1.
A 22-year-old man presented to his family
physician with a laceration of the fi brous
sheets or bands that cover his body under
the skin and invest the muscles. Which of
the following structures would most likely
be injured?
Correct Answer
B. Facia
Explanation
The correct answer is Facia. The fibrous sheets or bands that cover the body under the skin and invest the muscles are called fascia. If a person has a laceration in this area, it is most likely that the fascia would be injured.
2.
A 46-year-old male patient with high
blood pressure was examined in the emergency
department, and his physician found
a leakage of blood from the blood vessel that
normally carries richly oxygenated blood.
Which of the following vessels would most
likely be damaged?
Correct Answer
C. Pulmonary veins
Explanation
The pulmonary veins carry oxygenated blood from the lungs back to the heart. In a healthy individual, these veins should not have any leakage of blood. Therefore, if a leakage of blood is found in a patient, it suggests that the pulmonary veins are damaged. This is the most likely vessel to be damaged in this scenario.
3.
A 33-year-old male patient complains of
feeling severe pain when he tries to turn
his neck. A physician realizes that the
problem is in his pivot (trochoid) joint.
Which of the following joints would most
likely be examined?
Correct Answer
B. Atlantoaxial joint
Explanation
The physician would most likely examine the Atlantoaxial joint. The patient's complaint of severe pain when turning his neck suggests a problem with the joint responsible for rotation between the atlas (C1) and axis (C2) vertebrae, which is the Atlantoaxial joint. This joint allows for the majority of rotational movement in the neck, and dysfunction or injury in this area can cause severe pain and limited range of motion.
4.
A 21-year-old patient has a lesion of the
upper trunk of the brachial plexus (Erb–
Duchenne paralysis). Which of the following
is the most likely diagnosis?
Correct Answer
C. Arm tending to lie in medial rotation
Explanation
The most likely diagnosis for a 21-year-old patient with a lesion of the upper trunk of the brachial plexus (Erb-Duchenne paralysis) is an arm tending to lie in medial rotation. This is because the upper trunk of the brachial plexus innervates the muscles responsible for external rotation of the arm, and when this is affected, the unopposed action of the internal rotators causes the arm to lie in a medial rotation position.
5.
A patient comes in with a gunshot wound
and requires surgery in which his thoracoacromial
trunk needs to be ligated. Which of
the following arterial branches would maintain
normal blood fl ow?
Correct Answer
E. Superior thoracic
Explanation
The superior thoracic artery would maintain normal blood flow if the thoracoacromial trunk is ligated during surgery. The thoracoacromial trunk is a major branch of the axillary artery, and it gives rise to several arteries including the acromial, pectoral, clavicular, and deltoid arteries. Ligation of the thoracoacromial trunk would cut off blood supply to these branches, but the superior thoracic artery, which is a separate branch of the axillary artery, would still provide blood flow to the area.
6.
A 27-year-old patient presents with an
inability to draw the scapula forward and
downward because of paralysis of the pectoralis
minor. Which of the following would
most likely be a cause of his condition?
Correct Answer
C. Fracture of the coracoid process
Explanation
Paralysis of the pectoralis minor, which is responsible for drawing the scapula forward and downward, is most likely caused by a fracture of the coracoid process. The coracoid process is a bony projection of the scapula that serves as an attachment site for the pectoralis minor muscle. If the coracoid process is fractured, it can disrupt the attachment of the pectoralis minor, leading to paralysis of the muscle and the inability to draw the scapula forward and downward.
7.
A 22-year-old patient received a stab
wound in the chest that injured the intercostobrachial
nerve. Which of the following
conditions results from the described lesion
of the nerve?
Correct Answer
D. Loss of sensory fi bers from the second
intercostal nerve
Explanation
The intercostobrachial nerve is responsible for providing sensory fibers to the lateral aspect of the arm. Therefore, if this nerve is injured, it would result in a loss of tactile sensation on the lateral aspect of the arm. The other options are not related to the intercostobrachial nerve and are not consistent with the described lesion.
8.
A 16 year-old boy fell from a motorcycle,
and his radial nerve was severely damaged
because of a fracture of the midshaft of the
humerus. Which of the following conditions
would most likely result from this
accident?
