MCQs of Anatomy of Axilla, Posterior Shoulder, & Arm

MCQs of Anatomy of Axilla, Posterior Shoulder, & Arm

axillary_artery
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  1. During a fight a man is stabbed in the lateral chest beneath the right arm. The wound does not enter the chest cavity. Physical examination reveals that the vertebral (medial) border of the patient’s scapula projects posteriorly and is closer to the midline on the injured side. On return visit the patient complains that he cannot reach as far forward (such as to reach for a door knob) as he could before the injury. The nerve injured which caused these symptoms is the:
    axillary
    long thoracic
    musculocutaneous
    radial
    suprascapular
    Ans: B
  2. A man suffers a penetrating wound through the anterior axillary fold, with resulting damage to one of the main terminal branches of the brachial plexus. Among the effects is a significant weakening of flexion of the elbow. One or more other effects to be expected is (are):
    Loss of cutaneous sensation on the tips of several fingers
    Only loss of cutaneous sensation on the anterolateral surface of the forearm
    Only weakening of flexion at the shoulder
    Weakening of flexion at the shoulder and loss of cutaneous sensation on the anterolateral surface of the arm
    Weakening of flexion at the shoulder and loss of cutaneous sensation on the anterolateral surface of the forearm
    Ans: E
  3. A person sustains a left brachial plexus injury in an auto accident. After initial recovery the following is observed: 1) the diaphragm functions normally, 2) there is no winging of the scapula, 3) abduction cannot be initiated, but if the arm is helped through the first 45 degrees of abduction, the patient can fully abduct the arm. From this amount of information and your knowledge of the formation of the brachial plexus where would you expect the injury to be:
    axillary nerve
    posterior cord
    roots of plexus
    superior trunk
    suprascapular nerve
    Ans: E
  4. The cords of the brachial plexus are:
    above the clavicle, medial to the scalenus anticus (anterior scalene).
    above the clavicle, behind the scalenus anticus (anterior scalene).
    at or below the clavicle, closely related to the axillary artery.
    at or below the clavicle, closely related to the axillary vein.
    Ans: C
  5. An open arterial anastomosis in the shoulder occurs between the suprascapular artery and which other artery?
    Anterior circumflex humeral
    Circumflex scapular
    Dorsal scapular
    Thoracodorsal
    Transverse cervical
    Ans: B
  6. The long thoracic nerve innervates which muscle?
    Anterior scalene
    Middle scalene
    Serratus anterior
    Teres major
    Subscapularis
    Ans: C
  7. A man riding a motorcycle hit a wet spot in the road, lost control, and was thrown from his bike. He landed on the right side of his head and the tip of his shoulder, bending his head sharply to the left and stretching the right side of his neck. Subsequent neurological examination revealed that the roots of the 5th and 6th cervical nerves had been torn away from the spinal cord.

    Following the above injury, which of the movements of the arm at the shoulder would you expect to be totally lost?
    adduction
    abduction
    flexion
    extension
    medial rotation
    Ans: B

