Recon Qs

Question 1

What is the pattern of medial compartment wear w/ intact and deficient ACL

Answer 1

Intact: ant med, correctable varus
Deficient: post med, fixed varus

Why get a stress valgus XR before unis

Question 2

5 minor MSIS criteria for periprosthetic infection (5)

Answer 2

Need 3 minor:

ESR >30 , CRP >10
Tap:
- Synovial WBC > 3000
- PMN > 80%
1 positive culture from joint
1 positive frozen from intra op (>5 neutro/HPF)

Question 3

2 MSIS major criteria for periprosthetic joint injection

Answer 3

2 cultures with same bug
Draining sinus tract

Question 4

Which patients is a MOM hip CI for

Answer 4

Young women - metal debris teratogenic?

Other concerns include renal failure, cardiomyopathy and carcinogenesis

*remember all hip resurfacing is MOM

Question 5

Where is the pop art in relation to PCL

Answer 5

Post + lat

Question 6

What are the complications and ways to work up after hip resurfacing

Answer 6

FNF - CT, less likely after 2yrs post op
Aseptic loosening - bone scan
Iliopsoas irritation - fem head to big, diagnostic injection
Metallosis - Co levels

Question 7

What implant is more likely to develop patellar clunk

Answer 7

PS knees bc femoral component design

Question 8

What is elevated serum Co

Answer 8

> 1ppb
Think trunnionosis

Question 9

Direct anterior plane

Answer 9

TFA (SGA n) + rectus (fem n.)

Question 10

What is the dominant BS to the femoral head
What is the artery that runs along piriformis
What vessel runs along vastus medialis and may bleed during subvastas TKA

Answer 10

Med fem circm #1
IGA along piriformis, can be a major supplier in addition
Sup med genic art

Question 11

In a lateral tibial plateau frx, what amt of residual widening of the entire plateau (relative to the distal femur) could be within normal?

Answer 11

<2mm
Bc tibial plateau width is not always the same as distal femoral width

Question 12

Describe source of pain with anterior vs posterior pain during FABER testing

Answer 12

Ant: hip joint
Post: SI joint

Post hip joint pain w/ FADIR

Question 13

AAOS knee OA guidelines:
Strong - 3
Against - 2
Inconclusive - 2

Answer 13

Strong
1. Exercise
2. NSAIDS (specifically naproxen)
3. Tramadol

Against
1. Viscosupplementation
2. Scoping for arthritis

Inconclusive: PRP, stem cells

Question 14

Describe 4 categories for femoral bone loss

Answer 14

1. Min metaph bone loss - geometry maintained, treat like a normal femur
2. Prox metaph bone loss so can’t support metaphyseal implant - diaphyseal fixation stem
3. Metaphysis gone, question now is can the diaphysis support the stem
   - Young: impaction graft w/ cement
   - Older: fluted taper or diaphyseal coated stems
4. Metaph + diaph bone loss
   - PFR / allograft prostheses (both cemented)

Question 15

How long to wait to drive after TKA to resume braking speed

Answer 15

4wks