For TT patient, WB on pressure tolerant areas. What are those areas?
patellar tendon,
pretibials
posterior distal aspect of the stump (gastrocs)
popliteal fossa, lateral fibula (not fibular head) and the tibial flares.
PTB total contact sockets help to do what?
- Ensure good venous return
2. Help prevent distal pooling
Why is the foot 1/2” medial to center of the socket in bench alingment?
brings them to a normal amount of varus at the knee
Why must valgus at the knee not occur?
This to ensure that there are minimal forces on the popliteal nerve as it courses behind the fibular head.
Why is the knee flexed to about 5 degrees in the socket?
enhanced patellar tendon weight bearing
decrease lumbar lordosis
If the socket is too far anterior (foot too far posterior), where will there be excessive pressures?
anterodistal and posteroproximal pressures
If the socket is too far posterior (foot too far anterior), what will occur at the knee?
hyperextension = knee instability
What will the head, arms, and trunk do for foot stability during stance phase of gait?
Move the body over the foot for stability
If the foot is too far anterior (socket too far posterior), where will there be excessive pressures?
anteroproximal and posterior distal pressures
Where is breakdown more common in a TF amputee?
groin, hamstring tendons, adductor longus tendon
If you see heal strike into midstance and flexion, what direction should you move the foot?
More anterior
If you see hyperextension through gait stance, what direction should you move the foot?
posterior
What is TT foot outset? How do you correct it?
- Foot too far lateral - pressure at lateral proximal and medial distal areas
- Correction: translation medially of the foot, laterally of the residual limb
What is TT foot inset? How do you correct it?
- Foot too far medial - Pressure proximal medial and pressure distal laterally
- Correction: slide foot more lateral or socket more medial
What type of stability is the most important for a TF amputee?
Knee stability
Minimize rotation of the prosthesis for a TF amputee by doing what 3 things?
- maintain pelvis in a posterior tilt on the posterior rim
- incorporate ischial/gluteal weightbearing/ containment
- the adductor longus tendon is secured in a groove in the socket
Without a good lateral wall support, what type of gait will you see for a TF amputee?
likely ambulate with a trendelenburg-type gait and expend significantly more energy
TF socket designed to do what 3 things for good lateral wall support?
- provide abductor contact with socket
- provide points of force in a proximomedial direction and distolateral direction to prevent lateral shifting of the prosthesis
- place the center of the heel under or slightly lateral to the ischial tuberosity to promote a slight valgus at the hip for increased stability
If the foot is placed too far medially, where will there be excessive pressure?
in the groin and distal lateral aspect of the residuum.
Alignment of a TF amputee in the sagittal planes helps ensure what?
helps to ensure that the knee will not buckle during stance phase and weight bearing
5 degrees of flexion (floor reaction force anterior to knee joint) is built into TF amputees the do what 2 things?
- enhance the firing of the gluteal muscles
2. allow the person to extend the hip without having to go into a hyperlordotic posture
If the foot is placed too far laterally, where will there be excessive pressure?
excessive pressure proximolateral and distomedial
What basic fit principles are you looking for in a static checkout?
- Soles of feet flat (no dorsi or plantar flexion)
- Socket fit well (put playdough into socket and make sure they make full contact so there is no edema)
- User comfortable
- Is suspension adequate
- Are bony landmarks level
- Vertical pylon in stance
- Are tissue rolls minimal
- Gapping between leg and socket
- Does residuum have distal contact
- Normal heel center spacing (2-4 in quiet stance)
- Is knee stable in stance
