Gross Anatomy Practical UE

Platysma Origin

Fascia over pectoralis major and deltoid muscles

Platysma Insertion

Mandible, Subcutaneous tissue and skin of lower face, Blends with muscles around the mouth

Platysma Action

Depress mandible, Depress lower lip and corner of mouth, Tensing of skin of neck

Platysma Innervation

Facial n (CN VII)

Sternocleidomastoid Origin

Sternal: Manubrium of sternum Clavicular: Medial clavicle

Sternocleidomastoid Insertion

Mastoid process of the temporal bone

Sternocleidomastoid Action

Unilaterally: Laterally flex the head and neck to the same side, and rotate the head and neck to the opposite side. Bilaterally: Flex the neck and extend the head.

Sternocleidomastoid Innervation

Spinal Accessory n (CN XI) (motor) C2-3 spinal ns (sensory)

Supraspinatus Origin

Supraspinous fossa of scapula

Supraspinatus Insertion

Greater tubercle of humerus (superior facet)

Supraspinatus Action

Abduction, Scaption of humerus, Stabilization of head of humerus

Supraspinatus Innervation

Suprascapular n (C4-6)

Infraspinatus Origin

Infraspinous fossa of scapula

Infraspinatus Insertion

Greater tubercle of humerus (middle facet)

Infraspinatus Action

Lateral rotation, Extension of humerus, Scaption of humerus

Infraspinatus Innervation

Suprascapular n (C5-6)

Teres Minor Origin

Upper 2/3 of axillary border of the scapula

Teres Minor Insertion

Greater tubercle of humerus (inferior facet)

Teres Minor Action

Lateral rotation, Extension of humerus

Teres Minor Innervation

Axillary n (C5-6)

Teres Major Origin

Inferior angle of scapula (dorsal surface), Lower 1/3 of axillary border of scapula

Teres Major Insertion

Medial lip of bicipital groove of humerus

Teres Major Action

Extension, Medial rotation, Adduction of humerus

Teres Major Innervation

Lower subscapular n (C5-6)

Deltoid Origin

Anterior: Lateral 1/3 of clavicle Middle: Lateral surface of acromionPosterior: Spine of scapula

Deltoid Insertion

Deltoid tuberosity of humerus

Deltoid Action

Anterior fibers: Flex, IR, Horizontal adduction of shoulder, Scaption of humerus Middle fibers: ABduction & Scaption of humerus Posterior fibers: Extend, ER, Horizontal abduction of shoulder, Scaption of humerus

Deltoid Innervation

Axillary n (C5-6)

Pectoralis Major Origin

Clavicular head: Medial half of clavicle Sternocostal head: Sternum, Cartilage of upper 6 ribs, Aponeurosis of external oblique muscle

Pectoralis Major Insertion

Lateral lip of biciptal (intertubercular) groove of humerus

Pectoralis Major Action

Adduction, Horizontal adduction, Medial rotation of humerus Clavicular head: Flexion of humerus Sternocostal head: Extension of humerus from a flexed position

Pectoralis Major Innervation

Clavicular head: Lateral & Medial Pectoral ns (C5-6) Sternocostal head: Medial Pectoral n (C8-T1)

Serratus Anterior Origin

Lateral surface of upper 8 ribs (by finger-like slips)

Serratus Anterior Insertion

Vertebral border of scapula - anterior surface

Serratus Anterior Action

Abduction (protraction), Lateral (upward) rotation of scapula, Stabilizes scapula against chest wall, Depression of scapula (lower fibers), Assists forced exhalation; Posterior tilt, External Rotation of Scapula

Serratus Anterior Innervation

Long Thoracic n (C5-7)

Tricep Brachii Origin

Long head: Infraglenoid tubercle of scapula Lateral head: Posterior humerus above spiral groove Medial head: Posterior humerus below spiral groove

Tricep Brachii Insertion

Olecranon process of ulna

Tricep Brachii Action

Extension of elbow, Long head: extension of humerus

Tricep Brachii Innervation

Radial n (C6, 7, 8)

Pectoralis Minor Origin

Anterior surfaces of ribs 3,4,5 near costal cartilages

Pectoralis Minor Insertion

Coracoid process of scapula (medial border of superior surface)

Pectoralis Minor Action

Abduction (protraction), Depression, Medial (downward) rotation, Anterior tilt of scapula, Assists forced inhalation

Pectoralis Minor Innervation

Medial Pectoral n (C8-T1)

Subclavius Origin

1st rib costocartilage junction

Subclavius Insertion

Inferior shaft of clavicle - middle 1/3

Subclavius Action

Depresses clavicle, Stabilizes sternoclavicular joint; Assist depression of scapula

Subclavius Innervation

Subclavian n (C5-6)

Sternohyoid Origin

Manubrium of sternum, Medial clavicle.