Correct Answer
A. Loss of wrist extension leading to wrist
drop
Explanation
The radial nerve innervates the muscles responsible for wrist extension. In this case, the severe damage to the radial nerve due to the fracture of the midshaft of the humerus would result in the loss of function of these muscles. This loss of wrist extension leads to a condition called wrist drop, where the wrist cannot be extended and hangs in a flexed position. Therefore, the most likely result from this accident would be the loss of wrist extension leading to wrist drop.
9.
A patient comes in complaining that she
cannot fl ex her proximal interphalangeal
joints. Which of the following muscles
appear(s) to be paralyzed on further examination
of her fi nger?
Correct Answer
D. Flexor digitorum superficialis
Explanation
The patient's inability to flex her proximal interphalangeal joints suggests a paralysis of the flexor digitorum superficialis muscle. This muscle is responsible for flexing the middle phalanges of the fingers, which allows for flexion of the proximal interphalangeal joints. The other muscles listed, such as the palmar interossei, dorsal interossei, flexor digitorum profundus, and lumbricals, are not directly involved in flexing the proximal interphalangeal joints.
10.
A 21-year-old woman walks in with a
shoulder and arm injury after falling during
horseback riding. Examination indicates
that she cannot adduct her arm because of
paralysis of which of the following muscles?
Correct Answer
C. Latissmus Dorsi
Explanation
The correct answer is Latissimus Dorsi. The patient's inability to adduct her arm suggests paralysis of the Latissimus Dorsi muscle. The Latissimus Dorsi muscle is responsible for adducting and extending the arm at the shoulder joint. If this muscle is paralyzed, it would result in the inability to bring the arm towards the midline of the body.
11.
A 14-year-old boy falls on his outstretched
hand and has a fracture of the
scaphoid bone. The fracture is most likely
accompanied by a rupture of which of the
following arteries?
Correct Answer
D. Radial Artery
Explanation
When a 14-year-old boy falls on his outstretched hand and fractures his scaphoid bone, the fracture is most likely accompanied by a rupture of the radial artery. The scaphoid bone is located in the wrist, and the radial artery runs along the thumb side of the forearm and wrist. A fracture in this area can cause damage to the radial artery, leading to bleeding and potential complications.
12.
A 35-year-old man walks in with a stab
wound to the most medial side of the proximal
portion of the cubital fossa. Which of
the following structures would most likely be
damaged?
Correct Answer
E. Median nerve
Explanation
The most likely structure to be damaged in this scenario is the median nerve. The question mentions a stab wound to the most medial side of the proximal portion of the cubital fossa. The cubital fossa is located on the anterior aspect of the elbow, and the median nerve runs through this region. Therefore, a stab wound in this area could potentially injure the median nerve.
13.
A 12-year-old boy walks in; he fell out of
a tree and fractured the upper portion of his
humerus. Which of the following nerves are
intimately related to the humerus and are
most likely to be injured by such a fracture?
Correct Answer
C. Radial and axillary
Explanation
The humerus is located in the upper arm, and the nerves that are most closely related to this bone are the radial and axillary nerves. Therefore, a fracture of the upper portion of the humerus is most likely to injure these nerves.
14.
A man injures his wrist on broken glass.
Which of the following structures entering
the palm superfi cial to the fl exor retinaculum
may be damaged?
Correct Answer
D. Ulnar artery and ulnar nerve
Explanation
The ulnar artery and ulnar nerve are the structures that enter the palm superficial to the flexor retinaculum. Injuring the wrist on broken glass can potentially damage these structures. The other options mentioned do not enter the palm superficial to the flexor retinaculum and therefore would not be affected in this scenario.
15.
Use this to answer ques 15-19
A 62-year-old woman slips
and falls on the bathroom fl oor. As a result,
she has a posterior dislocation of the hip joint
and a fracture of the neck of the femur
15 Rupture of the ligamentum teres capitis
femoris may lead to damage to a branch of
which of the following arteries?
Correct Answer
C. Obtruator
Explanation
The rupture of the ligamentum teres capitis femoris may lead to damage to the obturator artery. The obturator artery is a branch of the internal iliac artery and supplies blood to the muscles and structures in the medial compartment of the thigh, including the hip joint. Damage to this artery can result in compromised blood supply to the affected area, leading to ischemia and potential complications.
