Upper Extremity Musculoskeletal Anatomy and Neurological Testing

Comprehensive vocabulary flashcards covering muscle insertions, actions, innervations, joint/ligament restrictions, and neurological diagnostic tests for the upper extremity.

Pectoralis Major

Muscle originating from the medial half of clavicle, sternum, and costal cartilages $1-7$; inserts at the intertubercular groove; performs IR, FLEX, and ADD of humerus; innervated by medial and lateral pectoral nn.

Serratus Anterior

Muscle originating from the anterior surface of the medial border of the scapula and ribs $1-9$ lateral parts; rotates glenoid cavity superiorly and protracts scapula; innervated by the Long thoracic n.

Deltoid

Muscle originating from the scapular spine, acromion, and lateral clavicle; inserts at the deltoid tuberosity; performs ABD, FLEX, EXT, IR and ER of humerus; innervated by the Axillary n.

Latissimus Dorsi

Muscle originating from the thoracolumbar fascia and iliac crest; inserts at the floor of the intertubercular groove; performs EXT, ADD, and IR of humerus; innervated by the Thoracodorsal n.

Teres Minor

Rotator cuff muscle originating from the lateral border of scapula and inserting at the greater tubercle of humerus; performs ER of humerus; innervated by the Axillary n.

Subscapularis

Rotator cuff muscle originating from the subscapular fossa and inserting at the lesser tubercle of humerus; performs IR of humerus; innervated by upper and lower subscapular nn.

Supraspinatus

Rotator cuff muscle originating from the supraspinous fossa and inserting at the greater tubercle; centers the humeral head into the glenoid fossa; innervated by the Suprascapular n.

Infraspinatus

Rotator cuff muscle originating from the infraspinous fossa and inserting at the greater tubercle; performs ER of humerus; innervated by the Suprascapular n.

Pectoralis Minor

Muscle originating from ribs $3-5$ and inserting at the coracoid process of scapula; performs anteriorly tilt and depression of scapula; innervated by the medial pectoral n.

Trapezius

Muscle originating from the external occipital protuberance and spinous process $C7-T12$; inserts at the lateral one-third of the clavicle, acromion, and spine of scapula; performs retraction, depression, and elevation; motor innervation via spinal accessory n. (CN XI) and proprioception via $C3-C4$.

Rhomboid Major

Muscle originating from spinous process $T2-T5$ and inserting inferior to scapular spine on the medial border; performs retraction, downward rotation, and depression; innervated by the Dorsal scapular n.

Levator Scapulae

Muscle originating from transverse process $C1-C4$ and inserting at the superior angle of scapula; performs scapular elevation and rotation to tilt the glenoid cavity inferiorly; innervated by the Dorsal scapular n.

Brachioradialis

Muscle originating from the lateral supracondylar ridge and inserting at the radial styloid process; performs FLEX of forearm in neutral position; innervated by the Radial n.

Biceps Brachii-Long Head

Muscle originating from the supraglenoid tubercle of scapula; performs shoulder FLEX, supination, and FLEX of forearm; innervated by the Musculocutaneous n.

Triceps Brachii-Long Head

Muscle originating from the infraglenoid tubercle of scapula and inserting at the olecranon process of Ulna; performs shoulder ADD and EXT, and elbow EXT; innervated by the Radial n.

Flexor Digitorum Superficialis

Muscle originating from the medial epicondyle of humerus and oblique line of radius; inserts at the middle phalanges of digits $2-5$; performs FLEX of PIP of digits $2-5$; innervated by the Median n.

Flexor Digitorum Profundus

Muscle originating from the anterior and medial surface of ulna and interosseous membrane; inserts at the distal phalanges of digits $2-5$; performs FLEX of DIP of digits $2-5$; innervated by both Median n. and Ulnar n.

Pronator Teres

Muscle originating from the medial epicondyle of humerus and coronoid process; inserts at the radial shaft; performs pronation and FLEX of forearm; innervated by the Median n.

Abductor Pollicis Longus

Muscle originating from the posterior surfaces of the radius, ulna, and interosseous membrane; inserts at the base of the $1st$ metacarpal; abducts and extends CMC of the thumb; innervated by the Radial n.

Glenohumeral Joint

The main shoulder joint located between the humeral head and the glenoid fossa of the scapula.

Scapulothoracic articulation

Not a true joint; refers to where the scapula sits on top of the ribs; has a relationship to ensure movement.

Coracoacromial Ligament

Strong triangular ligament from the coracoid process to the acromion process of the scapula; restricts superior displacement of the humeral head.

Transverse Humeral Ligament

Ligament connecting the greater and lesser tubercles; holds down the long head of the Biceps Brachii.

Glenoid Labrum

Fibrocartilage rim of the glenoid fossa providing shock absorption, nutrition, and increased surface area to increase stability of the GH joint.

Annular Ligament

Connects the ulna and radial head; restricts displacement inferiorly of the radial head away from the ulna (traction force).

Interosseus Membrane

Thin, broad, collagenous sheet holding the radius and ulna together; stabilizes arm during pronation/supination and serves as an attachment point.

Flexor Retinaculum / Transverse Carpal

Connects medially to the pisiform and hamate and laterally to the scaphoid and trapezium; holds $9$ flexor tendons and the Median n. in place, creating the Carpal Tunnel.

Triangular Fibrocartilage Complex

Fibrous cartilaginous structure at the distal ulna that stabilizes movements of the radiocarpal joint around the ulna.

Babinski Test

Neurological reflex test where a reflex hammer is run up the plantar aspect of the foot; positive if the great toe extends and others splay, indicating an upper motor neuron lesion.

Hoffman Sign

Upper extremity equivalent of Babinski's Test; clinician flicks middle finger nail toward flexion; positive if there is flexion/twitching of the distal phalanx of the ipsilateral thumb.

Deep Tendon Reflex Grade 4+

Interpretation representing hyperactive or non-sustained clonus; categorized as Abnormal.

Pretty Fat Pissed Flamingo

Mnemonic for the superficial anterior forearm muscles: Pronator Teres, Flexor Carpi Radialis, Palmaris Longus, and Flexor Carpi Ulnaris.

Superfish

Mnemonic for the intermediate anterior forearm muscle: Flexor Digitorum Superficialis.

Profound Polly Q

Mnemonic for the deep anterior forearm muscles: Flexor Digitorum Profundus, Flexor Pollicis Longus, and Pronator Quadratus.