Download 1. Supination of the hand and forearm would be diminished by loss

1. Supination of the hand and forearm would be diminished by loss of
radial nerve function. But one very powerful supinator would
remain intact and unaffected, namely:
Brachialis
Brachioradialis
Biceps brachii
Flexor carpi radialis
Supinator
2. A worker doing repetitive lifting develops an inflammation in the
tendon of origin of the extensor carpi radialis brevis muscle,
commonly called "tennis elbow". The focal point of pain would
most likely be near which palpable bony landmark?
Coronoid process of ulna
Lateral epicondyle of humerus
Lateral supracondylar ridge of humerus
Medial epicondyle of humerus
Medial supracondylar ridge of humerus
Olecranon
Posterior (subcutaneous) border of ulna
3. The anterior interosseous is a branch of which nerve?
Axillary
Median
Musculocutaneous
Radial
Ulnar
4. In an attempt to commit suicide by slashing the ventral side of the
wrist, the two tendons of the flexor digitorum superficialis located
most superficially were completely severed. What movement
would be affected?
Flexion of the MP and IP joints of the thumb
Flexion of the PIP joints of digits 2 and 5
Flexion of the PIP joints of digits 3 and 4
Flexion of the DIP joints of digits 2 and 5
Flexion of the DIP joints of digits 3 and 4
5. What muscle is innervated by branches of both the median and
ulnar nerves?
Flexor carpi ulnaris
Flexor digitorum profundus
Flexor digitorum superficialis
Flexor pollicis longus
Pronator quadratus
6. Interruption of the median nerve in the cubital fossa affects what
movement(s) of the thumb?
Flexion
Opposition
Both
Neither
7. Compression of the median nerve in the carpal tunnel affects
which hand muscle(s)?
Dorsal interossei
Flexor pollicis brevis
Flexor pollicis longus
Opponens digiti minimi
Palmar interossei
8. Structures within the carpal tunnel include the:
Radial bursa
Ulnar bursa
Both
Neither
9. A patient is severely limited in extension at the wrist joint after
several months in a cast following a Colles fracture. Which joint
would be especially important in therapy to regain full extension?
carpometacarpal
distal radioulnar
midcarpal
radiocarpal
ulnocarpal
10.
The victim of multiple shrapnel wounds to the upper limb
must have his forearm amputated at midlength. Because of
concomitant damage in the patient's arm, the surgeon must ligate
the main artery at some point. The best chance of saving collateral
circulation to the stump of the forearm would be when the ligature
is placed just below which of the following?
Beginning of brachial artery
Origin of the deep brachial artery
Origin of the superior ulnar collateral artery
Origin of the inferior ulnar collateral artery
Bifurcation of the brachial artery
11.
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
12.
A middle-aged woman comes to you complaining of pain on
the lateral side of her right elbow, so severe that she holds her
eating utensils in her left hand to eat. She says that she spent the
weekend putting in a new garden plot and that it involved
loosening and turning over a large area of grass sods with a
garden fork. You find that the region just proximal to the lateral
epicondyle of her humerus is painful to the touch. There is no
sensory loss in her forearm or hand. You suspect a localized
tearing of the origin of a muscle producing the equivalent of "tennis
elbow." The muscle most likely involved is the:
brachioradialis
common flexor tendon
extensor carpi radialis brevis
extensor digitorum
pronator teres
13.
A boy fell onto a sharp object and cut his deep radial nerve
as it emerged from the supinator muscle. The artery joining it at
this point was also injured. The injured artery is the:
anterior interosseous
common interosseous
posterior interosseous
radial
ulnar
14.
While going up for a rebound, a basketball player jams her
middle finger against the ball. She experiences severe pain and
the trainer notes that she can no longer extend the distal phalanx
of the finger. The injury has avulsed (torn away from the bone)
which structure from her distal phalanx to produce this condition?
extensor carpi radialis brevis tendon
extensor carpi radialis longus tendon
extensor digiti minimi tendon
extensor expansion
extensor indicis tendon
15.
