Ossur TOTAL KNEE 2000 Gebrauchsanweisung Seite 9

• If patient is walking fast and you observe excessive heel rise, increase
resistance of Valve F until heel rise has normalised.
• Use Valve H to smooth flexion resistance changes between initial
flexion and 60°.
• Increase swing extension resistance with Valve E until terminal impact
at full extension is reduced. Patient should feel a slight bump at full
extension as Geometric Lock is activated prior to heel contact.
Excessive swing extension resistance will prevent knee from moving
into full extension and eliminate activation of Geometric Lock.
• Fine tune Valves F and E until a smooth and secure gait pattern is
achieved for slow and fast walking speeds.
HEEL RISE / INITIAL FLEXION – VALVE H (Figure 9 & 10)
Generally it is not required to adjust Valve H, unless the patient's walking
speed is slow and excessive heel rise is observed.
Valve H can also be used to fine tune the resistance between initial
flexion and 60°.
To adjust Valve H remove the „sticker" (Figure 10).
caution! Over tightening valves or flexing knee with all valves
completely closed may damage valves.
Bumper adjustment
• Try different bumpers and select the most comfortable one.
• Final bumper selection may vary from bumper indicated for patient's
weight according to table.
• Soft bumpers increase the locking momentstrength of the Geometric
Lock and increase stance flexion motion.
• Hard bumpers decrease the locking moment of the Geometric Lock
and decrease stance flexion motion.
• Foot selection influences bumper selection.
a. For soft heels, choose a softer bumper.
b. For hard heels, choose a hard bumper.
Shim adjustment (Figure 7)
Adding shims changes the release point of the Geometric Lock allowing
for swing phase knee flexion. This affects knee stability and ease of
walking and sitting. The shims are thin plastic plates which are installed
underneath the bumper to adjust its height. A change in height affects
the knee's release point.
• More shims: easier release into swing flexion and decreased stance
flexion
• Less or no shims: increased safety, increased stance flexion and
delayed release into swing flexion
note: There are two different types of shim. The thicker ones are 0.76mm
thick and clear, the thinner ones are 0.38mm thick and grey. We do not
recommend using more shims than those two combined. Adding more
shims can eliminate the Geometric Lock and affect stability of the knee
during stance.
Gradually increase shim thickness until the user feels premature release
of the knee. Reduce shims until the user finds a balance between security
and release point. Please make initial adjustments inside parallel bars.
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