VGK knees provide intuitive control to patients. This control allows patients to live without barriers. The VGK’s patented hydraulic fluid technology ensures the knee stays in stance mode at all times, except when the knee enters swing phase. When the knee commences extension, the hydraulic fluid system immediately switches to stance mode, allowing the knee to recover from stumbles or walk downhill. This system uses the actual speed of movement of the fluids inside as a source of energy and information for adjusting resistance, keeping the rate of movement within comfortable boundaries.