Back & Limbs Board Review Cases
1. Let's play "Where Does It Drain!" Your patient comes
to you with lesions on various areas of skin and superficial fascia.
In each case, decide to which group of lymph nodes the lesion
will drain. Abdomen, superior to umbilicus; back; scrotum; buttocks;
anal canal inferior to pectinate line
2. After recuperating from a gunshot wound to the
buttocks resulting from a hunting accident, your patient exhibits
a positive Trendelenburg's sign. Explain.
3. An elderly woman falls and breaks her hip. After
reviewing the films, the surgeon opts for ORIF and inserts an
IM nail through the femoral neck and into the femoral head. Although
the operation is a success, the surgeon worries that he may still
have to go back and do a hemiarthoplasty. Why?
4. You've been given the task of inserting the catheter
for a patient scheduled for angioplasty. What anatomical landmarks
are you looking for?
5. A defensive back making his cut to stay with
the receiver gets clipped. He experiences knee pain and limps
off the field. Upon examination in the locker room he is found
to exhibit a positive anterior drawer sign. An MRI is ordered.
What might have happened to the football player's knee?
6. A student crossing JPA to catch the bus gets
hit by a car just distal to the knee. Although no bones are broken,
the student subsequently exhibits "dropfoot." What structure
in the leg was likely damaged?
7. A leadoff batter tries to beat out a slow roller
to short. Just before he hits the bag he feels a sharp pain and
he instinctively grabs the back of his thigh. He limps back to
the dugout having been thrown out on yet another bad call by the
umpire. What probably happened to the batter?
8. Your patient complains of leg pain while walking. You suspect
his popliteal artery is at least partially blocked. You decide
to take his pulse at the ankle. Where do you place your fingers?
9. You have to do a lumbar puncture. What landmarks
do you use to insert the needle? What layers of tissue will the
needle pass through to reach CSF?
10. A middle-aged, overweight couch potato feels
a sharp pain when he bends over to pick up his 24-can case of
Bud. Subsequently he feels low back pain and pain down the posterolateral
side of his leg. What most likely happened?
11. A baby is born with spina bifida. Explain what
happened or didn't happen developmentally? How might this defect
have been prevented?
12. The patient comes to the emergency room in severe
shock. The attending tells you to start the IV.
Which vein would you use at the elbow? forearm? leg?
13. Your patient who has recently had a mastectomy
now exhibits "winged scapula." What's the most likely
reason?
14. A football player falls heavily to the ground
and feels something in his shoulder snap. He runs off the field
supporting his medially rotated upper limb. There a big knot in
the root of his neck. What happened?
15. You examine a young man who was thrown from
his motorcycle. You diagnose Erb-Duchenne paralysis. What is the
position of the upper limb and why?
16. You have to tie off the axillary artery to achieve
a bloodless field in order to repair damage to the shoulder resulting
from a gun shot wound. You ligate the axillary artery confident
that the upper limb will continue to receive adequate arterial
blood. What anatomical knowledge do you have that accounts for
your confidence?
17. Sgt. Snorkle falls off a cliff and brakes his
fall by grasping a convenient snag with his right hand. Pvt. Beetle
Bailey eventually pulls him to safety and he is rushed to an aid
station where you are fullfilling the terms of your military medical
scholarship. Upon examination you find that Sgt Snorkle is holding
his hand in a peculiar way and has lost sensation on the medial
side of his arm and to a lesser extent on the medial forearm,
hand and two ulnar fingers. What nerve (s) has been damaged and
what is the position of Sgt. Snorkle's hand?
18. Your patient works for Wampler-Longacre Foods
over in the Valley near Harrisonburg and for eight hours a day
with few breaks, she cuts the wings off of chickens as they move
down a conveyer belt. She is complaining of severe "pins
and needles" in her cutting hand. She experiences difficulty
in buttoning up her clothes when dressing. What anatomical structure
was affected in this patient?
19. A patient involved in an MVA fractures his arm
and subsequently experiences wristdrop. What happened?
20. A young boy fell from his bike on to the hard
pavement. He feels pain and tenderness at the base of the thumb.
You order a radiograph and use it to make the diagnosis. What
happened.?
21. Your patient receives what appears to be a minor
cut on the palm of his hand near the base of the thumb. Upon examination
you discover that certain of his thumb movements are impaired.
Which ones and why?
