Boards Facts

Question 1

What is a negative consequence of crosslinking polyethylene?

Answer 1

reduction in toughness that makes more susceptible to crack initiation and propagation

Question 2

Tricalcium phosphate vs Hydroxyapatite

Answer 2

TCP: resorbed more rapidly (larger pore size), less compressive strength, partially converts to hydroxyapatite. Resorbed by the foreign body giant cell (NOT the osteoclast)

Question 3

Stripe wear on a ceramic head indicates:

Answer 3

femoral head damage because of lift-off separation of the femoral head during gait

Question 4

early queiscent osteopenia after application of a plate is due to

Answer 4

plate-bone contact

Question 5

working length of a cotex screw is defined by:

Answer 5

diameter of the bone traversed by the screw

Question 6

highest risk of crevice corrosion caused by:

Answer 6

combining CoCr and stainless steel implants together

Question 7

buckethandle lateral meniscus with 3mm rim: fix or excise

Answer 7

reduce and fix

Question 8

natural history of saphenous nerve injury after inside out meniscus repair

Answer 8

all resolve by 4 months

- one patietn in a series had a non-absorable suture tied around it which had to be surgically explored and released

Question 9

Management of Vitamin D supplements perioperatively?

Answer 9

for ricketts, d/c vitamin D 3 weeks preop to prevent hypercalcemia

Question 10

urinary findings in Morquio syndrome

Answer 10

increased urinary keratin sulfate

Question 11

urinary findings in Hurler syndrome

Answer 11

increased urinary heparin sulfate

Question 12

lab findings of idiopathic osteoporosis:

Answer 12

normal serum calcium, phosphate, and alk phos

Question 13

breast feeding effects on bone density?

Answer 13

breast feeding mothers have 10% decreased bone mass

- give 2000mg calcium daily

Question 14

Lab findings of nutritional ricketts:

Answer 14

• low Ca
• low Phos
• Low 25-d and 1,25D
• High Alk Phos

Question 15

Type II Collegen Diseases

Answer 15

• SED
• MED
• Kniest

Question 16

genetic basis of Paget’s Disease

Answer 16

virus like inclusion bodies

• thought Paramyxovirus
• Thought Chromosome 18

Question 17

Genetic Basis of Pseudoachondroplasia

Answer 17

• COMP mutation

Question 18

Genetic Basis of Fibrous Dysplasia of Bone

Answer 18

Activating Mutation of the G protein inappropriately stimulating cAMP activity
- increases C-fos proto-oncogene

Question 19

MSK Manifestations of Ehlers Danlos

Answer 19

• Congenital hip dislocation
• Clubfoot
• Scoliosis

Question 20

Diseases caused by FGFR-3 mutations:

Answer 20

• Achondroplasia
• Hypochondroplasia
• Thanatophoric Dysplasia

Question 21

Genetic Basis of Friedrich’s Ataxia

Answer 21

Spinocerebellar ataxia
Autosomal recessive
X25 gene coding for Frataxin

Question 22

These antibiotics can penetrate macrophages and destroy intracellular Staphylococcus:

Answer 22

• clindamycin
• fluoroquinolones
• Rifampin

Question 23

Aminoglycoside Mechanism of action:

Answer 23

inhibition of 30S Ribosomal subunit to inhibit protein synthesis

Question 24

Cephalosporin Mechanism of Action:

Answer 24

Inhibition of cell wall synteshsis

Question 25

Fluoroquinolone Mechaisms of Action:

Answer 25

inhibition of DNA Gyrase

Question 26

most likely outcome of peds patients with ACL tears treated non-op

Answer 26

recurrent instability with resultant meniscal tearing