16.
Fracture of the neck of the femur results
in avascular necrosis of the femoral head,
probably resulting from lack of blood supply
from which of the following arteries?
Correct Answer
D. Medial femoral circumflex
Explanation
Fracture of the neck of the femur can lead to avascular necrosis of the femoral head, which is caused by a lack of blood supply. The blood supply to the femoral head is mainly provided by the medial femoral circumflex artery. When the neck of the femur is fractured, it can disrupt the blood flow through this artery, resulting in avascular necrosis. Therefore, the fracture of the neck of the femur can lead to avascular necrosis of the femoral head due to the lack of blood supply from the medial femoral circumflex artery.
17.
If the acetabulum is fractured at its posterosuperior
margin by dislocation of the
hip joint, which of the following bones could
be involved?
Correct Answer
C. Illium
Explanation
If the acetabulum is fractured at its posterosuperior margin by dislocation of the hip joint, the bone that could be involved is the ilium. The ilium is one of the three bones that make up the acetabulum, along with the ischium and pubis. A fracture in this region can occur due to a traumatic injury or dislocation of the hip joint, which can result in damage to the ilium bone. The other options, including the pubis, ischium, sacrum, and head of the femur, are not directly involved in the formation of the acetabulum and are less likely to be affected by this specific type of fracture.
18.
The woman experiences weakness when
abducting and medially rotating the thigh
after this accident. Which of the following
muscles is most likely damaged?
Correct Answer
E. Gluteaus Minimus
Explanation
The woman experiences weakness when abducting and medially rotating the thigh after the accident. The gluteus minimus muscle is most likely damaged because it is responsible for these movements.
19.
The woman undergoes hip surgery. If all
of the arteries that are part of the cruciate
anastomosis of the upper thigh are ligated,
which of the following arteries maintains
blood fl ow?
Correct Answer
C. Superior gluteal
Explanation
The superior gluteal artery maintains blood flow in the upper thigh if all of the arteries that are part of the cruciate anastomosis are ligated.
20.
A 17-year-old boy with a stab wound
received multiple injuries on the upper part
of the arm and required surgery. If the brachial
artery were ligated at its origin, which
of the following arteries would supply blood to the profunda brachii artery?
Correct Answer
C. Posterior humeral circumfl ex
Explanation
If the brachial artery is ligated at its origin, the blood supply to the profunda brachii artery would be provided by the posterior humeral circumflex artery.
21.
An 18-year-old boy involved in an automobile
accident presents with arm that
cannot abduct. His paralysis is caused by
damage to which of the following nerves?
Correct Answer
A. Suprascapular and axillary
Explanation
The correct answer is Suprascapular and axillary. The suprascapular nerve innervates the supraspinatus and infraspinatus muscles, which are responsible for shoulder abduction. The axillary nerve innervates the deltoid muscle, which also contributes to shoulder abduction. Damage to both of these nerves would result in the inability to abduct the arm. Musculocutaneous and median nerves innervate muscles of the forearm, not the shoulder. Axillary and radial nerves innervate different muscles in the arm and do not control shoulder abduction. Median and ulnar nerves innervate muscles of the hand, not the shoulder.
22.
A 38-year-old homebuilder was involved
in an accident and is unable to supinate his
forearm. Which of the following nerves are
most likely damaged?
Correct Answer
D. Radial and musculocutaneous
Explanation
The radial nerve innervates the muscles responsible for forearm supination, while the musculocutaneous nerve innervates the muscles responsible for elbow flexion. Therefore, damage to both the radial and musculocutaneous nerves would result in the inability to supinate the forearm.
23.
A 31-year-old patient complains of sensory
loss over the anterior and posterior surfaces
of the medial third of the hand and the
medial one and one-half fi ngers. He is diagnosed
by a physician as having “funny bone”
symptoms. Which of the following nerves is
injured?
Correct Answer
D. Ulnar
Explanation
The ulnar nerve is responsible for providing sensory innervation to the medial third of the hand and the medial one and one-half fingers. This nerve is commonly referred to as the "funny bone" nerve because it can be easily irritated or injured, leading to symptoms such as sensory loss in the described areas.
