Disclosed is a prosthetic knee appliance having upper (20) and lower (40) leg elements with a single-axis, articulating joint (60) therebetween controllable with an electric knee-lock mechanism (80). A tilt-switch (90) located within the prosthetic knee can facilitate activation of the electric knee-lock to lock or unlock the joint when the lower leg element is in a pre-determined position. A remote control can provide external locking control of the articulating joint. A pressure switch (100) can ensure that the free-knee is locked only when the lower leg element is sufficiently extended relative to the upper leg element. The mobility of a free-knee system combined with the stability of a straight-leg prosthesis can be advantageous for pre-ambulatory pediatric patients.
