Upper Limb Anatomy: Bones, Muscles, Nerves, and Blood Vessels

Comprehensive vocabulary flashcards covering the osteology, muscular attachments, innervation, and vascular supply of the human upper limb.

Sternoclavicular Joint

The only skeletal point of articulation that attaches the pectoral girdle and upper limb to the trunk.

Scapula

A large, flat, triangular bone overlapping the second to seventh ribs on the posterolateral thoracic wall, possessing costal and dorsal surfaces, three borders, three angles, and three processes.

Glenoid Cavity

A shallow articular socket on the truncated lateral angle (head) of the scapula that articulates with the head of the humerus to form the glenohumeral joint.

Spinoglenoid (Great Scapular) Notch

A notch situated between the lateral border of the spine of the scapula and the dorsal aspect of the neck, through which the supraspinous and infraspinous fossae are confluent.

Infraglenoid Tubercle

A rough, triangular widening at the upper end of the lateral border of the scapula that gives attachment to the long head of the triceps brachii.

Supraglenoid Tubercle

A small, rough projection immediately above the glenoid cavity on the root of the coracoid process providing origin for the long head of the biceps brachii.

Suprascapular Notch

A notch on the lateral end of the superior border of the scapula, bridged by the superior transverse ligament to form a foramen transmitting the suprascapular nerve.

Superior Transverse Ligament

A ligament bridging the suprascapular notch beneath which the suprascapular nerve passes into the supraspinous fossa, while the suprascapular vessels pass above it.

Coracoid Process

A process arising from the summit of the scapular head that hooks forwards and laterally; it gives attachment to the pectoralis minor, coracobrachialis, and short head of biceps brachii.

Acromial Angle

The prominent, palpable subcutaneous junction where the inferior border of the crest of the scapular spine becomes continuous with the lateral border of the acromion.

Clavicle

A wholly subcutaneous, S-shaped bone extending from the sternal manubrium to the acromion; its medial two-thirds is convex forwards and its lateral third is concave forwards.

Conoid Tubercle

A prominence on the inferior aspect of the clavicle near its posterior border at the junction of the lateral fourth with the rest of the shaft, attaching the conoid ligament.

Trapezoid Line

A rough ridge running anterolaterally from the conoid tubercle towards the acromial end of the clavicle, providing attachment for the trapezoid ligament.

Anatomical Neck of the Humerus

A slight constriction immediately adjoining the articular margin of the humeral head, indicating the line of shoulder joint capsular attachment except at the intertubercular sulcus.

Surgical Neck of the Humerus

The ill-defined constriction of the humerus distal to the tubercles, closely related medially to the axillary nerve and the posterior circumflex humeral artery.

Greater Tubercle of the Humerus

The most lateral proximal feature of the humerus, possessing three posterosuperior facets for attachment of the supraspinatus (uppermost), infraspinatus (middle), and teres minor (lowest).

Lesser Tubercle of the Humerus

An anterior prominence just distal to the anatomical neck of the humerus that provides insertion for the subscapularis muscle and the transverse ligament of the shoulder joint.

Intertubercular Sulcus (Bicipital Groove)

A groove on the proximal humerus conveying the tendon of the long head of the biceps brachii, its synovial sheath, and an ascending branch of the anterior circumflex humeral artery.

Radial (Spiral) Groove

A broad, shallow depression descending obliquely laterally and forwards across the posterior and lateral surfaces of the humeral shaft, transmitting the radial nerve and profunda brachii vessels.

Capitulum of the Humerus

A smooth, rounded lateral condylar projection covering anterior and inferior surfaces (less than half a sphere) that articulates with the cup-shaped head of the radius.

Trochlea of the Humerus

A pulley-shaped medial articular surface of the distal humerus extending across anterior, inferior, and posterior aspects, articulating with the trochlear notch of the ulna.

Olecranon Fossa

A deep posterior depression on the distal humerus proximal to the trochlea that lodges the apex of the ulnar olecranon during full elbow extension.

Coronoid Fossa

A small depression on the anterior surface of the distal humerus proximal to the trochlea that receives the anterior margin of the ulnar coronoid process in full elbow flexion.

Radial Fossa

A shallow depression on the anterior distal humerus proximal to the capitulum that receives the margin of the radial head in full flexion.

Radial Dorsal Tubercle

A palpable dorsal projection on the distal radius in line with the index-middle finger cleft; it is grooved medially by the extensor pollicis longus tendon.

Trochlear Notch of the Ulna

A large C-shaped articular depression formed by the olecranon and coronoid processes that articulates with the humeral trochlea.

Radial Notch of the Ulna

A shallow, smooth, oval depression on the lateral aspect of the coronoid process that articulates with the circumference of the head of the radius.