24.
A 23-year-old woman who receives a
deep cut to her ring fi nger by a kitchen knife
is unable to move the metacarpophalangeal
joint. Which of the following pairs of nerves
was damaged?
Correct Answer
D. Ulnar and radial
Explanation
The ulnar and radial nerves were likely damaged because the woman is unable to move the metacarpophalangeal joint of her ring finger. The ulnar nerve innervates the muscles responsible for flexing the ring finger, while the radial nerve innervates the muscles responsible for extending the finger. Damage to both nerves would result in the inability to move the joint.
25.
A patient has a torn rotator cuff of the
shoulder joint as the result of an automobile
accident. Which of the following muscle tendons
is intact and has normal function?
Correct Answer
C. Teres major
Explanation
The teres major muscle tendon is intact and has normal function in a patient with a torn rotator cuff of the shoulder joint as a result of an automobile accident. This is because the teres major muscle is not part of the rotator cuff muscles. The rotator cuff muscles include the supraspinatus, subscapularis, infraspinatus, and teres minor.
26.
A 27-year-old man with cubital tunnel
syndrome complains of numbness and tingling
in the ring and little fi nger and back
and sides of his hand because of damage to
a nerve in the tunnel at the elbow. Which of
the following muscles is most likely to be
paralyzed?
Correct Answer
C. Two medial Lumbricals
Explanation
The two medial lumbrical muscles are most likely to be paralyzed in a 27-year-old man with cubital tunnel syndrome. Cubital tunnel syndrome is caused by compression or irritation of the ulnar nerve at the elbow, which can result in numbness and tingling in the ring and little finger and the back and sides of the hand. The ulnar nerve innervates the two medial lumbrical muscles, which are responsible for flexing the metacarpophalangeal joints and extending the interphalangeal joints of the ring and little fingers. Therefore, damage to the ulnar nerve in the cubital tunnel can lead to paralysis of these muscles.
27.
A patient bleeding from the shoulder
secondary to a knife wound is in fair condition
because there is vascular anastomosis
around the shoulder. Which of the following
arteries is most likely a direct branch of the
subclavian artery that is involved in the
anastomosis?
(A) Dorsal scapular artery
(B) Thoracoacromial artery
(C) Circumfl ex scapular artery
(D) Transverse cervical artery
(E) Suprascapular artery
Correct Answer
A. Dorsal scapular artery
Explanation
The correct answer is the Dorsal scapular artery. The patient is in fair condition because there is vascular anastomosis around the shoulder. The Dorsal scapular artery is a direct branch of the subclavian artery and is involved in the anastomosis. This artery helps to provide a collateral blood supply to the shoulder region, allowing for adequate blood flow even if there is bleeding from the shoulder due to a knife wound.
28.
A 31-year-old roofer walks in with tenosynovitis
resulting from a deep penetrated
wound in the palm by a big nail. Examination
indicates that he has an infection in the
ulnar bursa. This infection most likely
resulted in necrosis of which of the following
tendons?
Correct Answer
C. Tendon of the flexor digitorum profundus
Explanation
The infection in the ulnar bursa can lead to necrosis of the tendon of the flexor digitorum profundus. This is because the flexor digitorum profundus tendon runs through the ulnar bursa, and an infection in the bursa can spread to the tendon, causing tissue death (necrosis).
29.
A man is unable to hold typing paper
between his index and middle fi ngers. Which
of the following nerves was likely injured?
Correct Answer
C. Ulnar nerve
Explanation
The ulnar nerve is responsible for innervating the muscles that control the movements of the fingers and hand. It specifically controls the muscles that allow for the adduction and abduction of the fingers. In this scenario, the man is unable to hold the typing paper between his index and middle fingers, indicating a loss of adduction function. This suggests that the ulnar nerve, which controls the adductor muscles, is likely injured.
30.
Questions 30–34: A 20-year-old college student
receives a severe blow on the inferolateral side
of the left knee joint while playing football.
Radiographic examination reveals a fracture
of the head and neck of the fi bula.
