FIOR & GENTZ NEURO MATIC Manual page 33

Problem
The system joint does
not unlock.
The system joint does
a ratching noise in
swing phase.
The system joint can-
not be switched into
Lock mode.
The system joint can-
not be switched into
Free mode.
Cause
The leg was put into cast too extended. There-
fore, the patient cannot apply the necessary
extension moment to the orthosis to unlock the
system joint. Ventrally, at heel lift, you can see
an obvious opening between upper and lower
part of the system knee joint.
The extension stop damper is too long. Thus,
the extension stop damper is compressed to
such an extent that the necessary extension
moment to unlock the system joint is more
than the patient can apply.
As the patient's steps are not long enough, the
dorsiflexion stop is not reached at heel lift.
Thus, the knee extension moment to unlock the
system joint cannot be applied.
The dorsiflexion stop is reached too late
(see paragraph 11.1).
The forefoot lever of the foot piece does not
achieve its effect on the knee extension.
The proximal, dorsal thigh band transfers flex-
ion load when a leg is set back.
The spring force for lifting the foot is too weak. Increase the spring force.
The patient is wearing another shoe.
The wire is too long (adjusted too secure).
Load is applied to the extended orthosis.
The system joint was still locked in Auto mode
at the time of switching mode.
Solution
To increase the flexion, mount
the 10° joint's upper part to the
NEURO MATIC system knee joint
as well as the 10° extension stop
to the supporting knee joint and
check the basic alignment.
Cut the extension stop damper.
Adjust the dorsiflexion stop in
such a way that the forefoot lever
causes a knee extension moment.
Adjust the dorsiflexion stop until
the produced orthosis meets the
correct basic alignment.
Check the orthosis' basic align-
ment. If the system ankle joint has
a dynamic dorsiflexion stop, you
might need to insert a stronger
spring unit.
Remove material from the upper
thigh band area.
Check the shoe's heel height as
well as the basic alignment.
Shorten the wire.
Let the patient take the load off
the extended orthosis.
Let the patient apply an extension
moment to unlock the orthosis.
33