OITE Lecture

Question 1

Periprosthetic WBC/diff for acute infx

Answer 1

WBC > 10K

Diff > 90% polys

Question 2

Periprosthetic WBC/diff for chronic infx

Answer 2

WBC > 2K

Diff > 60% polys

Question 3

How to treat a periprosthetic infx

Answer 3

2 stage revision - explant, debridement with cx, abx spacer

6 wks IV abx

Question 4

IF you have a metal on metal implant, why don’t you want a auto differential for your aspirate

Answer 4

Auto diff can’t differentiate between lymphocytes and metal debris

Question 5

What is a treatment option for acute (<3 wk infx) periprosthetic infx

Answer 5

If no MRSA, I&D spacer exchange

Question 6

Intra-op femur fracture THA trt

Answer 6

Take the implant out
Wire
Put the implant back in

Question 7

Vancouver classification for THA periprosthetic frx

Answer 7

A - trochanteric
B - within the stem 
B1 - stem solid
B2 - stem loose, good bone stock
B3 - stem loose, bad bone stock
C - distal to stem

Question 8

How to fix vancouver Bs

Answer 8

B1 - ORIF w/ locking plates vs cerclage wires
B2 - revise
- Long cementless porous stem (gets fixation distally)
B3 - revise
- Young: allograft
- Old: DFR