Oblique Cord

An inconstant fascial band extending from the lateral side of the ulnar tuberosity to the radius distal to its tuberosity, with fibres running perpendicular to the interosseous membrane.

Interosseous Membrane of the Forearm

A fibrous collagenous sheet whose fibres run distomedially from the radius to the ulna, connecting the two bones and providing attachments for deep forearm muscles.

Carpus

The skeleton of the wrist comprising eight bones in two rows: proximal (scaphoid, lunate, triquetral, pisiform) and distal (trapezium, trapezoid, capitate, hamate).

Hamulus (Hook of Hamate)

An unciform curved projection arising from the palmar surface of the hamate bone that forms part of the medial boundary of the carpal tunnel.

Carpal Tunnel

An osseofibrous canal bounded by the concave palmar surface of the carpal bones and bridged by the flexor retinaculum, transmitting flexor tendons and the median nerve.

Trapezius Muscle

A large superficial back muscle supplied motor-wise by the spinal accessory nerve that controls, elevates, retracts, and rotates the scapula.

Latissimus Dorsi Muscle

A broad back muscle inserting into the floor of the intertubercular sulcus of the humerus, supplied by the thoracodorsal nerve, that extends, adducts, and medially rotates the humerus.

Levator Scapulae Muscle

A muscle arising from transverse processes of C1 to C4 vertebrae and inserting along the medial scapular border from the superior angle to the spine, elevating the scapula.

Pectoralis Major Muscle

A large chest muscle with clavicular and sternocostal heads inserting into the lateral lip of the intertubercular sulcus, acting to adduct and medially rotate the humerus.

Pectoralis Minor Muscle

A thin anterior chest muscle originating from the third to fifth ribs and inserting into the coracoid process, assisting in drawing the scapula forwards and downwards.

Serratus Anterior Muscle

A fan-shaped muscle arising from the upper ribs (1 to 10) and inserting onto the anterior medial scapular border; innervated by the long thoracic nerve, it protracts and rotates the scapula.

Rotator Cuff

A musculotendinous cuff formed by the tendons of subscapularis, supraspinatus, infraspinatus, and teres minor that stabilizes the humeral head against the glenoid cavity.

Subscapularis Muscle

A muscle occupying the costal surface of the scapula that inserts into the lesser tubercle of the humerus, functioning as a medial rotator of the humerus.

Supraspinatus Muscle

A muscle occupying the supraspinous fossa that inserts into the highest facet on the greater tubercle of the humerus, aiding the deltoid in initiating arm abduction.

Infraspinatus Muscle

A muscle arising from the infraspinous fossa that inserts onto the middle facet of the greater tubercle of the humerus, acting primarily as a lateral rotator of the humerus.

Teres Minor Muscle

A muscle arising from the lateral dorsal strip of the scapula that inserts into the lowest facet of the greater tubercle, acting with infraspinatus to laterally rotate the humerus.

Teres Major Muscle

A thick muscle originating from the dorsal aspect of the scapular inferior angle that inserts into the medial lip of the intertubercular sulcus, adducting and medially rotating the humerus.

Coracobrachialis Muscle

An anterior arm muscle arising from the coracoid process apex and inserting midway along the medial humeral shaft, innervated by the musculocutaneous nerve.

Biceps Brachii Muscle

A two-headed anterior arm muscle inserting onto the posterior radial tuberosity and bicipital aponeurosis, functioning as a powerful supinator and flexor of the elbow.

Brachialis Muscle

A primary elbow flexor arising from the lower half of the anterior humerus and inserting into the ulnar tuberosity and coronoid process.

Triceps Brachii Muscle

A three-headed muscle on the posterior arm inserting onto the proximal olecranon of the ulna, acting as the primary extensor of the elbow joint.

Pronator Teres Muscle

A superficial forearm muscle with humeral and ulnar heads that inserts onto the midpoint of the lateral radial shaft to pronate the forearm.

Palmaris Longus Muscle

A slender superficial forearm flexor whose tendon passes superficial to the flexor retinaculum to expand into the palmar aponeurosis, anchoring palmar skin against shearing forces.

Flexor Digitorum Superficialis Muscle

An intermediate anterior forearm muscle with humero-ulnar and radial heads whose four tendons split to insert onto the middle phalanges of the medial four digits.

Flexor Digitorum Profundus Muscle

A deep flexor of the forearm originating mainly from the ulna and interosseous membrane, whose four tendons pass through the FDS tendons to insert on distal phalangeal bases.

Flexor Pollicis Longus Muscle

A deep muscle arising from the anterior surface of the radius and interosseous membrane that inserts into the palmar base of the distal phalanx of the thumb.