The tendons on the dorsal side of the wrist are held in place
by a thickening of the antebrachial fascia called the:
bicipital aponeurosis
extensor expansion
extensor retinaculum
interosseous membrane
16.
palmar carpal ligament
The function of the posterior interosseous nerve is:
motor to the brachioradialis
motor to the extensor carpi ulnaris
parasympathetic to the dorsum of the forearm
sensory from the wrist joint
sensory from the dorsum of the forearm
17.
Development of "tennis elbow" (lateral epicondylitis) involves
the origin of which muscle?
Abductor pollicis longus
Anconeus
Brachioradialis
Extensor carpi radialis brevis
Triceps brachii
18.
In an industrial accident, the artery passing lateral to the
pisiform bone is cut. This artery is the
Deep palmar arch
Radial
Superficial palmar arch
Superficial palmar branch of the radial artery
Ulnar
19.
After suffering a gunshot wound to the forearm, it was
determined that the posterior interosseous nerve was severed.
What function was lost?
Sensory from the wrist joint
Motor to brachioradialis
Motor to the extensor carpi radialis longus
Parasympathetic to the dorsum of the forearm
Motor to the flexor digitorum superficialis
20.
When falling on an outstretched hand, the most commonly
dislocated carpal bone is the
Scaphoid
Trapezoid
Lunate
Capitate
Hamate
21.
If the musculocutaneous nerve is severed at its origin from
the brachial plexus, flexion at the elbow is greatly weakened but
not abolished. What muscle remains operative and can contribute
to flexion?
Brachialis
Brachioradialis
Coracobrachialis
Long head of biceps brachii
Short head of biceps brachii
22.
After falling on the ice, it was determined that a patient had a
Colles' fracture. Care must be taken to relieve tension on the
broken distal end of the radius created by the pull of which
muscle?
Extensor carpi ulnaris
Brachioradialis
Extensor carpi radialis longus
Pronator quadratus
Extensor carpi radialis brevis
23.
If the tendon of palmaris longus were transected, what
movement would be affected?
Flexion of the MP and IP joints of the thumb
Flexion of the proximal IP joints of digits 2 and 5
Flexion of the proximal IP joints of digits 3 and 4
Flexion of the wrist
Extension of the wrist
24.
What muscle is supplied by both the median and ulnar
nerves?
Flexor carpi ulnaris
Flexor digitorum profundus
Flexor digitorum superficialis
Flexor pollicis longus
Pronator quadratus
25.
The pulse of the radial artery at the wrist is felt immediately
lateral to which tendon?
Abductor pollicis longus
Extensor pollicis longus
Flexor carpi radialis
Flexor digitorum profundus
Palmaris longus
26.
If the medial epicondyle of the humerus is fractured and the
nerve passing dorsal to it is injured, which muscle would be most
affected?
Extensor carpi ulnaris
Extensor digitorum
Flexor carpi ulnaris
Flexor digitorum profundus
Flexor digitorum superficialis
1. The correct answer is:
biceps brachii
Biceps brachii supinates the arm, but it is not innervated by the radial
nerve--instead, it is innervated by the musculocutaneous nerve. So, it
would not be affected by a radial nerve injury. Brachialis is also
innervated by the musculocutaneous nerve, but it is only involved with
flexing the forearm--it is not a supinator. Brachioradialis flexes the elbow
and assists in pronation and supination--it is innervated by the radial
nerve and would be paralyzed after a radial nerve injury. Flexor carpi
radialis is a flexor, not a supinator--it is innervated by the median nerve.
Finally, supinator is innervated by the deep radial nerve.
2. The correct answer is:
lateral epicondyle of the humerus
The extensor carpi radialis brevis muscle originates from the common
extensor tendon off the lateral epicondyle of the humerus. So, an injury
to this tendon would result in pain near the lateral epicondyle. Tennis
elbow is due to the repetitive use of superficial extensor muscles of the
forearm--the pain is often felt at the lateral epicondyle and it radiates
down the posterior surface of the forearm. None of the other bony
landmarks are associated with the common extensor tendon, although
the medial epicondyle is the origin of the common flexor tendon.
3. The correct answer is:
median
The anterior interosseous nerve is a branch of the median nerve that
provides motor innervation to the deep muscles in the flexor
compartment, including flexor pollicis longus, the radial half of flexor
digitorum profundus, and pronator quadratus. The other related nerve to
think about is the posterior interosseous nerve, which is the terminal
branch of the deep radial nerve. It provides sensory innervation to the
wrist area.
