Muscles That Move the Pectoral Girdle, Arm, and Forearm

Vocabulary flashcards covering the major muscles, connective structures, and groups discussed in the lecture on pectoral girdle, arm, and forearm movement.

Levator scapulae

Muscle running from the cervical vertebrae to the superior angle of the scapula; elevates the scapula when it contracts.

Rhomboid major

Larger, inferior rhomboid muscle connecting vertebral spinous processes to the medial border of the scapula; retracts (adducts) and downward-rotates the scapula.

Rhomboid minor

Smaller, superior rhomboid muscle; assists rhomboid major in retracting and downward-rotating the scapula.

Serratus anterior

Saw-toothed muscle originating on anterior ribs and inserting on the scapula’s medial border (especially the inferior angle); protracts scapula and is nicknamed the “hugging muscle.”

Pectoralis minor

Thin chest muscle from ribs 3-5 to the coracoid process; pulls the scapula forward and downward.

Trapezius

Large kite-shaped back muscle attaching to skull, vertebrae, and spine of scapula; upper, middle, and lower fibers elevate, retract, or depress the scapula.

Deltoid

Triangular shoulder muscle from clavicle and scapular spine to the deltoid tuberosity of the humerus; main abductor of the arm.

Latissimus dorsi

Broad back muscle arising from thoracolumbar fascia and inserting on anterior humerus; extends, adducts, and medially rotates the arm (e.g., power stroke in swimming).

Thoracolumbar fascia (aponeurosis)

Sheet-like connective tissue in lower back that serves as broad origin for latissimus dorsi and other muscles.

Teres major

Muscle from inferior angle of scapula to anterior humerus; medially rotates and adducts the arm, acting opposite teres minor.

Teres minor

Small posterior scapular muscle inserting on posterior humerus; laterally rotates the arm and is part of the rotator cuff.

Infraspinatus

Rotator-cuff muscle filling the infraspinous fossa; laterally rotates the humerus.

Supraspinatus

Rotator-cuff muscle in the supraspinous fossa; initiates first 15° of arm abduction.

Subscapularis

Rotator-cuff muscle occupying the subscapular fossa (anterior scapula); medially rotates the humerus.

Rotator cuff

Collective term for supraspinatus, infraspinatus, teres minor, and subscapularis, which stabilize the glenohumeral joint by encircling the humeral head.

Coracobrachialis

Slender muscle from coracoid process to medial humerus; flexes and adducts the arm.

Biceps brachii

Two-headed anterior arm muscle (long head originates at supraglenoid tubercle, short head at coracoid); flexes elbow and supinates forearm.

Brachialis

Flat muscle deep to biceps brachii; main flexor of the elbow, inserting on the ulna.

Triceps brachii

Three-headed posterior arm muscle (long, lateral, medial heads) inserting on olecranon; primary extensor of the elbow.

Anconeus

Small triangular muscle from lateral epicondyle of humerus to ulna; assists triceps in elbow extension.

Brachioradialis

Forearm muscle from distal humerus to radial styloid; flexes the elbow especially in mid-pronated position (handshake muscle).

Pronator teres

Superficial forearm muscle running from medial epicondyle and ulna to mid-radius; pronates the forearm.

Supinator

Deep forearm muscle from lateral epicondyle and ulna to proximal radius on posterior side; supinates the forearm.

Pronator quadratus

Deep square muscle spanning distal ulna to distal radius; primary pronator of the forearm at the wrist level.

Spinalis thoracis

Medial column of the erector spinae in thoracic region; extends vertebral column.

Longissimus thoracis

Intermediate erector-spinae column; extends and laterally flexes spine.

Iliocostalis thoracis

Lateral erector-spinae column attaching to ribs; aids in spinal extension and posture.

Serratus posterior (superior & inferior)

Thin respiratory muscles on the back; not responsible for pectoral girdle movement (mentioned for contrast).

Rotatores

Small deep back muscles that rotate adjacent vertebrae; noted but not emphasized in arm movement lecture.