Sternohyoid Insertion

Hyoid bone

Sternohyoid Action

Stabilization of hyoid bone in swallowing and speaking by pulling hyoid bone downward. Depression of mandible when hyoid bone is stable.

Sternohyoid Innervation

C1-3 Spinal ns - branches of ansa cervicalis of cervical plexus

Thyrohyoid Origin

Thyroid cartilage

Thyrohyoid Insertion

Hyoid bone

Thyrohyoid Action

Stabilization of hyoid bone in swallowing and speaking by pulling hyoid bone downward. Depression of mandible when hyoid bone is stable.

Thyrohyoid Innervation

C1-3 Spinal ns - branches of ansa cervicalis of cervical plexus

Mylohyoid Origin

Mandible

Mylohyoid Insertion

Hyoid bone

Mylohyoid Action

Elevation of hyoid bone and larynx in swallowing and speaking when mandible is stable. Depression of mandible when hyoid bone is stable.

Mylohyoid Innervation

Trigeminal n (CN V)

Stylohyoid Origin

Mandible, Styloid process of temporal bone

Stylohyoid Insertion

Hyoid bone

Stylohyoid Action

Elevation of hyoid bone and larynx in swallowing and speaking when mandible is stable. Depression of mandible when hyoid bone is stable.

Stylohyoid Innervation

Facial n (CN VII)

Coracobrachialis Origin

Coracoid process of scapula

Coracobrachialis Insertion

Middle 1/3 of medial surface of humeral shaft

Coracobrachialis Action

Flexion, Adduction, Horizontal Adduction of humerus

Coracobrachialis Innervation

Musculocutaneous n (C5,6,7)

Biceps Brachii Origin

Short head: Coracoid process of scapula Long head: Supraglenoid tubercle of scapula

Biceps Brachii Insertion

Tuberosity of radius, Bicipital aponeurosis

Biceps Brachii Action

Flexion of elbow, Supination of forearm, flexion of humerus

Biceps Brachii Innervation

Musculocutaneous n (C5-6)

Subscapularis Origin

Subscapular fossa of scapula

Subscapularis Insertion

Lesser tubercle of humerus

Subscapularis Action

Medial rotation, Adduction of humerus, Scaption of humerus

Subscapularis Innervation

Upper and lower subscapular ns (C5,6,7)

Pronator Teres Origin

Humeral head: Medial epicondyle of humerus Ulnar head: Coronoid process of ulna

Pronator Teres Insertion

Middle of lateral shaft of radius

Pronator Teres Action

Pronation of forearm, Assists in flexion of elbow

Pronator Teres Innervation

Median n (C6-7)

Flexor Carpi Radialis Origin

Medial epicondyle of humerus (common flexor tendon)

Flexor Carpi Radialis Insertion

Bases of 2nd & 3rd metacarpals

Flexor Carpi Radialis Action

Flexion, Abduction of wrist (radial deviation)

Flexor Carpi Radialis Innervation

Median n (C6, 7)

Palmaris Longus Origin

Medial epicondyle of humerus (common flexor tendon)

Palmaris Longus Insertion

Flexor retinaculum & Palmar aponeurosis

Palmaris Longus Action

Assists flexion of wrist

Palmaris Longus Innervation

Median n (C7, 8)

Flexor Carpi Ulnaris Origin

Humeral head: Medical epicondyle of humerus (common flexor tendon) Ulnar head: Proximal posterior ulna, Olecranon process of ulna

Flexor Carpi Ulnaris Insertion

Pisiform carpal bone, Hamate carpal bone, and base of 5th metacarpal

Flexor Carpi Ulnaris Action

Flexion, Adduction of wrist (ulnar deviation)

Flexor Carpi Ulnaris Innervation

Ulnar n (C7, 8)

Flexor Digitorum Superficialis Origin

Humeroulnar head: Medial epicondyle of humerus (Common flexor tendon), Coronoid process of ulna Radial head: Anterior oblique line of radius

Flexor Digitorum Superficialis Insertion

Sides of shafts of middle phalanges of 4 fingers

Flexor Digitorum Superficialis Action

Flexion of 4 fingers at PIP joints, Assists flexion of wrist

Flexor Digitorum Superficialis Innervation

Median n (C7, 8, T1)

Flexor Digitorum Profundus Origin

Proximal 3/4 of anterior ulna, Interosseous membrane

Flexor Digitorum Profundus Insertion

Bases of distal phalanges of 4 fingers

Flexor Digitorum Profundus Action

Flexion of 4 fingers at DIP joints, Assists flexion of wrist

Flexor Digitorum Profundus Innervation

Radial 2 fingers: Median n (C8, T1) Ulnar 2 fingers: Ulnar n (C8, T1)