Types of knees for stance stability:
single-axis knee
- weight-activated friction knee
polycentric (four-bar) knee
- hydraulic knee
Types of knee friction systems for swing control
- constant friction
- variable friction (the prosthetist adjusts the knee's friction as the wearer's cadence and velocity increase.)
- Hydraulic knees are "cadence responsive;" their viscous resistance varies with swing velocity. Because of their weight and expense, they are justified for people whose walking patterns are vigorous and strong.
Last updated 11-2-2005Dave Thompson PT
return to prosthetic knee systems
single-axis knee
polycentric (four-bar) knee
return to prosthetic knee systems