4. The correct answer is:
flexion of the PIP joints of digits 3 and 4
When cutting the ventral side of the wrist, the first tendons cut would be
the tendons of flexor digitorum superficialis. These tendons help flex the
metacarpophalangeal and proximal interphalangeal joints, but not the
distal interphalangeal joints. Flexor digitorum profundus (which has
deeper tendons) is responsible for flexing the distal interphalangeal
joints. To understand the next part of the question, look at Netter plate
443. The tendons of flexor digitorum superficialis are arranged in a
packet with two superficial tendons and two deeper tendons. The
tendons that go to fingers 3 and 4 are superficial, while the ones to
finger 2 and 5 are underneath. So, the tendons to fingers 3 and 4 will be
cut, impairing flexion of the proximal interphalangeal joints of digits 3 and
4.
5. The correct answer is:
Flexor digitorum profundus
The median and ulnar nerve both innervate flexor digitorum profundus.
Flexor carpi ulnaris is innervated by the ulnar nerve only. Flexor
digitorum superficialis and flexor pollicis longus are innervated by the
median nerve. Pronator quadratus is innervated by the anterior
interosseus nerve, which is a branch of the median nerve.
6. The correct answer is:
Both
The recurrent branch of the median nerve innervates the thenar
compartment of the hand. This nerve innervates opponens pollicis,
which opposes the thumb, and flexor pollicis brevis, which helps to flex
the thumb. So, disrupting the median nerve would impair both flexion
and opposition of the thumb.
7. The correct answer is:
Flexor pollicis brevis
The recurrent branch of the median nerve innervates the thenar
compartment of the hand, including flexor pollicis brevis, abductor
pollicis brevis, and opponens pollicis. So, if the median nerve was
compressed, all of these muscles might be affected. The dorsal
interossei, palmar interossei, and opponens digiti minimi are all muscles
of the hand which are innervated by the deep branch of the ulnar nerve.
Flexor pollicis longus is innervated by the median nerve, but it is a
forearm muscle which is proximal to the carpal tunnel. Therefore, it
would not be affected by compressing the median nerve in the carpal
tunnel.
8. The correct answer is:
Both
The radial bursa and ulnar bursa are both found in the carpal tunnel.
These bursae are complex synovial coverings that protect the flexor
tendons. The carpal tunnel is formed where the flexor retinaculum spans
from the scaphoid and trapezium to the hamate and pisiform, deep and
slightly distal to the palmar carpal ligament. This creates a canal that
covers the flexor digitorum superficialis tendons, the flexor digitorum
profundus tendons, the tendon of flexor pollicis longus, and the median
nerve. These tendons in the carpal tunnel are covered by the ulnar and
radial bursae. The flexor digitorum superficialis and flexor digitorum
profundus tendons are covered by the ulnar bursa, and the tendon of
flexor pollicis longus is covered by the radial bursa. So, both bursae are
in the carpal tunnel.
9. The correct answer is:
radiocarpal
The radiocarpal joint is the joint commonly known as the wrist joint--it is
a condyloid (oval) type of synovial joint that allows for flexion and
extension, abduction and adduction, and circumduction. A Colles
fracture is a fracture of the distal end of the radius--this is why this sort of
break would limit movement between the radius and carpals. The
carpometacarpal joint is found between the distal row of carpals and the
metacarpals--these joints are mobile for the thumb and little finger,
allowing extension, flexion, abduction, and adduction. However, the
carpometacarpal joints are quite immobile for the middle three fingers.
The distal radioulnar joint is located between the distal ends of the
radius and ulna--this joint allows the radius and ulna to rotate around
each other during pronation and supination. The midcarpal joint is
located between the proximal and distal row of carpals--this joint is
important for flexion and extension of the hand. As for the "ulnocarpal
joint," the ulna does not articulate with the carpal bones--it articulates
with the distal end of the radius only.