30. Which of the following nerves is damaged?
Correct Answer
C. Common peroneal
Explanation
The common peroneal nerve is most likely damaged in this scenario because it innervates the muscles in the anterior compartment of the leg, which includes the muscles that dorsiflex the foot and extend the toes. Fractures of the head and neck of the fibula can result in compression or stretching of the common peroneal nerve, leading to motor and sensory deficits in the lower leg and foot. The other nerves listed do not innervate the muscles in the anterior compartment of the leg and are less likely to be affected by this specific injury.
31.
After injury to this nerve, which of the
following muscles could be paralyzed?
Correct Answer
C. Extensor hallucis longus
Explanation
After injury to the nerve mentioned, the Extensor hallucis longus muscle could be paralyzed.
32.
If the lateral (fibular) collateral ligament
is torn by this fracture, which of the following
conditions may occur?
Correct Answer
B. Abnormal passive adduction of the
extended leg
Explanation
If the lateral (fibular) collateral ligament is torn by this fracture, it would result in a loss of stability on the lateral side of the knee joint. This would lead to abnormal passive adduction of the extended leg, where the leg moves inward towards the midline of the body. This occurs because the torn ligament can no longer provide the necessary support to prevent this inward movement.
33.
Which of the following arteries could
also be damaged by this fracture?
Correct Answer
C. Anterior tibial
Explanation
The fracture mentioned in the question could potentially damage the anterior tibial artery.
34.
Which of the following conditions would
occur from this fracture?
Correct Answer
D. Anterior tibial compartment syndrome
Explanation
Anterior tibial compartment syndrome would occur from this fracture.
35.
A 47-year-old woman is unable to invert
her foot after she stumbled on her driveway.
Which of the following nerves are most likely
injured?
Correct Answer
B. Deep peroneal and tibial
Explanation
The deep peroneal nerve is responsible for dorsiflexion of the foot, which is the ability to invert the foot. The tibial nerve is responsible for plantarflexion of the foot. In this case, the woman is unable to invert her foot, suggesting that the deep peroneal nerve is injured. The tibial nerve may also be injured, as it is involved in the same movement.
36.
A patient with a deep knife wound in the
buttock walks with a waddling gait that is
characterized by the pelvis falling toward
one side at each step. Which of the following
nerves is damaged?
Correct Answer
C. Superior gluteal nerve
Explanation
The superior gluteal nerve is responsible for innervating the gluteus medius, gluteus minimus, and tensor fasciae latae muscles. These muscles help to stabilize the pelvis during walking and maintain a level pelvis. If the superior gluteal nerve is damaged, the gluteus medius and minimus muscles will be weakened or paralyzed, causing the pelvis to fall toward the unaffected side during walking. This results in a waddling gait, as described in the question.
37.
A patient presents with sensory loss on
adjacent sides of the great and second toes
and impaired dorsifl exion of the foot. These
signs probably indicate damage to which of
the following nerves?
Correct Answer
C. Deep peroneal
Explanation
The patient's symptoms of sensory loss on adjacent sides of the great and second toes and impaired dorsiflexion of the foot indicate damage to the deep peroneal nerve. The deep peroneal nerve innervates the muscles that control dorsiflexion of the foot and also provides sensory innervation to the adjacent sides of the great and second toes.
38.
A 52-year-old woman slipped and fell
and now complains of being unable to
extend her leg at the knee joint. Which of the
following muscles was paralyzed as a result
of this accident?
Correct Answer
D. Quadriceps femoris
Explanation
The correct answer is Quadriceps femoris. The quadriceps femoris is responsible for extending the leg at the knee joint. If this muscle is paralyzed, the person would be unable to extend their leg at the knee joint, which aligns with the woman's complaint after slipping and falling.
39.
A knife wound penetrates the superfi cial
vein that terminates in the popliteal vein.
Bleeding occurs from which of the following
vessels?
Correct Answer
E. Lesser sapHenous vein
Explanation
The correct answer is the lesser saphenous vein. In this scenario, the superficial vein that is penetrated is the one that terminates in the popliteal vein. Among the options provided, the only vein that terminates in the popliteal vein is the lesser saphenous vein. Therefore, bleeding would occur from the lesser saphenous vein.
40.
