Muscle action

Head

Temporomandibular Joint

Depression: Lateral pterygoid, Suprahyoid, Infrahyoid

Elevation: Temporalis, Masseter, Medial pterygoid

Protrusion: Masseter, Lateral pterygoid, Medial pterygoid

Retrusion: Temporalis, Masseter, Digastric

Side to Side: Medial pterygoid, Lateral pterygoid, Masseter, Temporalis

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Spine

Cervical Intervertebral Joints

Flexion: Sternocleidomastoid, Longus colli, Scalenus muscles

Rotation and Lateral Bending: Sternocleidomastoid, Scalenus muscles, Splenius cervicis, Longissimus cervicis, Iliocostalis cervicis, Levator scapulae, Multifidus, Trapezius

Thoracic and Lumbar Intervertebral Joints

Flexion: Rectus abdominis, Psoas major, Internal oblique, External oblique

Extension: Erector spinae, Quadratus lumborum, Multifidus

Rotation and Lateral Bending: Psoas major, Quadratus lumborum, External oblique, Internal oblique, Multifidus, Longissimus thoracis, Iliocostalis thoracis, Rotatores

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Upper Extremity

Scapula

Elevation: Upper trapezius, Levator scapulae

Depression: Latissimus dorsi, Pectoralis major, Pectoralis minor, Lower trapezius

Protraction: Serratus anterior, Pectoralis minor

Retraction: Trapezius (middle), Rhomboids

Upward Rotation: Trapezius (upper and lower), Serratus anterior

Downward Rotation: Rhomboids, Levator scapulae, Pectoralis minor

Shoulder Joint

Flexion: Anterior deltoid, Coracobrachialis, Pectoralis major (clavicular head), Biceps brachii

Extension: Latissimus dorsi, Posterior deltoid, Teres major, Triceps brachii (long head)

Abduction: Middle deltoid, Supraspinatus

Adduction: Pectoralis major, Latissimus dorsi, Teres major

Horizontal Abduction: Posterior deltoid, Infraspinatus, Teres minor

Horizontal Adduction: Anterior deltoid, Pectoralis major

Lateral Rotation: Teres minor, Infraspinatus, Posterior deltoid

Medial Rotation: Subscapularis, Teres major, Pectoralis major, Latissimus dorsi, Anterior deltoid

Elbow Joint

Flexion: Biceps brachii, Brachialis, Brachioradialis

Extension: Triceps brachii, Anconeus

Radioulnar Joint

Supination: Biceps brachii, Supinator

Pronation: Pronator teres, Pronator quadratus

Wrist Joint

Flexion: Flexor carpi radialis, Flexor carpi ulnaris, Palmaris longus

Extension: Extensor carpi radialis longus, Extensor carpi radialis brevis, Extensor carpi ulnaris

Radial Deviation: Extensor carpi radialis longus and brevis, Flexor carpi radialis, Extensor pollicis longus and brevis

Ulnar Deviation: Extensor carpi ulnaris, Flexor carpi ulnaris

Finger Joints

Flexion: Flexor digitorum profundus and superficialis, Flexor digiti minimi (5th digit), Interossei, Lumbricals

Extension: Extensor digitorum communis, Extensor indicis (2nd digit), Extensor digiti minimi (5th digit)

Abduction: Dorsal interossei, Abductor digiti minimi (5th digit)

Adduction: Palmar interossei

Thumb Joint

Flexion: Flexor pollicis longus and brevis, Opponens pollicis

Extension: Extensor pollicis longus and brevis, Abductor pollicis longus

Abduction: Abductor pollicis longus and brevis

Adduction: Adductor pollicis

Opposition: Opponens pollicis, Flexor pollicis brevis, Abductor pollicis brevis, Opponens digiti minimi

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Lower Extremity

Hip Joint

Flexion: Iliopsoas, Sartorius, Rectus femoris, Pectineus

Extension: Gluteus maximus and medius, Semitendinosus, Semimembranosus, Biceps femoris

Abduction: Gluteus medius, Gluteus minimus, Piriformis, Obturator internus, Tensor fasciae latae

Adduction: Adductor magnus, Adductor longus, Adductor brevis, Gracilis

Lateral Rotation: Gluteus maximus, Obturator externus, Obturator internus, Piriformis, Gemelli, Sartorius

Medial Rotation: Tensor fasciae latae, Gluteus medius, Gluteus minimus, Pectineus, Adductor longus

Knee Joint

Flexion: Biceps femoris, Semitendinosus, Semimembranosus, Sartorius

Extension: Rectus femoris, Vastus lateralis, Vastus intermedius, Vastus medialis

Ankle Joint

Plantar Flexion: Tibialis posterior, Gastrocnemius, Soleus, Peroneus longus, Peroneus brevis, Plantaris, Flexor hallucis

Dorsiflexion: Tibialis anterior, Extensor hallucis longus, Extensor digitorum longus, Peroneus tertius

Inversion: Tibialis posterior, Tibialis anterior, Flexor digitorum longus

Eversion: Peroneus longus, Peroneus brevis, Peroneus tertius

Toe Joints

Flexion: Flexor digitorum longus and brevis, Flexor hallucis longus and brevis, Flexor digiti minimi brevis, Quadratus plantae, Lumbricals

Extension: Extensor digitorum longus and brevis, Extensor hallucis longus and brevis, Lumbricals

Abduction: Abductor hallucis, Abductor digiti minimi, Dorsal interossei

Adduction: Adductor hallucis, Plantar interossei