HIGH YIELD II Flashcards
when are cannulated screws used?
when AO tech for solid screws isn’t used
for jones fx use?
tap
headless compression screws are beneficial in that they?
provide less compression, highest compression are conventional screws
the smaller the pitch, the more what?
threads engage a given depth of cortex
2 functions of screw head?
to attach a rotational drive
to arrest forward motion
no countersink means?
high mean stress
countersink means?
low mean stress
benefits of countersink?
creatures even platform near cortex
allows more uniform compression
decreases prominent hardware
over countersink: no resistance to head of screw
purpose of washers?
prevents sinking in soft bone
more uniform compression
distal tibia
no gliding hole means?
no compression
gliding hole means?
compression
conditions for inter fragmentary compression using the lag screw principle with a cortical screw?
no hold in near fragment
thread hold in far fragment
screw head to arrest screw progression
what is the insertion of a lag screw?
drill near cortex drill the far cortex counter sink measure tap insert screw into hole
near and far country meadows to screw
instruments needed?
reduction forceps surgical power tools glide hole drill bit top hat pilot hole drill bit countersink depth gauge tap w/ cover appropriately sized cortical screw and driver