Head, Neck, Chest, Abdomen, Back and Shoulder Origins + Insertions + Actions

Epicranius Action:

Frontalis – Raise eyebrow

Orbicularis Oculi Action:

Close eye/Squint

Orbicularis Oris Action:

Pucker lips

Buccinator Action:

Pulls in checks

Zygomaticus Action:

Pulls corners of mouth up/Smile

Platysma Action:

Pulls corners of mouth down/Frown

Masseter Action:

Elevation of the mandible

Temporalis Action:

Elevation of the mandible

Sternocleidomastoid Origin:

• Sternum

• Clavicle

Sternocleidomastoid Insertion

• Mastoid process

Sternocleidomastoid Action

• Flexion of the neck

• Opposite rotation of the neck (contralateral)

Pectoralis Major Origin:

• Clavicle

• Sternum

• Ribs 1-7

• External oblique aponeurosis

Pectoralis Major Insertion:

Greater tubercle of humerus

Pectoralis Major Action:

• Flexion at the shoulder

• Medial rotation at the shoulder

• Adduction at the shoulder

Pectoralis Minor Origin:

Ribs 3-5

Pectoralis Minor Insertion:

Coracoid process of scapula

Pectoralis Minor Action:

Depression of the scapula

Serratus Anterior Origin:

Ribs 1-8

Serratus Anterior Insertion:

Vertebral border of the scapula

Serratus Anterior Action:

Protraction of the scapula

Diaphragm Action:

Resting and forced inspiration

External Intercostal Action:

Resting and forced inspiration

Internal Intercostal Action:

Forced expiration

External Oblique Action:

• Flexion of the trunk

• Lateral flexion of the trunk

• Rotation of the trunk

Internal Oblique Action:

• Flexion of the trunk

• Lateral flexion of the trunk

• Rotation of the trunk

Rectus Abdominis Origin:

• Pubic crest

• Pubic symphysis

Rectus Abdominis Insertion:

• Xiphoid process of the sternum

• Costal cartilage 5-7

Rectus Abdominis Action:

• Flexion of the trunk

• Rotation of the trunk

Splenius Capitis Action:

• Extension of the neck

• Same side rotation of the neck (ipsilateral)

Trapezius Action:

• Superior fibers: elevation of the scapula

• Middle fibers: retraction of the scapula

• Inferior fibers: depression of the scapula

Latissimus Dorsi Action:

• Extension at the shoulder

• Adduction at the shoulder

Erector Spinae Action:

Extension of the trunk

Quadratus Lumborum Action:

Extension of the trunk

Rhomboid Major Action:

Retraction of the scapula

Rhomboid Minor Action:

Retraction of the scapula

Levator Scapula Action:

Elevation of the scapula

Teres Major Action:

• Extension at the shoulder

• Adduction at the shoulder

Teres Minor Action:

Lateral rotation at the shoulder

Infraspinatus Action:

Lateral rotation at the shoulder

Supraspinatus Action:

Abduction at the shoulder

Subscapularis Action:

Medial rotation at the shoulder