  8. Following the above injury there would most likely be diminished cutaneous sensation over what part of the upper limb?
    the back of the shoulder
    the pectoral region
    the top of the shoulder and the lateral side of the arm
    the medial side of the arm and forearm
    the tip of the little finger
    Ans: C
  9. A patient is found to have a melanoma (cancer arising in pigment cells) originating in the skin of the left forearm. After removal of the tumor from the forearm, all axillary lymph nodes lateral to the medial edge of the pectoralis minor muscle are removed.
    Which axillary lymph nodes would not be removed by this procedure?
    Apical
    Central
    Lateral
    Pectoral
    Subscapular
    Ans: A
  10. Postoperative examination revealed that the medial border and inferior angle of the left scapula became unusually prominent (projected posteriorly) when the arm was carried forward in the sagittal plane, especially if the patient pushed with outstretched arm against heavy resistance (e.g., a wall). What muscle must have been denervated during the axillary dissection?
    Levator scapulae
    Pectoralis major
    Rhomboideus major
    Serratus anterior
    Subscapularis
    Ans: D
  11. During a motorcycle accident, an 18-year-old male landed on the right lateral side of his rib cage with his right upper limb abducted. In the hospital he was found to have “winging” of the right scapula. Which nerve was likely damaged in the accident?
    Accessory
    Lateral pectoral
    Long thoracic
    Phrenic
    Vagus
    Ans: C
  12. During an industrial accident, a sheet metal worker lacerates the anterior surface of his wrist at the junction of his wrist and hand. Examination reveals no loss of hand function, but the skin on the thumb side of his palm is numb. Branches of which nerve must have been severed?
    Lateral antebrachial cutaneous
    Medial antebrachial cutaneous
    Median
    Radial
    Ulnar
    Ans: C
  13. The nerve which passes through the quadrangular space of the posterior shoulder innervates which muscle?
    Deltoid
    Infraspinatus
    Subscapularis
    Supraspinatus
    Teres major
    Ans: A
  14. You are in the emergency room when a patient is brought in, the loser in a street fight. He has received a stab wound about 1.5 cm long in the right side of the chest about 1.5 cm below and 1 cm medial to the coracoid process of the scapula. He has lost a lot of bright red blood from a large (approx. 1.2 cm in diameter) severed artery found deep at this location. Intravenous fluids are immediately administered and a surgeon is called in to repair the artery. He begins by making an incision through the skin and subcutaneous tissue just below the clavicle, then cuts the clavicular head of the pectoralis major muscle and retracts it downward to obtain sufficient exposure of the area. He next encounters a partially severed muscle running downward and medially from the coracoid process. He divides the remaining fibers of the muscle and has you retract it downward. This exposes a bloody fat-filled space full of vessels and nerves.

    Which space or cavity was opened when the surgeon reflected the muscles
    axillary space
    infraspinatous fossa
    quadrangular space
    subdeltoid bursa
    triangular space
    Ans: A

  15. The surgeon next encounters a large (about 2 cm in diameter) horizontally running vein, fortunately intact, which is also retracted downward. This exposes the damaged artery. He knows that the cords of the brachial plexus are closely associated with this artery, so he carefully retracts one found superolateral and one found inferomedial to the artery and then proceeds to repair the artery itself and close the wound.

    The large artery that was severed was the:
    axillary
    brachial
    radial
    subscapular
    suprascapular
    Ans: A

