Unit 2 Anatomy Small Group Quiz

A 32-year-old woman delivered a large baby after a difficult labor. At delivery, the infant's head emerged, but the shoulders were "stuck" behind the maternal symphysis pubis. Effort and maneuvers to free them up stretched the brachial plexus. The infant was noted to have a good cry and color but was not moving his right arm. Which injured nerve is partially responsible for the baby inability to abduct, flex and laterally rotate his right arm?

*Erb's Palsy* usually results from a violent increase in the angle between the neck and shoulder (e.g., when thrown from a motorcycle or during a difficult delivery) traction, compression, or stretching either from fall or shoulder dystocia upper brachial plexus lesion of C5-6 arm adducted, extended and medially rotated, the forearm extended and pronated, and the palm facing backward; the fingers may be flexed (waiter's tip position), sensory loss over lateral aspect of upper arm

Clavicle fractures occur most frequently at the junction of the middle and lateral thirds of the clavicle. The following vessels and nerves are the most likely at risk because they lie behind only the thin subclavius muscle: A- Subclavian artery and trunks of brachial plexus B- Subclavian vein and cords of brachial plexus C- Axillary artery and trunks of brachial plexus D- Axillary vein and roots of brachial plexus E- Subclavian artery and roots of brachial plexus

A- Subclavian artery and trunks of brachial plexus

Which of the following is correct pertaining to the interossei and lumbrical muscles of the hand? A- The palmar interossei, dorsal interossei, and lumbricals together can produce flexion at the metacarpophalangeal joints and extension at the interphalangeal joints. B- The palmar interossei, dorsal interossei, and lumbricals together can produce extension at the metacarpophalangeal joints and flexion at the interphalangeal joints. C- The palmar and dorsal interossei produce abduction of the fingers, whereas the lumbricals can produce adduction. D- The palmar interossei and lumbricals can produce adduction of the fingers, whereas the dorsal interossei can produce abduction. E- The dorsal interossei and lumbricals can produce abduction of the fingers, whereas the palmar interossei can produce adduction.

A- The palmar interossei, dorsal interossei, and lumbricals together can produce flexion at the metacarpophalangeal joints and extension at the interphalangeal joints.

Elbow tendonitis (tennis elbow) is associated with: A- inflammation of the periosteum of the lateral epicondyle of the humerus. B- inflammation of the medial collateral ligament. C- inflammation of the annular ligament. D- rupture of the tendon of the extensor digitorum. E- transient subluxation of the humero-radial- ulnar joint.

A- inflammation of the periosteum of the lateral epicondyle of the humerus. > extensor muscles of forearm

Which injured nerve is partially responsible for the baby inability to abduct, flex and laterally rotate his right arm?

Axillary Nerve

Which muscle when avulsed from the supraglenoid tubercle forms a ball near the distal end of the arm called Popeye deformity A- Brachialis B- Biceps Brachii C- Triceps brachii D- Coracobrachialis E- Brachioradialis

B- Biceps Brachii

The axillary vein is usually formed by the joining of which two veins? A- brachial & cephalic veins B- brachial & basilic veins C- cephalic & basilic veins D- subclavian & basilic veins E- median cubital & cephalic veins

B- brachial & basilic veins

In the emergency room you see a 65-year-old woman who fell on her outstretched right hand while walking on ice. Upon examination of the right limb, you feel and see a dorsal protrusion just proximal to the wrist. You suspect a A- fractured lunate. B- fractured distal radius (Colles fracture). C- mid-radial fracture. D- dislocated first carpometacarpal joint. E- dislocated midcarpal joint.

B- fractured distal radius (Colles fracture).

The cervicoaxillary canal: A- forms the base of the axilla. B- is bounded by the first rib, clavicle, and superior edge of the scapula. C- conducts the subclavian artery. D- leads to the quadrangular space. E- is occluded in a shoulder dislocation.

B- is bounded by the first rib, clavicle, and superior edge of the scapula.

Following an avulsion fracture of the greater tubercle of the humerus, the humerus would primarily be: A- laterally rotated B- medially rotated C- abducted D- flexed E- extended

B- medially rotated

You examine a patient who is an avid bicycle rider. He complains of sensory loss on the medial side of his hands and you find some weakness in his intrinsic hand muscles. You suspect that: A- the patient used a hand posture that put excessive pressure on the superficial branch of his radial nerve. B- the patient used a hand posture that put excessive pressure on his ulnar nerve. C- repetitive wrist flexion and extension that occurred with braking caused swelling of long flexor tendons at the wrist. D- the patient's flexed trunk but extended neck posture during riding stressed his neck vertebrae so that osteophytes developed reducing the size of his C8/T1 intervertebral foramen. E- the patient probably has a cervical rib and that extended periods in the riding position resulted in inflammation around the nerves surrounding this structure.

