Things to Know Muscle List PDF

# Know the following muscles, their origins, insertions and action ## Muscles: Head | Muscle | Origin | Insertion | Action | |---|---|---|---| | Masseter | Zygomatic arch | Angle of mandible | Elevates mandible (jaw closure) | | Temporalis | Temporal fossa | Coronoid process of mandible | Elevates...

# Know the following muscles, their origins, insertions and action ## Muscles: Head | Muscle | Origin | Insertion | Action | |---|---|---|---| | Masseter | Zygomatic arch | Angle of mandible | Elevates mandible (jaw closure) | | Temporalis | Temporal fossa | Coronoid process of mandible | Elevates mandible | | Buccinator | Maxilla and mandible | Orbicularis oris | Compresses cheek, holds food between teeth during chewing | | Orbicularis oris | muscle fibers associated with lips | Skin at the angle of the mouth | Closes mouth | | Orbicularis oculi | ligaments around orbit | Tissue of the eyelid | Closes eyes | | Depressor anguli oris | Body of the mandible | Skin at angle of the mouth | Draws corner of mouth downward and laterally | | Frontalis | Epicranial aponeurosis | Skin of eyebrows | Raises eyebrows | | Occipitalis | Occipital bone | Epicranial aponeuorosis | Pulls scalp posteriorly | | Zygomaticus major | Zygomatic bone | Skin at the corner of the mouth | Smiling | ## Muscles: Neck | Muscle | Origin | Insertion | Action | |---|---|---|---| | Platysma | Fascia of chest and deltoid | Lower margin of mandible | Tenses skin of neck | | Sternocleidomastoid | Manubrium of sternum | Mastoid process of temporal bone | Forward Flexion of the neck | | Sternohyoid | N/A | N/A | N/A | | Digastric | N/A | N/A | N/A | | Mylohyoid | N/A | N/A | N/A | ## Muscles: Thorax and shoulder: Anterior | Muscle | Origin | Insertion | Action | |---|---|---|---| | Deltoid | Clavicle, Spine of scapula | Deltoid tuberosity of humerus | Abducts arm | | Pectoralis major | Sternum, medial clavicle | Intertubercular sulcus of humerus | Adducts arm | | Pectoralis minor | Ribs 3-5 | Coracoid process of scapula | Depresses the scapula elevates the rib cage | | Serratus anterior | Ribs 1-8 | Scapula medial border | Moves scapula forward | ## Thorax, neck and shoulder: Posterior | Muscle | Origin | Insertion | Action | |---|---|---|---| | Trapezius | Occipital bone, vertebrae C7-T12 | Clavicle (lateral third) Acromion of scapula | Elevates scapula or extends head | | Rhomboid major | Spinous processes of T2-T5 | Medial Border of Scapula | Retracts, adducts and stabilizes the scapula | | Rhomboid minor | Spinous processes of C7-T1 | Medial Border of Scapula | Retracts, adducts and stabilizes the scapula | | Teres major | Posterior surface and the Inferior angle of scapula | Intertubercular sulcus of humerus | Medial rotation of humerus | | Teres minor | Inferior angle of scapula | Greater tubercle of humerus | Lateral rotation of humerus | | Supraspinatus | Supraspinous fossa of Scapula | Greater tubercle of humerus | Stabilizes arm and assists in abduction | | Infraspinatus | Infraspinous fossa of scapula | Greater tubercle of humerus | Adducts and Laterally rotates arm | | Subscapularis | N/A | N/A | Medial rotation | | Latissimus dorsi | Spinous process of T6-L5, iliac crest, ribs 10-12 | Intertubercular sulcus of humerus | Extends arm, adducts and medially rotates arm | ## Deep muscles of the thorax | Muscle | Origin | Insertion | Action | |---|---|---|---| | External intercostal | Inferior border of rib above | Superior border of rib below | Elevates rib cage | | Internal intercostal | Superior border of rib below | Inferior border of rib above | Depresses rib cage | ## Anterolateral of abdominal wall | Muscle | Origin | Insertion | Action | |---|---|---|---| | External oblique | Ribs | Linea alba, pubic crest and tubercles, and iliac crest | Increases abdominal