אפקה - המכללה האקדמית להנדסה בתל אביב | תערוכת פרויקטים בהנדסה 2015 - קטלוג פרויקטים

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2014 --- 2
4.1. Numerical Model
Stress distribution in the stump within BS
Different force angle in the BS model
The increased forced applied by the 45 [deg]
angle (walking), causes greater stress than the
vertical normal forces applied when standing.
Different distance between the truncated bone
and the bottom of the stump with BS
Different bone’s locations
• The obtained stress values are
correlated with the truncated bone
length.
• The asymmetric bone location causes
lower stress distribution.
• Stresses distribution in the stump with
PTB and 3S sockets are similar, and
Higher than with VASS socket.
• Force in 45 [deg] causes greater
stresses than normal force.
Basic socket (BS) stresses
Stress distribution in the stump within
different trans-tibial sockets
• Stresses are greater when walking on
both bone and soft tissue.
• the maximum Von Mises stress value
was measured at the top of the tibial
bone, below the knee.
• Asymmetric bone location causes
lower stress on the bone.
• Longer tibia applies less stresses on
the bone.
• VASS socket may reduce the risk of
deep tissue injury development in the
stump.
4 . Results
5 . Discussion
6. Conclusions
Short Mid Long
Different distance from the bone
end to the bottom of the stump
section - A cross - S socket A 3
The highest stresses
distribution in the stump
soft tissue is along the
Tibia.
Profile data examined at
2 cross-sections:
horizontal (A-A) and
vertical (B-B).
Short bone causes high
stresses at A-A section.
A A
A A
A A
B
B
A
B
Student name:
Guy Ateret
Department:
Medical Engineering
Advisor name:
Dr. Sara Naftali
Strains and stresses at sockets of
lower limbs - under the knee - prostheses
A
A
sections - Basic socket (BS) cross
sections - Asymmetric bone cross
PTB 3S VASS
tibial socket types - Stress on different trans