Otto Bock C-Leg Quick Manual

Quick Guide #3
C-Leg® User Training Overview
Use this guide as a checklist to ensure that all aspects of using the C-Leg have been reviewed with the user before
delivery of the C-Leg. Please remember to give the "User Information Sheet" to the patient.
A: Charging the C-Leg
1. Basic Charging Every Night
Plug the charger into the wall. Connect the charger to
the C-Leg. The C-Leg will vibrate. When charging has
completed, the yellow light will turn off. Unplug the
C-Leg and it will beep. The C-Leg is ready for daily use.
B: Training for the Gait Functions of the C-Leg
1. Disengagement of Stance Flexion Resistance
It may be necessary to manually lower the maximum toe
load threshold. When manually adjusting the Maximum
Toe Load feature, have the user flex the knee when
they have full weight on the forefoot and the knee is
in full extension. This will show the user the condition
that must be met for stance to disengage in the C-Leg.
Next, have the user stand with their feet side by side
(and then repeat with the prosthetic foot out in front),
have the user try to flex the knee easily. Since it won't
flex easily, the user will start to realize the criteria for
stance disengagement.
2. Stumble Recovery
While manually adjusting the Stance Flexion Damping
feature, in the parallel bars, have the user put the
prosthetic foot in front and test the resistance of the
knee by flexing the knee. The knee should have a slow
enough yield so that the users will have enough time
to catch themselves in case of a stumble. Testing this
feature in this manner can build confidence in the
reliability of the Stance Flexion Damping feature.
3. Stance Flexion
Stance Flexion is the flexing of the knee at Loading
Response that occurs during normal gait. This motion
helps to absorb shock and keeps the body's center of
gravity on a more natural sinusoidal pathway. The
Microprocessor Stance Control of the C-Leg allows
Stance Flexion to occur. For many experienced
amputees, Stance Flexion may not be a comfortable
feeling. This stems from the fact that with most
prosthetic knees, if the knee bends at Loading Response,
a fall is almost always imminent. Therefore, trust in
the reliability of the Stance Flexion Damping feature of
the C-Leg must be built-up over time. For many users
this only comes with use of the C-Leg in many different
situations. In many instances, Stance Flexion should
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only be introduced to the user after they have been using
the C-Leg for some time.
Alignment is critical to achieving proper Stance
Flexion. If the alignment is too stable, Stance Flexion
will not occur. Shifting the knee axis further anterior
or dorsiflexing the foot may help to create a less stable
alignment. A less stable alignment has the added benefit
of making it easier to initiate Swing Phase.
Foot selection is another important component of Stance
Flexion. The softer the heel of a prosthetic foot (shorter
heel lever), the less the tendency is towards Stance
Flexion. A firmer heel of the prosthetic foot (longer heel
lever arm) will encourage Stance Flexion. For example,
the 1C40 foot has a very long heel lever to encourage
Stance Flexion. A longer heel lever is also useful to
preserve momentum early in the gait cycle, as the user
does not "sit back" on the heel of the foot.
4. Swing Phase Initiation
Because of the flexion resistance to either initiating or
proceeding through Pre Swing that is inherent in many
other prosthetic knee designs, many users may show
poor gait habits through this part of the gait cycle.
a. Un-weighting the Prosthesis
This deviation is especially seen in users who have