Anterior trim line: where must it go?
- at least halfway up the patella
- regardless of suspension type
Why does the anterior trim line need to go halfway up the patella?
- must be high enough to provide counterpressure
- low enough to not pinch
Lateral trimline
not as important as anterior and posterior
function of posterior trimline
- gives counterpressure so that pressure can be distributed appropriately to anterior side
- holds knee over patellar indentation
Problem with a low trimline
socket could fall off
Problem with a high trimline
pinches during sitting
How much flexion will you give a TT pt
90˚
not more
Flexion moment and stability
- decreases stability
- doesn’t necessarily cause buckling
What will help with a flexion moment?
quad strength
Why don’t you want to continue having a flexion moment at the knee?
- increased energy expenditure over time
- requires quad contraction to resist
- increased pressure on anterior bony surfaces
distal anterior tibia aka
kick point
What does an extension moment at the knee increase?
stability
An extension moment increases stability but sacrifices
mobility
How does the body compensate for an extension moment at the knee?
- may use hamstrings to advance limb
- high energy cost
How much pistoning is acceptable?
up to 1/4 inch
How would you check pistoning?
- draw line on sock in WB
- have them shift weight off of it and draw another line
- measure
What should you do if you see pistoning?
Add a ply and see if it helps
What should you do with ply if the leg length is too high?
decrease by 1 ply to see if it fits better
ply throughout the day
- may have to adjust
- can fluctuate and get bigger or smaller
- add/subtract ply
Why will moisture wicking not be a huge concern after a while?
sweat glands stop working over time
Gait training with TT
fairly uninvolved
