JOints Flashcards
What artery is at risk with lateral retinacular release?
Lateral superior genicular artery
(last one left after medial arthrotomy and fat pad remoal –> increased risk of AVN to patella if cut).
Largest arterial contribution to the patella is…
from inferomedial. (disrupted w/ arthrotomy/fat pad removal)
Treatment of patella fracture w/ minimal lag, stable implant
cast/brace and don’t need therapy
Treatment of patella fx w/ loose implant
adequate bone (12-13 mm): revise
inadequate bone: patellectomy/suture bone to tissue/imbrication (can come back for extensor recon later)
Late manipulation under anesthesia has high risk of…
fracture (esp supracondylar femur fracture).
What is the most important factor for patellar clunk syndrome?
Femoral implant design
- wide femoral box (a small patella will settle into a large box)
- tall femoral box (increases chance that the scar will pass into the capture zone of the box)
Patellar clunk rate is low when the intercondylar box height is…
< 70%.
Other risk factors for patellar clunk
- small patella
- low patella
- patella baja
- increased posterior condylar offset
- previous surgery
Risk factors for anterior post wear (PS knee)
- knee hyperextension and femoral component flexion (most common)
- excess posterior tibial slope
- anterior translation of tibial component
Absolute indications for PS implant over CR
- patellectomy
- inflammatory disease
- trauma w/ PCL rupture
Disadvantages of ultracongruent knees
- increased poly surface area means more wear
- minimal rollback
Persister cells enter…
G0 phase dormancy when stressed. (abx levels above MIC).
In a biofilm, bacteria can resume…
wild type growth 2/2 removal of stress agents.
Volumetric wear =
3.14 x r(squared) x w
where r = radius of head and w = linear wear
Aspirin MOA
COX inhibitor
