The Bionic Leg provides motorized assistance with extension (straightening your knee), which kicks in when you're standing up from a seated position, swinging your leg forward between steps, and going up stairs. It also provides resistance for flexion (bending your knee), so it kicks in when you're lowering yourself down to sitting, squatting, or when you're going down stairs. It enables patients to move without having to compensate in ways that would slow down their rehab or possibly cause other complications.