Pronator Quadratus Muscle

A deep, quadrangular muscle extending transversely between the distal quarters of the anterior shafts of the ulna and radius, functioning as the principal pronator of the forearm.

Brachioradialis Muscle

A superficial muscle arising from the upper two-thirds of the lateral supracondylar ridge of the humerus and inserting above the radial styloid process, flexing the elbow in mid-pronation.

Supinator Muscle

A deep posterior forearm muscle wrapping around the proximal third of the radius that rotates the radius laterally to supinate the forearm.

Flexor Retinaculum (Transverse Carpal Ligament)

A dense fibrous band attached medially to the pisiform and hook of hamate and laterally to the scaphoid and trapezium, forming the roof of the carpal tunnel.

Extensor Retinaculum

A fibrous band passing obliquely across the dorsal wrist forming six distinct fibro-osseous compartments for the carpal and digital extensor tendons.

Quadrangular Space

An anatomical space bounded by subscapularis/teres minor, teres major, the long head of triceps, and the humeral surgical neck, conducting the axillary nerve and posterior circumflex humeral vessels.

Axillary Nerve

A nerve arising from the posterior cord (C5, C6) that passes through the quadrangular space to supply the deltoid and teres minor, ending as the upper lateral cutaneous nerve of the arm.

Musculocutaneous Nerve

A branch of the lateral cord (C5–C7) that pierces coracobrachialis, innervates the anterior arm muscles (coracobrachialis, biceps, brachialis), and terminates as the lateral cutaneous nerve of the forearm.

Median Nerve

A nerve formed by roots from the lateral and medial cords (C5–T1) that runs through the anterior arm, cubital fossa, and carpal tunnel to supply flexor muscles and thenar skin.

Anterior Interosseous Nerve

A motor branch of the median nerve descending on the anterior surface of the interosseous membrane to supply flexor pollicis longus, the lateral half of flexor digitorum profundus, and pronator quadratus.

Ulnar Nerve

A terminal branch of the medial cord (C8, T1) passing behind the medial epicondyle into the medial forearm and hand, supplying intrinsic hand muscles and ulnar-sided skin.

Radial Nerve

The largest branch of the brachial plexus (C5–T1), arising from the posterior cord and traversing the radial groove to supply the extensor compartments of the arm and forearm.

Posterior Interosseous Nerve

The deep motor continuation of the radial nerve that pierces the supinator muscle to innervate the extensor muscles on the dorsum of the forearm.

Axillary Artery

The continuation of the subclavian artery extending from the outer border of the first rib to the inferior border of teres major/pectoralis major, divided into three parts by pectoralis minor.

Thoraco-Acromial Artery

A branch of the second part of the axillary artery that pierces the clavipectoral fascia and divides into pectoral, acromial, clavicular, and deltoid branches.

Subscapular Artery

The largest branch of the axillary artery, arising from its third part and dividing into the circumflex scapular and thoracodorsal arteries.

Arteria Profunda Brachii

A major branch of the proximal brachial artery that accompanies the radial nerve into the radial groove, dividing into deltoid, nutrient, middle collateral, and radial collateral arteries.

Radial Artery

A terminal branch of the brachial artery that runs along the lateral forearm, traverses the anatomical snuffbox over the scaphoid and trapezium, and completes the deep palmar arch.

Ulnar Artery

A terminal branch of the brachial artery descending down the medial forearm, crossing superficial to the flexor retinaculum, and forming the principal contribution to the superficial palmar arch.

Common Interosseous Artery

A short branch from the ulnar artery arising distal to the radial tuberosity that bifurcates into the anterior and posterior interosseous arteries.

Superficial Palmar Arch

An arterial arch in the palm lying superficial to long flexor tendons, formed mainly by the ulnar artery and completed by the superficial palmar branch of the radial artery.

Deep Palmar Arch

An arterial arch formed by the terminal part of the radial artery and the deep palmar branch of the ulnar artery, lying across the bases of the metacarpals deep to long flexor tendons.

Cephalic Vein

A superficial vein beginning at the radial side of the dorsal venous network, ascending the anterolateral limb, passing in the deltopectoral groove, and draining into the axillary vein.

Basilic Vein

A superficial vein originating on the ulnar side of the dorsal venous network that ascends medially, pierces deep fascia midway along the arm, and becomes the axillary vein at the lower border of teres major.

Median Cubital Vein

A superficial vein situated in front of the elbow that shunts blood obliquely from the cephalic vein to the basilic vein across the bicipital aponeurosis.

Axillary Vein

The venous continuation of the basilic vein at the lower border of teres major that ascends medial to the axillary artery to become the subclavian vein at the outer border of the first rib.