10. The correct answer is:
bifurcation of the brachial artery
The brachial artery bifurcates near the elbow. It forms two branches that
become the radial and ulnar arteries. If these arteries were ligated after
this bifurcation, there would be a chance at saving collateral circulation
to the forearm because the ulnar artery might have already given off its
common interosseous branch, which could carry blood to the forearm
through the anterior and posterior interosseus arteries. Ligating near the
beginning of the brachial artery would stop blood from flowing through
the rest of the upper limb. Ligating near the origin of the deep artery, by
the origin of the superior ulnar collateral artery, or near the origin of the
inferior ulnar collateral artery might preserve enough collateral
circulation to supply the elbow. However, there would not be collateral
circulation to the forearm. For a better picture of these arterial
connections, see Netter Plate 434.
11. The correct answer is:
median nerve
The median nerve provides sensory innervation to the skin of the radial
3.5 fingers of the palm. So, the patient's loss of cutaneous sensation is
suggestive of a median nerve injury. The location of the injury also
implies that there has been an injury to the median nerve--this nerve
enters the hand by crossing under the flexor retinaculum on the anterior
side of the wrist.
The lateral and medial antebrachial cutaneous nerves provide
cutaneous innervation to the anterior side of the forearm--the symptoms
here are not consistent with an injury to these nerves. The radial nerve
innervates the radial side of the dorsum of the hand but does not
innervate the palmar side of the hand. The ulnar nerve innervates the
medial (ulnar) side of both the dorsum and palm of the hand
12. The correct answer is:
brachioradialis
Tennis elbow is usually caused by inflammation of the common extensor
tendon on the lateral side of the forearm, but we know that that's not
what happened here. Instead, the patient tore a muscle at its origin, near
the lateral epicondyle of the humerus. Brachioradialis originates from the
upper two-thirds of the lateral supracondylar ridge of the humerus, so
this is the muscle that she probably tore. This also makes sense given
her activities--brachioradialis flexes the elbow and assists in pronation
and supination, so she would have been using this muscle while
gardening.
The common flexor tendon is associated with the medial epicondyle, not
the lateral epicondyle. Extensor carpi radialis brevis and extensor
digitorum take origin from the common extensor tendon, which attaches
to the lateral epicondyle. This tendon would be inflamed in a classic
case of tennis elbow, but the common extensor tendon is not the
structure that was injured in this patient's case. Pronator teres takes
origin from the common flexor tendon and the medial side of the ulna.
13. The correct answer is:
posterior interosseous
The deep radial nerve emerges from the supinator muscle and runs in
the deep layer of the posterior forearm. It runs next to the posterior
interosseous artery, which, along with the anterior interosseous artery, is
a branch of the common interosseous artery. The common interosseous
artery comes off the ulnar artery to give these two branches that supply
the deep arm on the anterior and posterior sides. The ulnar and radial
arteries are branches of the brachial artery that run down the ulnar and
radial sides of the anterior arm.
14. The correct answer is:
extensor expansions
The extensor expansions are the expanded distal ends of the extensor
tendons which wrap around the heads of the metacarpals and the bases
of the proximal phalanges and insert on the bases of the middle and
distal phalanges. These extensor expansions hold the extensor tendon
in the middle of the digit and provide a place for the lumbricals and
interossei to attach. If an extensor expansion was torn, the extensor
tendon would not be held in place and a lumbrical would be torn from its
attachment. This would impair extension at the joint.
Extensor carpi radialis brevis and longus are involved with extending the
wrist and abducting the hand. These muscles do not produce extension
at the fingers. Extensor digiti minimi and extensor indicis help with
extension at the 5th and 2nd finger, but they do not act at the third
finger.
15. The correct answer is:
extensor retinaculum
The extensor compartment is on the dorsal surface of the arm. The
tendons of the muscles from this compartment pass onto the dorsal side
of the wrist by crossing under the extensor retinaculum. The bicipital
aponeurosis is the membranous band that runs from the biceps tendon
across the cubital fossa and merges with the antebrachial fascia over
the forearm flexor muscles. An extensor expansion wraps around the
head of a metacarpal and the base of the proximal phalanx to hold the
extensor tendon in place on the digit. The interosseous membrane
connects the radius to the ulna, and the palmar carpal ligament is a
thickening of the antebrachial fascia over the palmar surface of the wrist.
