Muscle tissues

Masseter

• Action: Elevates mandible

• Synergist: Temporalis

• Antagonist: Digastric

Temporalis

• Action: Elevates mandible

• Synergist: Masseter

• Antagonist: Digastric

Digastric

• Action: Depresses mandible

• Synergist: N/A

• Antagonist: Temporalis

Sternohyoid

• Action: Depresses hyoid

• Synergist: Thyrohyoid

• Antagonist: N/A

Sternothyroid

• Action: Depresses thyroid cartilage

• Synergist: N/A

• Antagonist: N/A

Thyrohyoid

• Action: Elevates mandible

• Synergist: Temporalis

• Antagonist: Digastric

Sternocleidomastoid

• Action: Flexes/rotates the head

• Synergist: N/A

• Antagonist: N/A

Clavo-trapezius

• Action: Flexes neck laterally/elevates clavicle

• Synergist: N/A

• Antagonist: N/A

Acromio-trapezius

• Action: Adducts scapula

• Synergist: Rhomboideus

• Antagonist: N/A

Spino-trapezius

• Action: Depresses scapula

• Synergist: Pectoralis minor

• Antagonist: Levator scapulae

Latissimus Dorsi

• Action: Adducts humerus

• Synergist: Pectoralis Major

• Antagonist: Acromio-deltoid

Clavo-deltoid

• Action: Flexes & adducts humerus

• Synergist: Pectoralis Major

• Antagonist: Acromio-deltoid

Acromio-deltoid

• Action: Adducts humerus

• Synergist: Supraspinatus

• Antagonist: Latissimus dorsi

Spino-deltoid

• Action: Extends humerus

• Synergist: Pectoralis major

• Antagonist: N/A

Levator scapulae

• Action: Elevates scapula

• Synergist: Rhomboideus

• Antagonist: Spino-trapezius

Rhomboideus

• Action: Adducts & elevates scapula

• Synergist: Levator scapulae

• Antagonist: Pectoralis major

Subscapularis

• Action: Medial rotation of the humerus

• Synergist: Teres major

• Antagonist: Infraspinatus

Supraspinatus

• Action: Adducts humerus

• Synergist: Acromio-deltoid

• Antagonist: Latissimus dorsi

Infraspinatus

• Action: Lateral rotation of the humerus

• Synergist: N/A

• Antagonist: Teres Major

Teres Major

• Action: Medial rotation of the humerus

• Synergist: Subscapularis

• Antagonist: Infraspinatus

Serratus Anterior

• Action: Anterior rotation of scapula

• Synergist: N/A

• Antagonist: N/A

Pectoralis Minor

• Action: Steadies & depresses scapula

• Synergist: Spino-trapezius

• Antagonist: Levator scapulae

Pectoralis Major

• Action: Flexes & Adducts humerus

• Synergist: Clavo-deltoid

• Antagonist: Acromio-deltoid