The hinges have bearings in them. The general idea is you slip your leg in, wrap velcro around the straps, and your ankle hovers a few inches above the ground. A shoe riser goes on the other foot, and you walk with a cane.
The device worked as intended, but proved to be cumbersome to wear for long periods of time. It is also still easier to get around on crutches. The upside is, it did allow her to walk for short periods of time without crutches. This was version Mk I. We did three iterations before moving on to other projects