The palmaris longus and ulnar neurovascular bundle pass deep to the
palmar carpal ligament, and the flexor retinaculum lies deeper and more
distal, forming the carpal tunnel.
16. The correct answer is:
sensory to the wrist joint
The posterior interosseous nerve is the sensory continuation of the deep
radial nerve, distal to its motor branches to the extensor muscles (this is
at odds with how the posterior interosseous nerve is considered
clinically, that is, it is considered synonymous with the deep radial) . It
reaches the wrist joint and carpal bones for proprioceptive sense from
these structures. Brachioradialis is innervated by the radial nerve, and
extensor carpi ulnaris is innervated by the deep radial nerve. There are
no parasympathetic nerves in the forearm, and sensory innervation from
the dorsum of the forearm is carried by the radial nerve.
17. The correct answer is:
extensor carpi radialis brevis
"Tennis elbow" is due to repetitive use of the superficial extensor
muscles of the forearm. The pain is felt on the lateral epicondyle and
radiates down the posterior surface of the forearm. With tennis elbow,
the repeated flexion and extension of the wrist strains the attachment of
the common extensor tendon, producing inflammation of the periosteum
of the lateral epicondyle and the common extensor attachment of the
muscles. The only muscle listed which takes origin from the common
extensor tendon is the extensor carpi radialis brevis. So, that is the
correct answer. (Extensor carpi ulnaris also takes origin from the
common extensor tendon, so it might be responsible for some of the
symptoms too.)
None of the other muscles take origin from the common extensor
tendon. Abductor pollicis longus originates from the middle one-third of
the posterior surface of the radius, the interosseous membrane, and the
mid-portion of posterolateral ulna. Anconeus originates from the lateral
epicondyle of the humerus. Brachioradialis originates from the upper
two-thirds of the lateral supracondylar ridge of the humerus--it is not a
muscle from the common extensor tendon. Finally, triceps brachii is not
really assoiciated with the lateral epicondyle or the common extensor
tendon--this muscle attaches to the olecranon process of the ulna.
18. The correct answer is:
Ulnar artery
The ulnar artery runs on the medial side of the wrist, near pisiform and
hamate. It supplies most of the blood to the superficial palmar arterial
arch in the hand, but gives a deep ulnar branch to complete the deep
palmar arch in the hand. The radial artery runs on the lateral side of the
wrist, near scaphoid and trapezium. It supplies most of the blood to the
deep palmar arterial arch, but gives off a superficial palmar branch of the
radial artery which completes the superficial palmar arch in the hand.
The superficial and deep palmar arches are found more distal in the
hand, near the heads and bases of the metacarpal bones, respectively.
19. The correct answer is:
Sensory to the wrist joint
The posterior interosseous nerve is the sensory continuation of the deep
radial nerve, distal to its motor branches for the extensor muscles. It
reaches the wrist joint and carpal bones for proprioceptive sense from
these structures. Brachioradialis and extensor carpi radialis longus are
innervated by the radial nerve, and extensor carpi radialis brevis is
innervated by the deep radial nerve. Flexor digitorum superficialis is
innervated by the median nerve. There are no parasympathetic nerves
in the limbs or body wall.
20. The correct answer is:
Lunate
It is fairly common for the lunate to be dislocated anteriorly--this injury
may result from a fall on an extended wrist. The lunate may be pushed
out of its place on the floor of the carpal tunnel and move toward the
palm of the wrist. This dislocation may compress the median nerve and
lead to carpal tunnel syndrome. Also remember: scaphoid, the lateral
bone in the proximal row of carpals, is frequently fractured when
someone falls on an outstretched wrist! Capitate, hamate, and trapezoid
are not commonly injured in these falls.
21. The correct answer is:
brachioradialis
The Colles' fracture is a fracture to the distal end of the radius. It usually
occurs when someone tries to catch themselves from falling on an
outstretched arm. So, you need to look in the answer choices for a
muscle that inserts on the distal end of the radius. Brachioradialis inserts
on the lateral side of the base of the styloid process of the radius, so this
muscle could pull the broken piece of the radius out of place. This is why
a cast over a Colles' fracture needs to extend up to the elbow-brachioradialis needs to be immobilized!
