Although the knee joint is passive, which means it cannot actively initiate
movements, negotiating stairs step-over-step is possible.
This function must be practised and executed consciously.
1) Lift the extended prosthesis off the floor.
2) Immediately after lifting the extended leg off the floor, extend the hip briefly
3) When sufficient knee flexion has been achieved, the knee joint increases
4) Set the foot onto the next step.
5) Support yourself with your hand on the contralateral side. A smooth wall
6) Bring the knee into extended position. When the knee joint is fully exten
7) You can climb the next step or continue walking normally.
8.1.8 Overcoming obstacles
INFORMATION
To use this function, it must be enabled by the prosthetist. It also has to be activated using the
cockpit app or remote control (see Page 74).
The stair function can also be used to cross obstacles:
1) Lift the extended prosthesis off the floor.
2) Briefly extend the hip.
3) Quickly flex the hip. This causes the knee to flex.
4) With the knee flexed, step over the obstacle.
and then abruptly flex it. This requires a sufficiently secure hold in the
socket and a certain level of residual limb strength.
→ This whip motion flexes the knee, because the knee joint automatically
recognises the movement and sets the flexion resistance to minimum.
INFORMATION: Take note of people behind you before executing
the whip motion.
extension resistance so that there is enough time to position the foot on the
next step before the knee joint is extended again.
The support area for the foot on the step must be large enough that the
heel does not extend back too far over the edge. With too little support
area, the lower leg would extend too early and position the leg too far
backwards. In this phase, the knee joint has already set the flexion resist
ance to maximum (blocked). The knee joint can no longer be flexed but
only extended. This ensures that the leg does not buckle if the hip strength
is not sufficient for the extending motion.
will also work. This lateral support is intended to prevent the residual limb
from twisting in the socket. Twisting can lead to unpleasant surface ten
sion between the skin and the socket. Lateral support also improves bal
ance.
ded, the initial position has been reached.
With sufficient knee flexion, the extension resistance is increased to allow
enough time for crossing the obstacle.
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