pressure | | Internal oblique | Lumbar fascia, iliac crest | Linea alba, pubic crest | Increases abdominal pressure | | Transversus abdominis | Lumbar fascia, iliac crest | Linea alba, pubic crest | Compresses abdominal contents | | Rectus abdominis | Pubic crest and symphysis | Xiphoid process of sternum | Flexes vertebral column | ## Muscles: Upper Limb | Muscle | Origin | Insertion | Action | |---|---|---|---| | Biceps brachii | Coracoid process of scapula | Radial tuberosity | Supinates forearm Forearm flexion | | Brachialis | Distal humerus | Coronoid process of ulna | Forearm flexion | | Triceps brachii | Posterior humerus | Olecranon process of ulna | Forearm extension | ## Muscles of the forearm and wrist | Muscle | Origin | Insertion | Action | |---|---|---|---| | Brachioradialis | Distal humerus | Styloid process of radius | Forearm extension | | Pronator teres | Medial epicondyle of humerus | Midshaft of radius | Forearm pronation | | Flexor carpi radialis | Medial epicondyle of humerus | Metacarpals II and III | Wrist flexor | | Palmaris longus | Medial epicondyle of humerus | Palmar aponeurosis | Wrist flexor | | Flexor carpi ulnaris | Medial epicondyle of humerus | Hamate, Pisiform and metacarpal V | Wrist flexor | | Flexor digitorum superficialis | Medial epicondyle of humerus | Phalanges 2-5 | Wrist and phalanges flexion | | Flexor digitorum profundus | Coronoid process of ulna | Phalanges 2-5 | Wrist and phalanges flexion | | Extensor carpi radialis longus | Lateral supracondylar ridge of humerus | Metacarpal II | Extension of wrist or abducts wrist | | Extensor carpi radialis brevis | Lateral epicondyle of humerus | Metacarpal III | Extension of wrist or abducts wirst| | Extensor digitorum | Lateral epicondyle of humerus | Phalanges 2-5 | Finger extension | | Extensor carpi ulnaris | Lateral epicondyle of humerus | Metacarpal IV | Extension of wrist | | Supinator | Lateral epicondyle of humerus | Proximal end of radius | Supinates forearm | ## Muscles: Lower Limb | Muscle | Origin | Insertion | Action | |---|---|---|---| | Adductor longus | Pubis | Linea aspera, adductor tubercle | Adducts thigh | | Adductor magnus | Ischial tuberosity, pubic rami | Linea aspera | Adducts thigh | | Gracilis | Pubic rami | Tibia | Medially rotates thigh | | Tensor fasciae latae | Iliac crest | Iliotibial tract | Abducts thigh | | Sartorius | Anterior Superior Iliac Spine | Tibia | Laterally rotates thigh/abduct | ## Quadriceps | Muscle | Origin | Insertion | Action | |---|---|---|---| | Rectus femoris | Anterior Inferior Iliac Spine | Tibial tuberosity, Patella | Extends knee | | Vastus lateralis | Greater trochanter of femur | Tibial tuberosity/Patella | Extends knee | | Vastus medialis | Linea aspera | Tibial tuberosity/Patella | Extends knee | | Muscle | Origin | Insertion | Action | |---|---|---|---| | Gluteus maximus | Ilium | Gluteal tuberosity | Extends thigh | | Gluteus medius | Ilium | Greater trochanter of femur | Abducts thigh | | Muscle | Origin | Insertion | Action | |---|---|---|---| | Biceps femoris | Ischial tuberosity, linea aspera | Head of Fibula | Flexes knee | | Semimembranosus | Ischial tuberosity | Medial condyle of Tibia | Flexes knee | | Semitendinosus | Ischial tuberosity | Tibia | Flexes knee | | Muscle | Origin | Insertion | Action | |---|---|---|---| | Extensor digitorum longus | Lateral condyle of Tibia | Phalanges | Toe extension | | Fibularis longus | Head of Fibula | Metatarsal, Medial Cuneiform | Everts foot | | Fibularis brevis | Fibula | Metatarsal | Plantar flexion of foot | | Soleus | Tibia or fibula | Calcaneus | Plantar flexion of foot | | Gastrocnemius | Medial/lateral condyles of femur | Calcaneus | Plantar flexion of foot | | Tibialis anterior | Lateral Condyle of Tibia | Metatarsal, Medial Cuneiform | Dorsiflexion of the foot |