Otto Bock C‑Leg 3C98-2 Information For Users page 25

CAUTION
Non‑active safety mode. If the safety mode can no longer be activated, there is the risk that you will fall.
If the C-Leg does not switch to the safety mode (e.g. due to short-circuit due to water penetration), you must
actively stabilise the C-Leg at heel strike with your residual limb muscles until a prosthetist can be reached
or a prosthesis replacement be accomplished. Immediately contact your prosthetist.
CAUTION
Risk of pinching where the joint bends. Ensure that fingers and other body parts are not in this area when
bending the joint.
Function
Stance Phase and Swing Phase
The C-Leg is an electronic knee joint system with hydraulic stance and swing phase control.
Biomechanical analyses have led to the creation of an electronically-controlled knee joint which closely
matches the swing characteristics of the prosthetic limb to those of the sound limb. The C-Leg immediately
adapts to different walking speeds and provides knee stability the moment it is needed. At heel contact you
may notice the added hydraulic stance stability. Any unintentional bending of the knee that might occur when
walking on uneven terrain, etc. will be prevented. This knee joint makes it easy to comfortably walk downhill
or go downstairs with a natural gait, but for your own safety, always use a handrail when walking on stairs.
During every phase of walking, the C-Leg offers you safety, comfort and dynamic response, regardless of your
walking style, so you can think about where you're going – instead of thinking about how you'll take the next step.
In addition, you can switch the C-Leg to a 2nd/3rd mode, which allows for such activities as cycling (in 2nd
mode only), ice skating or inline skating. You'll need to discuss the use of the 2nd and 3rd modes as well as
the required settings with your prosthetist.
A new standing mode, which locks the knee in a desired flexion angle, can also be selected with the remote.
Switching between 1st and 2nd mode can be accomplished either by using the included remote control or by
bouncing on the toe. By quickly bouncing three times on the toe, the leg will change modes and then confirm
the change with a beep and vibration signal. You must confirm this immediately by lifting the extended pros-
thesis. The knee joint will now switch over and signal this through another beep and vibration signal. For your
security, the load shift resulting from rocking on the toes, required to initiate the mode switch, must precisely
match given guidelines, both in terms of load and time.
You can switch from 1st mode to 3rd mode and vice-versa by bouncing three times on the heel in a precisely
defined rhythm and with exactly the right amount of pressure. The C-Leg indicates that it has changed mode
by beeping and vibrating. You must confirm this immediately by taking the pressure off the prosthesis. The
knee joint will now switch to 3rd mode and signal this through another beep and vibration signal.
The load shifts resulting from bouncing on the toes or heel that are required for switching must precisely match
given guidelines, both in terms of load and time.
Note: After charging the joint, the C-Leg will always start in the 1st mode, regardless of the last active mode.
The remote control cannot be used to switch the C-Leg into 3rd mode.
CAUTION
Risk of falling if mode switching has not been performed. To avoid falling, do not forget to switch back
to the 1st mode as soon as you have finished your activities in the 2nd / 3rd mode.
C‑Leg Ottobock | 25