Extensor carpi ulnaris inserts on the medial side of the base of the 5th
metacarpal. Extensor carpi radialis longus inserts on the dorsum of the
second metacarpal bone. Pronator quadratus extends between the distal
ulna and radius-- it serves to pronate the hand. Although this muscle
attaches to the broken part of the radius, it is not the most important
muscle to stabilize following the injury. Extensor carpi radialis brevis
inserts on the dorsum of the third metacarpal bone. So, none of the
other muscles would pull on the distal piece of the radius as much as
brachioradialis.
22. The correct answer is:
brachioradialis
The Colles' fracture is a fracture to the distal end of the radius. It usually
occurs when someone tries to catch themselves from falling on an
outstretched arm. So, you need to look in the answer choices for a
muscle that inserts on the distal end of the radius. Brachioradialis inserts
on the lateral side of the base of the styloid process of the radius, so this
muscle could pull the broken piece of the radius out of place. This is why
a cast over a Colles' fracture needs to extend up to the elbow-brachioradialis needs to be immobilized!
Extensor carpi ulnaris inserts on the medial side of the base of the 5th
metacarpal. Extensor carpi radialis longus inserts on the dorsum of the
second metacarpal bone. Pronator quadratus extends between the distal
ulna and radius-- it serves to pronate the hand. Although this muscle
attaches to the broken part of the radius, it is not the most important
muscle to stabilize following the injury. Extensor carpi radialis brevis
inserts on the dorsum of the third metacarpal bone. So, none of the
other muscles would pull on the distal piece of the radius as much as
brachioradialis.
23. The correct answer is:
Flexion of the wrist
Palmaris longus is a small muscle in the anterior compartment of the
arm--it flexes the hand at the wrist and tightens the palmar aponeurosis.
If this tendon was cut, it would be more difficult to flex the wrist. Flexor
pollicis longus flexes the MP and IP joints of the thumb. Flexor digitorum
profundus and superficialis flex the proximal IP joints of digits 2, 3, 4,
and 5. Extensor carpi ulnaris, extensor carpi radialis longus and
extensor carpi radialis brevis all extend the wrist.
24. The correct answer is:
Flexor digitorum profundus
The radial half of flexor digitorum profundus is supplied by the median
nerve, while the ulnar half of flexor digitorum profundus is supplied by
the ulnar nerve. The ulnar nerve also supplies flexor carpi ulnaris in the
anterior forearm. (Remember--the ulnar nerve is the 1 1/2 nerve--it
supplies 1 1/2 muscles in the anterior forearm, and it supplies cutaneous
innervation to 1 1/2 fingers on the ulnar side of the hand!)
Flexor digitorum superficialis, flexor pollicis longus, and pronator
quadratus are innervated by the median nerve.
25. The correct answer is:
Flexor carpi radialis
The radial artery runs on the radial side of the wrist, lateral to the tendon
of flexor carpi radialis. So, the radial pulse will be felt immediately lateral
to this tendon. Remember--the radial artery enters the wrist on the
anterior side. This means that the extensor tendons, which are on the
posterior side of the wrist, will not be involved with the radial artery! The
tendons for flexor digitorum profundus and superficialis are found more
towards the center of the wrist, not on the wrist's lateral side. These
tendons cross under the flexor retinaculum to reach the hand.
26. The correct answer is:
Flexor carpi ulnaris
The nerve passing dorsal to the medial epicondyle of the humerus is the
ulnar nerve. In the forearm, the ulnar nerve innervates flexor carpi
ulnaris and the ulnar side of flexor digitorum profundus. So, flexor carpi
ulnaris would be most affected if the ulnar nerve was disrupted. What
other symptoms might you see? Paralysis of hand muscles (except for
the thenar compartment and the first two lumbricals) and numbness over
the ulnar 1.5 digits in the hand!
The extensor muscles (extensor digitorum and extensor carpi ulnaris)
are in the posterior compartment of the forearm--they are innervated by
the radial nerve. Flexor digitorum superficialis is innervated by the
median nerve only. Although the ulnar side of flexor digitorum profundus
would be impaired following the injury, the radial side of flexor digitorum
profundus would still be innervated by the median nerve.
.