22. A recently retired man goes fly fishing every
day. He notices that his shoulder hurts every time he casts. The
pain gets so bad he comes to see you, his primary-care physician.
What do you suspect is wrong with this man's shoulder?
Back & Limbs Board Review Answers
1. Lymph from the skin and superficial fascia of the trunk and
limbs initially drains to either axillary or superficial inguinal
lymph nodes. The back, chest and abdomen superior to the umbilicus
drain to axillary nodes. Abdominal skin inferior the umbilicus,
scrotum, buttocks, and anal canal inferior to the pectinate line
drain first to superficial inguinal lymph nodes, then through
the saphenous opening to deep inguinal nodes.
2. When gluteus minimus and medius are paralyzed
due to injury to the superior gluteal nerve, the loss of isometric
contraction of those muscles causes the pelvis to dip contralaterally
when the contralateral limb is unsupported as in swing phase of
the gait..
3. Fractures of the femoral neck often result in
avascular necrosis of the femoral head and required replacement
of the head with a prothesis.
4. Just inferior to the midinguinal point (midway
between the ASIS and pubic tubercle) the femoral artery passes
anterior to the femoral head.
5. Classic case of the “unhappy triad”
consisting of a torn ACL, medial collateral ligament and medial
meniscus.
6. Common fibular (peroneal) nerve.
7. Hamstring pull (strain).
8. There are two places to take a pulse at the ankle:
1) at the posterior tibial artery just posterior to the medial
malleolus , 2) at the dorsalis pedis artery just distal to the
ankle joint between the tendons of extensor hallucis and extensor
digitorum longus.
9. The supracristal line, i.e., a line connecting
the highest points on the iliac crest, passes through the spinous
process of L4. The needle should pass either immediately superior
or inferior to the L4 spinous process.
10. Herniated nucleus pulposus impinging on nerve
root of L5 or S1 spinal nerve.
11. The vertebral lamina failed to fuse in the midline.
Women of childbearing age can ingest folic acid supplements to
prevent this defect.
12. Superficial veins are commonly used for intravenous
infusions. At the elbow the median cubital vein is used.. In the
distal forearm, the cephalic vein can be accessed just posterior
to the radial styloid, and in the distal leg, the great saphenous
vein can be cannulated just anterior to the medial malleolus.
13. The long thoracic nerve was injured during surgery.
14. The clavicle is the most commonly fractured
bone in the body. The arm is held close to the body and medially
rotated due to action of powerful adductors and medial rotators
like pectoralis major. It must be supported due to the weight
of the limb. The medial end of the fractured clavicle is elevated
by sternocleidomastoid.
15. This is an upper brachial plexus injury involving
C5 and C6 nerve roots and thus profoundly affecting the suprascapular,
musculocutaneous and axillary nerves. The arm is adducted and
medially rotated. The forearm is extended and pronated.
16. This is a classic example of collateral circulation
so prevalent throughout much of the body. The axillary artery
is ligated distal to the thyrocervical trunk and proximal to the
subscapular artery. Blood passing into the posterior shoulder
via the suprascapular and transverse cervical arteries can then
course in a retrograde fashion through the circumflex scapular
and then subscapular artery to reach the brachial and vascularize
the upper extremity.
17. Sgt. Snorkle has experienced a lower brachial
plexus injury also known as Klumpke palsy. It results in damage
to the T1 and C8 nerve roots. Lower trunk nerves are non-functional.
They are medial brachial and antebrachial cutaneous nerves, ulnar
nerve and the part of the median nerve that supplies innervation
to the hand. Thus Sgt. Snorkle exhibits a claw hand, hyperextended
at the MP joints and flexed at the IP joints. His thumb would
be flattened and abducted.
18. Tendosynovitis of the common flexor sheath (ulnar
bursa) has compressed the median nerve against the flexor retinaculum
resulting in the symptoms described in this problem. Damage to
the median nerve affects the thenar muscles that are necessary
to oppose the thumb as in buttoning a shirt.
19. The fractured humerus damaged the radial nerve
as it coursed in the radial groove. The radial nerve innervates
the muscles that extend the wrist.
20. The boy has fractured his scaphoid , a bone
particularly susceptible to avascular necrosis.
21. The recurrent branch of the median nerve has
been severed. Most noticeably, opposition of the thumb would be
lost. To a lesser extent thumb flexion and abduction would be
affected.
22. You suspect that repeated casting has caused
a rotator cuff tear. Most frequently the tendon of supraspinatus
is torn.
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