Lecture Notes on Human Musculature

A collection of vocabulary flashcards covering muscle origins, insertions, innervations, and actions for the upper body and extremities based on lecture notes.

Serratus Anterior

Originates from the external surface of ribs $1$-$8$ or $9$ and inserts on the anterior surface of the medial border of the scapula; innervated by the $C5$-$C7$ Long Thoracic Nerve.

Upper Trapezius

Originates from the Occiput, Ligamentum nuchae, and $C7$; inserts on the lateral $1/3$ of the clavicle, acromion, and spine of the scapula; actions include head/neck extension, lateral flexion, and scapular elevation.

Middle Trapezius

Originates from $T1$-$T5$ spinous processes; its primary action is scapular adduction and stabilization.

Lower Trapezius

Originates from $T6$-$T12$ spinous processes; performs scapular adduction, depression, and upward rotation.

Levator Scapulae

Originates from $C1$-$C4$ transverse processes and inserts on the medial border of the scapula between the superior angle and the spine; innervated by $C3$-$C4$ and $C5$ dorsal scapular nerve.

Rhomboid Major

Originates from $T2$-$T5$ spinous processes and facilitates scapular adduction, downward rotation, and elevation.

Latissimus Dorsi

Inserts on the intertubercular groove of the humerus and is innervated by the $C6$-$C8$ thoracodorsal nerve.

Pectoralis Major

Muscle fibers that perform shoulder adduction, internal rotation, and elevation of the thorax; upper fibers handle flexion and horizontal adduction.

Pectoralis Minor

Originates from ribs $3$-$5$ and inserts on the medial surface of the coracoid process; performs scapular abduction, depression, and downward rotation.

Anterior Deltoid

Part of the deltoid responsible for shoulder abduction, flexion, internal rotation, and horizontal adduction.

Posterior Deltoid

Originates from the spine of the scapula and performs shoulder abduction, extension, external rotation, and horizontal abduction.

Supraspinatus

Originates from the supraspinous fossa and performs shoulder abduction while stabilizing the GH joint.

Infraspinatus

Responsible for shoulder external rotation and adduction; innervated by the $C5$-$C6$ suprascapular nerve.

Subscapularis

Originates from the subscapular fossa and inserts on the lesser tubercle of the humerus; performs shoulder internal rotation.

Biceps Brachii

Consists of a short head from the coracoid process and a long head from the supraglenoid tubercle; performs elbow flexion, forearm supination, and shoulder flexion.

Brachialis

An elbow flexor that originates on the distal half of the anterior humerus and inserts on the ulnar tuberosity and coronoid process.

Triceps Brachii

Consists of three heads (long, lateral, and medial) that insert on the olecranon process to perform elbow extension.

Brachioradialis

Innervated by the $C5$-$C6$ radial nerve; performs elbow flexion in a neutral position.

Pronator Teres

Originates from the medial epicondyle and coronoid process; performs forearm pronation and assists in elbow flexion.

Extensor Carpi Radialis Longus

Performs wrist extension and radial deviation; innervated by the $C6$-$C7$ radial nerve.

Flexor Carpi Ulnaris

Performs wrist flexion and ulnar deviation; innervated by the $C7$-$T1$ ulnar nerve.

Flexor Digitorum Profundus

Responsible for flexion of the $2nd$-$5th$ fingers at the DIP, MP, and PIP joints; innervated by the median nerve ($2nd$ and $3rd$ digits) and ulnar nerve ($4th$ and $5th$ digits).

Dorsal Interossei

Innervated by the ulnar nerve ($C8$-$T1$); responsible for abduction and flexion of the $2nd$, $3rd$, and $4th$ digits at the MP joints.

Palmar (Volar) Interossei

Performs adduction and MP flexion for the $1st$, $2nd$, $4th$, and $5th$ digits.

Opponens Pollicis

Originates from the trapezium tubercle and flexor retinaculum; performs thumb opposition.

Adductor Pollicis

Originates from the capitate and $2nd$ and $3rd$ metacarpals; performs thumb CMC and MP adduction.