B- the patient used a hand posture that put excessive pressure on his ulnar nerve.

You are assisting in the emergency room when the attending physician examines a patient after an elbow injury. The physician holds the proximal interphalangeal joint of the little finger and asks the patient to flex the distal phalanx. This procedure tests the functionality of what nerve? A- radial B- ulnar C- median D- posterior interosseous E- anterior interosseous

B- ulnar

Which of the following reasons best explains why it is easier to do a "chin-up" (hands supinated) than a "pull-up" (hands pronated)? A. Because the brachialis is a less-effective elbow flexor in the pronated position. B. Because the biceps is a less-effective flexor in the pronated position. C. Because the brachioradialis is a less-effective flexor in the pronated position. D. Because the long digital flexors can better assist with elbow flexion in the supinated position. E. Because the humero-radial-ulnar joint is better aligned in the supinated position.

B. Because the biceps is a less-effective flexor in the pronated position.

A laceration of the thenar eminence that results in complete section of the recurrent branch of the median nerve would result in: A. claw hand. B. ape hand. C. loss of all ability to abduct the thumb. D. loss of all ability to adduct the thumb. E. loss of all ability to flex the metacarpophalangeal joint of the thumb.

B. ape hand > no opposition of thumb

Following a left radical mastectomy, a woman is unable to abduct her arm more than 90 degrees. Which of the following structures do you suspect was injured during the surgical procedure? A. dorsal scapular nerve B. long thoracic nerve C. suprascapular nerve D. serratus posterior superior muscle E. rotator cuff component of the shoulder joint capsule

B. long thoracic nerve > serratus anterior

Which of the following is incorrect pertaining to the axillary vein? A- If lacerated in the axilla, there is a risk of producing an air embolus. B- It is the vessel that is actually punctured in a typical "subclavian" vein puncture for catheter insertion. C- It lies deep to the axillary artery as the vessels cross the 1st rib. D- It is formed by the union of the brachial and basilic veins.

C- It lies deep to the axillary artery as the vessels cross the 1st rib

The ridge indicated by the arrow in the following photograph overlies the tendon of which of the following muscles? A- palmaris longus B- palmaris brevis C- flexor carpi radialis D- flexor digitorum superficialis E- abductor pollicis longus

C- flexor carpi radialis

Which of the following would not be associated with a complete section of the ulnar nerve at the wrist? A- inability to abduct the little finger B- inability to grasp a piece of paper between the extended 4th and 5th digits C- inability to flex the metacarpophalangeal joint while extending interphalangeal joints of the 2nd digit D- clawhand E- loss of all sensation on the palmar aspect of the little finger

C- inability to flex the metacarpophalangeal joint while extending interphalangeal joints of the 2nd digit > median nerve

During an axillary lymph node dissection, a resident cleans the space between the pectoralis major and minor muscles, in an attempt to remove all of the lateral pectoral lymph nodes. Upon recovery it is noted that the patient's lower pectoralis major is paralyzed. The nerve most likely injured is the: A- Axillary nerve B- lateral pectoral nerve C- medial pectoral nerve D- suprascapular nerve E- thoracodorsal nerve

C- medial pectoral n. ( medial cord, C8, T1)

A man is struck by the sharp edge of a metal panel across the anterior surface of his right arm at midlength and the impact severs all of the tissue to the bone. When examined in the emergency room it is noted that the patient can only weakly flex his elbow and the lateral side of his forearm is numb. In addition to the muscles, which nerve is injured? A- axillary B-median C- musculocutaneous D- radial E- ulnar

C- musculocutaneous *Weak flexion by brachiradialis> radial nerve Entrapment by coracobrachialis can affect nerve

If the brachial artery is ligated at its origin, which of the following arteries would supply blood to the profunda brachii artery? A-anterior circumflex humeral artery B- scapular circumflex artery C- posterior circumflex humeral artery D- middle collateral artery E- superior ulnar collateral artery

C- posterior circumflex humeral artery

A 34-year-old secretary complains of tingling of her right index and middle fingers over 2 months' duration. She notes some weakness of her right hand and has begun to drop items such as her coffee cup. Which of the intrinsic muscles of the hand is paralyzed? A-palmar interossei B-dorsal interossei C-lateral two lumbricals D-Adductor pollicis E-flexor pollicis longus

C-lateral two lumbricals median nerve compression in carpal tunnel pain, "pins and needles", paresthesia, and/or numbness over the palmar surface of the lateral 3½ digits weakness (paresis) or paralysis and atrophy of thenar muscles and first 2 lumbrical muscles

In the ER you examine a young girl who is "protecting" her right upper limb by holding it while maintaining the elbow flexed and forearm pronated. The patient's father related that he inadvertently jerked her up by the hand to lift her onto the bus. You suspect: A. a ruptured biceps tendon. B. a ruptured pectoralis major tendon. C. a dislocated (subluxed) radial head. D. an avulsed lesser tubercle. E. an avulsed medial humeral condyle.

