1
With the elbow flexed to 90 degrees, a person turns the palm upward against resistance. Which muscle is being tested, and what action is occurring?
The biceps brachii; supination
This muscle performs protraction while also preventing the scapula from lifting away from the thoracic wall.
Serratus anterior
A person can flex the proximal interphalangeal joints but has difficulty flexing the distal phalanges at the distal interphalangeal joints of the medial four digits. Which muscle is affected?
Flexor Digitorum Profundus
This triangular depression near the thumb is bordered by three muscles and contains the radial artery and superficial radial nerve.
What is the anatomical snuff box?
The head of this bone articulates with the scapula at a ball-and-socket joint. Name the bone, the name of the cavity, and the joint.
A person can continue abducting the arm after it has been lifted 15 degrees but cannot begin the movement alone. Which muscle is most likely injured?
The supraspinatus
One muscle stabilizes and depresses the clavicle, while another stabilizes the scapula. Name both muscles in that order.
Which muscle flexes the proximal interphalangeal and metacarpophalangeal joints but does not act on the thumb?
Flexor Digitorum Superficialis
Name the three muscles that delineate the anatomical snuff box.
One anterior arm muscle flexes and adducts the arm at the shoulder, while another flexes the forearm at the elbow during curls. Name both.
Coracobrachialis, brachialis
A person spreads the fingers away from the middle finger and then moves them toward the back of the hand. Name both actions.
Abduction and extension
A person cannot elevate the arm past 90 degrees, and the medial border and inferior angle of the scapula are visible on the back. Name the condition and the affected muscle.
Winged Scapula; Serratus Anterior
Flexor retinaculum (transverse carpal ligament) holds down 3 tendons and a nerve. What is this space that they pass through called?
The carpal tunnel
Which two muscles forming the snuff box extend different parts of the thumb, with one acting on the proximal phalanx and the other acting on the distal phalanx, respectively?
Name the three heads of the posterior-compartment muscle that extends the forearm at the elbow.
Tricep brachii has the medial, lateral, and long head.
Name the superficial (extrinsic) forearm muscle that pronates and flexes the forearm and the deepest (intrinsic) flexor-forearm muscle that also performs pronation.
Pronator teres (superficial/extrinsic) and pronator quadratus (deep/intrinsic).
Two muscles internally rotate and adduct the arm. One is part of SITS and is the strongest internal rotator; the other is not part of SITS. Name both.
Subscapularis; Teres major
A person cannot flex the phalanges of the thumb and also cannot pronate using the deepest muscle in the flexor forearm. Name both affected muscles.
Flexor pollicis longus; Pronator quadratus
A person has pinpoint pain in the floor of the anatomical snuff box after a wrist injury. Name the likely injury and the result if it is untreated.
Scaphoid fracture leads to avascular necrosis if left untreated
A person hears a pop, has pain when lifting the arm overhead, and develops a visible bulge after one head of a muscle disconnects from its origin. Name the injury and deformity.
Rupture of long head of biceps makes your biceps look similar to the biceps of the fictional character "Popeye"
A person flexes and internally rotates the arm at the shoulder, flexes the forearm at the elbow, and then turns the palm upward against resistance. Name the deltoid fibers and arm muscle responsible for these actions.
Anterior deltoid fibers and biceps brachii
Name the four muscles that stabilize the shoulder as SITS, then identify which two externally rotate, which one begins abduction, and which is the strongest internal rotator.
SITS-
Supraspinatus (Abducts), Infraspinatus (External Rotation), Teres Minor (External Rotation), Subscapularis (Internal Rotation)
Name the superficial forearm muscle involved in pronating the forearm, intermediate forearm muscle involved in flexing the proximal interphalangeal joints, and deep flexor forearm muscle involved in flexing the distal interphalangeal joints, respectively.
Pronator teres; Flexor digitorum superficialis; Flexor digitorum profundus
What is the name of the nerve that passes through the carpal tunnel?
One person cannot begin arm abduction, another cannot elevate the arm past 90 degrees and has a visible medial scapular border, and a third has numbness in digits 1–3 and half of the fourth digit. Name the three conditions or injuries in order.