  16. Later when you see the patient it is clear that he has pronounced neurological deficits. There is lack of cutaneous sensation between his thumb and index finger on the dorsal side, diminished sensation on the dorsal surface of the forearm, arm, and lateral side of the shoulder. He has “wrist drop” (inability to extend the wrist), lack of extension at the elbow, and although abduction can be initiated, it cannot be completed. Flexion, extension, medial and lateral rotation of the arm are not significantly affected. There is no “winging of the scapula.” Later exploration by a neurosurgeon reveals that a single large nerve bundle posterior to the artery was also severed, accounting for the neurological findings
    The large nerve bundle lying posterior to the artery which was also severed was the:
    C 7 root
    middle trunk
    posterior cord
    posterior division
    radial nerve
    Ans: C
  17. Neurological testing of a patient reveals no cutaneous sensation on the tip of the index finger. Such a finding would indicate injury to some portion of which nerve?
    axillary
    median
    musculocutaneous
    radial
    ulnar
    Ans: B
  18. You are attending an axillary lymph node dissection in a patient with a melanoma in the upper limb. The surgeon says, “We are going to sample the level II lymph nodes posterior to the pectoralis minor muscle.” Having excelled in anatomy, you realize that she is referring to the anatomical nodes known as
    apical axillary nodes
    central axillary nodes
    lateral axillary nodes
    lateral pectoral nodes
    subscapular axillary nodes
    Ans: B
  19. In the axilla the pectoralis minor is a landmark, being closely related to all of the following structures except:
    cephalic vein
    cords of the brachial plexus
    lateral thoracic artery
    medial pectoral nerve
    second part of the axillary artery
    Ans: A
  20. In a patient with Erb-Duchenne palsy, a nerve arising from the superior trunk of the brachial plexus is nonfunctional. This nerve is the:
    Suprascapular
    Dorsal scapular
    Long thoracic
    Lateral pectoral
    Medial pectoral
    Ans: A
  21. The axillary nerve arises directly from which part of the brachial plexus?
    inferior trunk
    lateral cord
    medial cord
    middle trunk
    posterior cord
    superior cord
    Ans: E
  22. Which of the following is not a direct branch of the axillary artery?
    anterior circumflex humeral
    posterior circumflex humeral
    thoracoacromial
    thoracodorsal
    subscapular
    Ans: D
  23. While putting metal panels on the roof of a barn, one of the panels slips out of the hands of the man on the roof. During an attempt to catch the panel, a worker below is struck by its sharp edge. The panel hits 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?
    axillary
    median
    musculocutaneous
    radial
    ulnar
    Ans: C
  24. While treating the patient (in the preceding question) the doctor observes, “You were fortunate that the panel did not sever the large artery running down the medial side of your arm.” The large artery referred to lies in the neurovascular compartment and supplies most everything below the elbow; this artery is the:
    axillary
    brachial
    deep brachial
    radial
    ulnar
    Ans: B
  25. In a case of Erb’s palsy, where roots C5 and C6 of the brachial plexus are avulsed (torn out) which muscle is paralyzed?
    Latissimus dorsi
    Pectoralis minor
    Supraspinatus
    Trapezius
    Triceps brachii
    Ans: C
  26. If the second part of the axillary artery was interrupted, collateral blood flow could pass from branches of the thyrocervical trunk into which artery?
    Anterior humeral circumflex
    Circumflex scapular
    Deep brachial
    Posterior humeral circumflex
    Thoracoacromial
    Ans: B
  27. In a fracture of the surgical neck of the humerus, which artery may be injured?
    Subscapular
    Posterior humeral circumflex
    Radial recurrent
    Deep brachial
    Circumflex scapular
    Ans: B
  28. While riding a bike, a patient fell against a tree and fractured the shaft of the humerus at midlength. What nerve may be injured because of its close proximity to the injury?
    Ulnar
    Radial
    Axillary
    Medial antebrachial cutaneous
    Median
    Ans: B
  29. Loss of sensation from the tip of the index finger is indicative of injury to which nerve?
    Radial
    Median
    Ulnar
    Musculocutaneous
    Medial antebrachial cutaneous
    Ans: B
  30. In a fracture of the midshaft of the humerus, which artery is most likely to be injured?
    Subscapular
    Posterior circumflex humeral
    Radial recurrent
    Deep brachial
    Circumflex scapular
    Ans: D
  31. As an inexperienced phlebotomist (blood drawer) attempts to insert the needle to draw blood from the median cubital vein, the patient suddenly screams and complains of pain and burning in the middle and thumb side of his palm. The nerve accidentally impaled on the needle was the
    lateral antebrachial cutaneous
    medial antebrachial cutaneous
    median
    ulnar
    posterior antebrachial cutaneous
    radial
    superficial radial
    Ans: C
  32. In a diving accident that severed the spinal cord below the sixth cervical vertebra, which muscle would be affected?
    Deltoid
    Infraspinatus
    Latissimus dorsi
    Levator scapulae
    Trapezius
    Ans: C
  33. Which muscle is the strongest medial rotator of the arm?
    Coracobrachialis
    Infraspinatus
    Subscapularis
    Supraspinatus
    Teres minor
    Ans: C
  34. An elderly man complained of pain in his shoulder when he brought his forearm and hand behind his back while dressing. It was determined that the pain was caused by stretching of the lateral rotators of his arm during this motion. Which muscle was most likely involved?
    Infraspinatus
    Latissimus dorsi
    Subscapularis
    Supraspinatus
    Teres major
    Ans: A
  35. A woman riding a mountain bike on a rough trail hits a rut and is thrown from the bike. Her upper arm hits a tree, fracturing the humerus just above the insertion of the teres major muscle. Later, during examination, it is noted that she cannot extend her forearm at the elbow or hand at the wrist. Which nerve must have been injured?
    Axillary
    Median
    Musculocutaneous
    Radial
    Ulnar
    Ans: D
  36. In old age, the supraspinatus tendon is sometimes ruptured where it blends with the capsule of the shoulder joint. Following this kind of injury one might expect
    difficulty in adducting the arm
    difficulty in flexing the arm
    difficulty in abducting the arm
    difficulty in extending the arm
    difficulty in medially rotating the arm
    Ans: C
  37. During a strenuous game of tennis a 55 year old woman complained of severe shoulder pain that forced her to quit the game. During physical examination it was found that she could not initiate abduction of her arm, but if her arm was elevated to 45 degrees from the vertical (at her side) position, she had no trouble fully abducting it. Injury to which muscle was responsible?
    deltoid
    infraspinatus
    supraspinatus
    teres major
    trapezius
    Ans: C
  38. A man is in an auto accident and sustains several injuries, among them are:
    1. Skin lacerations:
      • on the back of his head in the occipital area,
      • on his chest just above the nipple,
      • on the lateral side of his arm,
      • lateral forearm at midlength,
      • dorsal hand between his thumb and index finger.
    2. Abrasions and contusions (bruises) about his right shoulder
    3. A fractured right radius near its distal end

