W9 Bones of the Chest & Upper Limb; Muscles of the Back, Chest, and Shoulder Upper Limb Regions

Flashcards for Anatomy Lecture on Bones and Muscles of the Chest and Upper Limb

Brachium

Shoulder to elbow

Antebrachium

Elbow to wrist

Upper Limb Regions

Connection to Trunk: By pectoral girdle (scapula & clavicle)

Scapula

Flat bone, posterior-lateral thorax, over ribs 2–7

Acromion process

Lateral projection, forms shoulder apex, articulates with clavicle

Glenoid cavity

Shallow socket, articulates with humeral head

Clavicle

S-shaped, long bone, first to ossify in embryo

Medial end (of clavicle)

Rounded, articulates with sternum

Lateral end (of clavicle)

Flattened, forms acromioclavicular joint

Sternum

Bony plate anterior to heart

Key landmarks of sternum

Jugular notch, sternal angle, articular facets for ribs 1–7

Proximal end of Humerus

Head articulates with glenoid cavity

Distal end of Humerus

Capitulum (articulates with radius), trochlea (with ulna)

Ulna (medial)

Olecranon (elbow point), trochlear notch (articulates with humerus), coronoid process

Radius (lateral)

Head (articulates with humerus & ulna), neck, radial tuberosity (biceps attachment)

Wrist

8 carpal bones (4 proximal, 4 distal); flexibility allows bending/twisting

Carpal tunnel syndrome

Inflammation/compression of median nerve

Phalanges

Thumb has 2, other fingers have 3 each (proximal, middle, distal)

Origin

Stationary attachment

Insertion

Movable attachment

Prime mover

Main force for movement

Synergist

Aids prime mover

Antagonist

Opposes prime mover; relaxes for movement control

Fixator

Prevents bone movement

Erector spinae (superficial)

Spinalis, longissimus, iliocostalis groups

Erector spinae (deep)

Semispinalis, multifidus, interspinales, intertransversarii, rotatores

Pectoralis major: Origin, Action

Sternum, ribs, clavicle; Arm flexion, adduction, medial rotation; used in climbing

Pectoralis minor: Origin, Action

Ribs 3–5; Depresses shoulder, accessory in respiration

Serratus anterior: Origin, Action

Upper 8 ribs; Scapula protraction, rotation; 'winged' scapula if weak

Trapezius: Origin, Action

Nuchal lines, cervical/thoracic spines; Neck extension, scapula elevation/rotation, shoulder bracing

Latissimus dorsi: Origin, Action

T6–12 spines, lower ribs, iliac crest, thoracolumbar fascia, scapula; Arm adduction, extension, medial rotation; raises body in climbing

Levator scapulae: Origin, Action

C1–C4 transverse processes; Scapula elevation, tilts glenoid down

Rhomboid minor: Origin, Action

C7–T1/2 spines; Elevation, retraction of scapula

Rhomboid major: Origin, Action

T2–T5 spines; Retraction, elevation of scapula

Deltoid (Shoulder Region): Origin, Action

Clavicle (Anterior), Acromion (Middle), Spine of scapula (Posterior); All fibers: Abduction

Supraspinatus: Origin, Action

Supraspinous fossa; Humerus abduction

Infraspinatus: Origin, Action

Infraspinous fossa; Lateral rotation

Teres minor: Origin, Action

Lateral scapula border; Lateral rotation

Subscapularis: Origin, Action

Costal scapula surface; Medial rotation

Teres major: Origin, Action

Inferior angle/lateral border of scapula; Medial rotation