C. a dislocated (subluxed) radial head.

Which of the following statements is incorrect pertaining to the extensors carpi radialis longus and brevis muscles? A- When only the two muscles act together, wrist extension and abduction is produced. B- When the two muscles act with the extensor carpi ulnaris, only wrist extension is produced. C- When the two muscles act with the flexor carpi ulnaris, only wrist abduction is produced. D One of the muscles is innervated by the ulnar nerve and the other by the deep branch of the radial nerve. E- Both attach to the humerus.

D- One of the muscles is innervated by the ulnar nerve and the other by the deep branch of the radial nerve. > radial (ECRL) & deep br of radial (ECRB)

A 52 year-old woman falls on her out-stretched hand and fractured her scaphoid bone. It is most likely accompanied by a rupture of the following artery: A- Ulnar artery B-Deep palmar arch C- anterior interosseus artery D- Radial artery E- Princeps pollicis artery

D- Radial artery (snuff box)

A patient cannot raise his arm above the horizontal and exhibit the abnormal condition shown in the following photograph. Which structure of the brachial plexus would most likely damaged? A- Medial cord B- Posterior cord C- Lower trunk D- Roots E- Upper trunk

D- Roots > serratus anterior > long thoracic nerve (roots C5-C7) Winged Scapula

Which of the following relationships at the wrist is incorrect? A- The median nerve lies deep to the tendon of the palmaris longus. B- The ulnar artery and nerve lie lateral to the tendon of the flexor carpi ulnaris. C- The radial artery can be compressed against the radius. D- The radial artery lies medial to the tendon of the flexor carpi radialis. E- The scaphoid can be palpated in the floor of the anatomical snuffbox.

D- The radial artery lies medial to the tendon of the flexor carpi radialis.

Which of the following is incorrect pertaining to the anatomic "snuffbox"? A- It is bounded anteriorly by the tendons of abductor pollicis longus and extensor pollicis brevis. B- It is bounded posteriorly by the tendon of extensor pollicis longus. C- The radial artery traverses its floor. D- The superficial branch of the radial nerve emerges from it. E- The radial styloid process can be palpated within it.

D- The superficial branch of the radial nerve emerges from it > pass over

You examine a young male patient whose shoulder was injured during a football game. You immediately notice that his acromion process is abnormally prominent and inferior to the acromial end of the clavicle. You diagnose: A- an anteriorly dislocated glenohumeral joint B- a posteriorly dislocated glenohumeral joint C- a dislocated acromioclavicular joint with intact coracoclavicular ligaments D- a dislocated acromioclavicular joint with torn coracoclavicular ligaments E- a torn rotator cuff

D- a dislocated acromioclavicular joint with torn coracoclavicular ligaments

A ten-year old girl falls off her bike and has difficulty moving her shoulder. Her radiogram & angiogram taken in the ER reveal a fracture of the surgical neck of her humerus and bleeding from the point of fracture. Which artery and nerve are most likely affected? A- axillary nerve & circumflex scapular artery B- radial nerve & posterior circumflex humeral artery C- radial nerve & circumflex scapular artery D- axillary nerve & posterior circumflex humeral artery E- radial nerve & brachial artery

D- axillary nerve & posterior circumflex humeral artery (quadrangular space)

What is the correct order of structures in the cubital fossa from lateral to medial? A- brachial artery, median nerve, biceps tendon B- brachial artery, biceps tendon, median nerve C- median nerve, brachial artery, biceps tendon D- biceps tendon, brachial artery, median nerve E- biceps tendon, median nerve, brachial artery

D- biceps tendon, brachial artery, median nerve

Following a knife wound to the neck, you notice that the medial border of a patient's left scapula is located further from the midline than that of his right scapula. The nerve most likely injured by the wound is the: A- long thoracic B- medial pectoral C- suprascapular D- dorsal scapular E- superior subscapular

D- dorsal scapular > rhomboids> roots C5 Other condition that affect nerve: entrapment within scalenus muscle

A young girl presents with a right small forearm and a weak grasp. On the same side, you observed a dropping of the eyelid and constriction of the pupil. Your exam should show: A- weakness of opponent pollicis B- paralysis of extensor digitorum C- weakness of lumbrical 2 & 3 D- paralysis of palmar interossei E- weakness of flexor digitorum superficialis