    Later, while undergoing physical therapy because of his shoulder injury, he comments that it is very painful when his forearm is brought across his chest (medial or internal rotation of the humerus). You deduce that the pain is due to stretching of the lateral (external) rotators of the shoulder. Which muscle was most likely the source of his pain?
    infraspinatus
    latissimus dorsi
    rhomboideus major
    supraspinatus
    teres major
    Ans: A

  39. An elderly patient complains of shoulder pain and has difficulty abducting his arm. Arthroscopy is done in which a dye is injected into the shoulder joint and an X-ray taken. The radiologist notes that the dye has leaked from the shoulder joint into the subacromial bursa. What tendon would need to be ruptured for this to occur?
    deltoid
    infraspinatus
    latissimus dorsi
    supraspinatus
    teres minor
    Ans: D
  40. A person riding a mountain bike on a rustic trail hits a rut, the fork of the bike breaks and the person is thrown into a tree, severely fracturing the upper end of his humerus. During the repair the surgeon ties off the artery traveling through the quadrangular space to stop the hemorrhage. Which artery did he ligate?
    dorsal scapular
    posterior circumflex humeral
    scapular circumflex
    subscapular
    suprascapular
    Ans: B
  41. After initial examination, a patient is sent to radiology. Radiographs reveal that the portion of the scapula forming the tip or point of the shoulder has been fractured. This bone is the
    acromion
    angle
    coracoid
    glenoid
    spine
    Ans: A
  42. Several deficits in muscle function of the right upper limb were noted, including inability to abduct the arm. This was caused by denervation of which muscle?
    deltoid
    infraspinatus
    latissimus dorsi
    teres minor
    trapezius
    Ans: A
  43. The rotator cuff is composed of all of the following muscles except:
    infraspinatus
    subscapularis
    supraspinatus
    teres major
    teres minor
    Ans: D
  44. Following a gunshot wound to the shoulder, a patient is unable to abduct the arm between 0 and 15 degrees, with reduced lateral rotation of the humerus. What nerve is probably injured?
    Accessory (CN XI)
    Axillary
    Median
    Suprascapular
    Ulnar
    Ans: D
    A scaffold falls on the right shoulder of a construction worker lacerating the side of his neck and suprascapular area, severing C5 spinal nerve just lateral to the vertebral column. Subsequent to the injury, the patient could not elevate the tip of his shoulder or retract it and had difficulty fully abducting his arm. Given this scenario answer the following questions.
  45. Due to the bleeding, the surgeon ligated (tied off) the suprascapular artery as it crossed the top of the scapula. There was no concern however, as she knew that direct collateral branches of which artery would supply the normal distribution of the suprascapular artery.
    anterior circumflex humeral
    posterior circumflex humeral
    scapular circumflex
    subscapular
    thoracodorsal
    Ans: C
  46. The patient was unable to retract his scapula because of paralysis of the trapezius and
    infraspinatus
    levator scapulae
    rhomboids
    serratus posterior superior
    supraspinatus
    Ans: C
  47. Would there be loss of cutaneous sensation over the shoulder due to loss of the nerves supplying the C5 dermatome?
    Yes
    No
    Ans: A
  48. When the C5 spinal nerve was severed were any preganglionic sympathetic fibers cut?
    Yes
    No
    Ans: B




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