Otto Bock 3R90 Instructions

The Otto Bock 3R90 is a modular knee joint built to be fitted to a prosthetic lower limb. The knee joint has a weight-dependent braking system that engages when the user's heel touches the ground and deactivates when the heel rises and the front of the foot reaches the ground. This design provides better stability for the user and allows a natural gait. The 3R90 is designed for amputees who have a mobility of grade 1 or 2, or indoor walkers or restricted outdoor walkers. The joint will support patients up to 275 lb.

Things You'll Need

• Hex screwdriver
• Flat-head screwdriver

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Instructions

• 1

  Test the knee joint before you make adjustments. Walk while you hold on to parallel bars to avoid a fall. Test the joint after each adjustment.

• 2

  Turn the left valve screw to the right with the flat-head screwdriver to increase the flex resistance in the joint. Increase the resistance if your heel rises too much. Turn the left value screw to the left with the flat-head screwdriver to decrease the flex resistance. Decrease resistance if the heel does not rise sufficiently while walking.

• 3

  Turn the right valve screw to the right with the flat-head screwdriver to increase the resistance when the lower prosthesis extends. Increase the resistance if the impact is too hard. Turn the right valve screw to the left to reduce the resistance. Decrease the resistance if the lower prosthesis does not move freely.

• 4

  Turn the set screw to the right with the hex head screwdriver to lower the sensitivity of the brake. Lower the sensitivity if the brake holds too long when the heel hits the ground. Turn the set screw to the left with the hex head screwdriver to make the brake more sensitive. Increase the sensitivity if the brake releases before the heel leaves the ground.

• 5

  Press the setting unit on the bottom of the joint and turn to the right to increase the tension of the spring for the mechanical extension assist. Press the setting unit and turn to the left to reduce the tension. The spring tension has five settings.