

Pterygoids: medial

Origin: sphenoid, palatine, and maxillary bones. Insertion: mandible. Primary Movement: aids in grinding movements of teeth.

Pterygoids: lateral

Origin: greater wing of sphenoid bone. Insertion: condylar process of mandible. Primary Movement: aids in grinding movements of teeth.

Tongue

Muscle involved in chewing and swallowing. Primary Movement: speaking and chewing.

Sternocleidomastoid

Origin: manubrium of sternum and clavicle. Insertion: mastoid process of temporal bone & occipital bone. Primary Movement: flexes and laterally rotates head.

Splenius capitis

Origin: vertebra. Insertion: mastoid process. Primary Movement: extend or hyperextend head.

Diaphragm

Muscle of respiration. Primary Movement: prime mover of inspiration.

Intercostals (external)

Origin: inferior border of rib above. Insertion: superior border of rib below. Primary Movement: elevates rib cage.

Intercostals (internal)

Origin: superior border of rib below. Insertion: inferior border of rib above. Primary Movement: depresses rib cage.

Scalenes

Origin: transverse processes of cervical vertebrae. Insertion: ribs 1-2. Primary Movement: elevates ribs 1-2 (aid in inspiration).

External oblique

Origin: lower 8 ribs. Insertion: linea alba & iliac crest. Primary Movement: flex spine, rotate trunk, flex laterally, compress viscera.

Internal oblique

Origin: lumbar fascia, iliac crest. Insertion: linea alba & costal cartilage of lower ribs. Primary Movement: flex spine, rotate trunk, flex laterally, compress viscera.

Transverse abdominus

Origin: iliac crest, costal cartilage of lower ribs, & lumbar fascia. Insertion: linea alba. Primary Movement: compresses abdominal contents.

Rectus abdominis

Origin: pubic symphysis. Insertion: xiphoid process & costal cartilage of ribs. Primary Movement: flexes and rotates vertebral column (sit-ups).

Erector spinae

Origin: iliac crest, transverse processes of vertebrae. Insertion: ribs & transverse processes of vertebrae. Primary Movement: prime mover of spine extension.

Quadratus lumborum

Origin: iliac crest and lumbar fascia. Insertion: inferior border of rib 12 and transverse processes of lumbar vertebrae. Primary Movement: flexes vertebral column laterally; core muscle that forms most of posterior abdominal wall and is most often 'pulled'.