Checking The Socket After Bench Alignment - Otto Bock C-Leg 3C98-3 Instructions For Use Manual

Mounting the knee extender
The knee extender has to be used for bench alignment of the prosthesis. This ensures the recommended sagittal
positioning of the prosthetic components – the foot, socket and knee joint – relative to each other and therefore
offers the full functionality of the knee joint.
1) Check whether both 8° flexion stops are mounted on the knee joint (see page 31).
2) Turn the knee extender adjustment screw counter-clockwise, setting the knee extender to the minimum height
(see fig. 4).
3) Extend the knee joint.
4) Set the knee extender onto the hydraulics housing and slide it in to the stop (see fig. 5).
INFORMATION: Check whether the two positioning lugs on the upper section of the knee extender are
behind the flexion stops (see fig. 6).
5) Turn the adjustment screw clockwise, extending the knee extender until it touches the flexion stops (see fig. 7).
6) Insert an Allen key (size 4) into the adjustment screw and continue turning the adjustment screw clockwise
70 Ncm/10 full turns.
→ Now the knee joint is in the correct position for bench alignment.
Removing the knee extender
1) Insert an Allen key (size 4) in the adjustment screw and turn it counter-clockwise, setting the knee extender to
the minimum height.
2) Remove the knee extender.

7.1.6 Checking the socket after bench alignment

After bench alignment, verify that at maximum extension and maximum flexion the distance from the socket to the
knee joint is not less than the minimum. A collision of the socket with the hydraulics or frame can cause damage to
the knee joint.
INFORMATION
If the fitting with a knee joint of a previous generation such as the 3C100; 3C105; 3C98-1/3C88-1;
3C98-2/3C88-2; 3C95/3C85; 3C96/3C86; 3C98-2/3C88-2 was modified to use this knee joint (3C98-3/3C88-3)
without fabricating a new socket, this verification is mandatory. The available space is reduced by approx. 2 mm
when the 3C88-3 or 3C98-3 knee joints are used compared to knee joints of previous generations.
Verification at maximum flexion
Verification at maximum extension
C-Leg 3C98-3/3C88-3
If the distance between the socket and hydraulics is not sufficient, the hydraulics
may be damaged. Check the distance as follows:
1) Bring the knee joint with socket to maximum flexion.
2) Check the available distance between the hydraulics and socket. It must be at
least 3 mm.
INFORMATION: If the distance is less, a flexion stop has to be installed or
an existing flexion stop replaced with a larger one. For information on the
flexion stop, see the next section.
If the distance between the socket or system components such as a rotation adapter
(4R57) and electronics is not sufficient, the electronics may be damaged. Be sure to
follow the system component instructions for use.
Check the distance as follows:
1) Bring the knee joint with socket to maximum extension.
2) Check the available distance between the electronics/top edge of the installed
protective cover and the socket or system components such as a rotation
adapter. It must be at least 5 mm.
INFORMATION: If the knee extender is used to verify the distance, note that
this is only permissible if the 8° flexion stops are installed.
Preparing the product for use
29