7.1.2 Walking
Initial attempts at walking with the prosthesis always require the instruction of
trained, qualified personnel.
The knee joint is locked in the flexion direction. Therefore, proceed as you
would with a rigid knee joint.
7.1.3 Sitting down
The prosthesis makes it possible to sit down without manual unlocking. Here the adjustable flex
ion resistance of the hydraulic unit provides support while sitting down.
Hand support is recommended while sitting down, e.g.:
• Support on the armrests of the chair
• Support on the handles of a wheeled walking frame
• Use of forearm crutches
• Use of a cane
Sitting down
1) Stand 5 to 10 cm in front of the edge of the chair.
2) Place both feet side by side at the same level.
3) While sitting down, put even weight on both legs and push the pelvis in
7.1.4 Sitting
In a sitting position, i.e. when the thigh is close to horizontal and there is no
load on the leg, the knee joint switches to low resistance in both the flexion
and extension directions.
If the load on the prosthesis is not adequate, the leg remains extended while
sitting down. Due to the nearly horizontal position of the lower leg, damping is
reduced automatically and the lower leg drops down on its own.
7.1.5 Standing up
Notwithstanding low damping while sitting, the prosthesis supports standing up.
Damping is increased after rising from the seat. From an angle of approx. 45°, the knee joint iden
tifies a "standing up process" which results in what is called "pre-locking" in the flexion direction.
This function makes it possible to stand up with pauses in between. The joint fully supports
weight during these pauses. If standing up is aborted, the "sitting down" function is activated
again.
The joint is locked after fully standing up.
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While standing up, the edge of the chair should not yet touch the hollow of
the knee nor press on the lower leg.
the direction of the backrest.
This causes the weight to shift to the heel and the prosthesis to tilt back
ward, which makes the knee joint switch to "sitting damping". Support is
therefore provided while sitting down.