A patient experiences paralysis of the
muscle that originates from the femur and
contributes directly to the stability of the
knee joint. Which of the following muscles is
involved?
Correct Answer
A. Vastus larealis
Explanation
The correct answer is Vastus lateralis. The question states that the muscle originates from the femur and contributes directly to the stability of the knee joint. The Vastus lateralis muscle meets both of these criteria. It originates from the femur and is one of the four muscles that make up the quadriceps muscle group, which is responsible for extending the knee joint and providing stability.
41.
42. A 24-year-old woman complains of
weakness when she extends her thigh and
rotates it laterally. Which of the following
muscles is paralyzed?
Correct Answer
D. Gluteus maximus
Explanation
The gluteus maximus is responsible for extending the thigh and rotating it laterally. If this muscle is paralyzed, it would result in weakness in these movements. Therefore, the correct answer is Gluteus maximus.
42.
A patient with hereditary blood clotting
problems presents with pain in the back of
her knee. An arteriogram reveals a blood clot
in the popliteal artery at its proximal end.
Which of the following arteries will allow
blood to reach the foot?
Correct Answer
D. Lateral circumflex femoral
Explanation
The lateral circumflex femoral artery is the correct answer because it is not affected by the blood clot in the popliteal artery. It is a branch of the deep femoral artery and supplies blood to the lateral thigh. Since it is not dependent on the popliteal artery for blood flow, it can still provide blood to the foot despite the clot. The other arteries listed, such as the anterior tibial, posterior tibial, peroneal, and superior medial genicular arteries, are all branches of the popliteal artery and would be affected by the clot, limiting blood flow to the foot.
43.
A 72-year-old woman complains of a
cramp-like pain in her thigh and leg. She
was diagnosed as having a severe intermittent
claudication. Following surgery, an
infection was found in the adductor canal,
damaging the enclosed structures. Which of
the following structures remains intact?
Correct Answer
D. Great sapHenous vein
Explanation
The great saphenous vein remains intact because the infection and damage were found in the adductor canal, which does not involve the great saphenous vein. The adductor canal is located in the thigh and contains the femoral artery, femoral vein, saphenous nerve, and nerve to the vastus medialis. However, the great saphenous vein is not enclosed within the adductor canal and therefore remains unaffected.
44.
A basketball player was hit in the thigh
by an opponent’s knee. Which of the following
arteries is likely to compress and cause
ischemia because of the bruise and damage
to the extensor muscles of the leg?
Correct Answer
C. Anterior tibial
Explanation
The anterior tibial artery is likely to compress and cause ischemia because it is located in the front of the leg and supplies blood to the extensor muscles. The bruise and damage to the extensor muscles can lead to swelling and compression of the artery, restricting blood flow and causing ischemia.
45.
A 17-year-old boy was stabbed during a
gang fi ght resulting in transection of the
obturator nerve. Which of the following
muscles is completely paralyzed?
Correct Answer
C. Adductor longus
Explanation
The obturator nerve innervates the muscles of the medial compartment of the thigh, which includes the adductor longus muscle. When the obturator nerve is transected, it leads to complete paralysis of the adductor longus muscle. Therefore, the correct answer is Adductor longus.
46.
An injury to the leg of a golfer results in
loss of the ability to invert the foot. Which
of the following muscles is most likely
paralyzed?
Correct Answer
A. Tibialis posterior
Explanation
An injury to the leg of a golfer resulting in the loss of the ability to invert the foot suggests damage to the tibialis posterior muscle. The tibialis posterior muscle is responsible for inversion of the foot, which is the movement of turning the sole of the foot inward. Paralysis of this muscle would cause the inability to perform this movement, leading to the observed symptom.
47.
Before knee surgery, a surgeon ligates
arteries participating in the anastomosis
around the knee joint. Which of the following
arteries is most likely spared?
Correct Answer
D. SapHenous branch of the descending
genicular
Explanation
The saphenous branch of the descending genicular artery is most likely spared during knee surgery. The other arteries mentioned, such as the lateral superior genicular artery, medial inferior genicular artery, descending branch of the lateral femoral circumflex artery, and anterior tibial recurrent artery, are all involved in the anastomosis around the knee joint and would therefore be ligated during surgery.