D- paralysis of palmar interossei > ulnar n. (C8, T1) Lower brachial plexus: *Klumpke's palsy* lower brachial plexus lesion (C8-T1) usually results when upper limb is forcefully jerked upward (e.g., grabbing a tree limb to break a fall or during difficult delivery) from a forceful upward pull on the extremity or a Pancoast tumor (at the apex of the lung) weakness of wrist and finger flexion, paralysis of intrinsic hand muscles claw-hand deformity: MP joints of digits 4-5 hyperextended with the IP joints flexed as in ulnar nerve lesion *Horner syndrome* (constricted pupil (miosis) & a weak, droopy eyelid (ptosis)) may be present due to damage to sympathetic nerves (T1 level of spinal cord)

Damage to the posterior cord of the brachial plexus can affect the function of the following muscles except A- deltoid B-latissimus dorsi C- teres minor D- pectoralis minor E-subscapularis

D- pectoralis minor > medial pectoral nerve from medial cord

The cephalic vein: A- becomes the brachial vein. B- becomes the axillary vein. C- originates on the medial side of the dorsal venous network at the wrist. D- pierces the clavipectoral fascia. E- empties into the subclavian vein.

D- pierces the clavipectoral fascia.

"Wrist-drop" is associated with: A- unopposed action of the lumbricals and interossei. B- rupture of the extensor digitorum. C- avulsion of the olecranon. D- section of the radial nerve at the mid- humeral level. E- section of the superficial branch of the radial nerve.

D- section of the radial nerve at the mid-humeral level > affects wrist extensors in forearm

After a penetrating wound in the area of the posterior axillary fold a patient had weakness in extension and adduction of the arm. Which nerve is most likely involved? A-long thoracic nerve B-upper subscapular nerve C- dorsal scapular nerve D- thoracodorsal nerve E- suprascapular nerve

D-thoracodoral n. (posterior cord, C6-8) > Latissimus dorsi

You examine a patient who has a condition in which each time his index finger is flexed and extended, there is an audible "snap." Which of the following is the likely cause of this "trigger finger?" A. infection in the midpalmar space B. osteoarthritis of the metacarpophalangeal joint C.carpal tunnel syndrome D. thickening of the fibrous digital sheath and swelling of the flexor tendons E. calcification of the origin of the lumbrical muscle

D. thickening of the fibrous digital sheath and swelling of the flexor tendons

A 22-year-old man is involved in a motor vehicle accident. The patient suffered multiple injuries including a displaced fracture of the left humerus. He complains of an inability to open his left hand and loss of sensation on a portion of his left hand. Name the diagnosis for this injury and explain its mechanisms.

Diagnosis: *Wrist drop* (no extension of wrist )> hand is flexed Mechanisms: Damage to radial nerve in radial groove Motor deficits: weaken arm extension, paralysis of forearm extensors of wrist (hand flexed), weaken abductors & adductors of wrist, weaken supination, flexed digits Sensory deficits: Lateral dorsum of hand and dorsal surface of the lateral 3½ digits, except over the distal phalanges & small portion of lateral palm

Dupuytren contracture refers to: A- an abnormal spasticity in the flexor digitorum profundus tendons. B- an abnormal spasticity in the flexor pollicis longus tendons. C- a tightening of the flexor retinaculum that results in carpal tunnel syndrome. D- a tightening of the anterior skin of the hand, resulting in reduced mobility and an increase depth in the skin creases. E- a shortening and thickening of the palmar fascia of the hand, resulting in partial flexion of the digits.

E- a shortening and thickening of the palmar fascia of the hand, resulting in partial flexion of the digits.

The suprascapular nerve may be trapped and compressed as it passes through the spinoglenoid notch. The patient will have the most difficulty with A- Initiating adduction B- extension of the arm C- medial rotation of the arm D- Initiating abduction E- lateral rotation of the arm

E- lateral rotation of the arm > infraspinatus > supraspinatus nerve

Which of the following would not be associated with a complete section of the median nerve at the elbow? A- inability to flex both the proximal and the distal interphalangeal joints of digits 2 and 3 B- atrophy of thenar eminence muscles C- greatly weakened pronation D- loss of sensation on the lateral aspect of the palmar surface of the hand E- loss of ability to adduct the thumb

E- loss of ability to adduct the thumb (ulnar nerve)

Which of the following is incorrect pertaining to the pronator quadratus? A. It is innervated by the anterior interosseous branch of the median nerve. B. It is the prime mover for pronation. C. It initiates the movement of pronation. D. It helps maintain the integrity of the interosseous membrane between the radius and ulna when upward thrusts are transmitted through the wrist. E. It can be palpated by deeply pressing an index finger two-thirds of the proximal-distal length of the forearm, at the middle of its ventral surface.

E. It can be palpated by deeply pressing an index finger two-thirds of the proximal-distal length of the forearm, at the middle of its ventral surface.