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DYNAMIC ALIGNMENT
The heel stores energy after initial contact, slowly releasing it at mid-
stance. The forward momentum generated by this action results in the
toe being loaded for optimum energy release at terminal stance.
The heel-to-toe action can be influenced by:
• Anterior/posterior positioning of the foot
• Dorsi/-plantarflexion
• Heel wedges (see Temporary Wedge Placement)
HEEL WEDGES
Heel wedges influence the heel to toe function. Alter the heel resistance
to improve foot response by adding a heel wedge. The small, medium
and large wedges can be interchanged to customize the stiffness and
achieve the desired functional characteristics.
Temporary Wedge Placement (Figure )
Place the wedge in the angle of heel and foot module.
Secure in position with tape wrapped around the foot module.
Heel too soft
Symptoms
• Foot comes to a flat position too early (user feels she/he is sinking
into a hole).
• Extra energy required to climb up over the toe.
• Toe feels too stiff.
• Knee may hyper-extend.
Actions
• Shift socket anterior (or foot posterior).
• Use a larger heel wedge.
Heel too hard
Symptoms
• Rapid heel-to-toe movement.
• At initial contact, the user has poor control of prosthesis.
• User feels minimal energy return.
• Knee may become unstable.
Actions
• Shift socket posterior (or foot anterior).
• Use a smaller heel wedge or remove wedge completely.
Permanent Wedge Placement
Roughen the upper surface of the heel with abrasive paper.
Apply adhesive on the lower side of the wedge only.
Locate in the foot/heel junction and position before adhesive sets.
For feet with split heel install the heel wedge then remove a thin slice in
the middle by cutting with a sharp knife through the split in the carbon
foot module. (Figure )
Instant adhesive is necessary to bond the urethane heel wedge. The
adhesive cures in - seconds.
HEEL DIVIDER
The heel divider should be placed in the last third of the split heel part. To
secure its position a drop of instant adhesive can be used on one side.
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