AP1 Muscle Functions Flashcards
Frontalis
raises eyebrows/ wrinkles forehead
Occipitalis
tenses / retracts scalp
Orbicularis Oculi
closes eye
Orbicularis Oris
Closes lips (whistling)
Zygomaticus Major & Minor
Draw corners of mouth upward (smiling)
Platysma
Tenses skin of neck
Masseter
elevates mandible, closes jaw
Temporalis
raises & retracts mandible
Sternocleidomastoid
(Ips): turns head toward shoulders of opposite side
(Bil): neck FLEXION
Quadratus Lumborum
Ips: Lateral FLEXION of trunk
Bil: Lateral stability to vertebral column, stabilizes 12th rib during inspiration
Erector Spinae
Consists of 3 muscles: Iliocostalis, Longissimus, Spinalis
Function: Posture/support spine: laterally FLEXION of spine
Rectus Abdominis
Trunk FLEXION. depresses ribs/ upwardly rotates pelvis
External Oblique
Ips: Trunk ROTATION to opposite side, lateral FLEXION of trunk to same side
Bil: FLEXION of trunk
Internal Oblique
Ips: ROTATION of trunk to same side & lateral FLEXION of trunk to same side.
Bil: FLEXION of trunk
Transversus Abdominis
Compresses abdominal contents
External Intercostals
Elevate rib cage/ Inspiration
Internal Intercostals
Depress rib cage/ exhalation
Diaphragm
contracts to pull central tendon inferior & increase superior-inferior thoracic cavity dimensions
Trapezius
Elevates, depresses, rotates, retracts, stabilizes scapula
Rhomboid Major & Rhomboid Minor
ADDUCTS, stabilizes, rotates scapula downward
Latissimus Dorsi
Extends shoulder joint, ADDUCTS and ROTATES humerus medially, depresses and rotates scapula downward
Pectoralis Major
Flexes shoulder joint, ADDUCTS and rotates humerus medially
Pectoralis Minor
Depresses scapula down (protracts & stabilizes)
Serratus Anterior
Rotates scapula up (stabilizes & protracts)
