Hmm, I never really thought about this much, but there is an interesting (if old) precedent. Back in the 1950's my brother had a condition called Legg-Calve-Perthes disease, which is a temporary necrosis of the femoral head. A brace was used to keep weight off the joint, the pelvis rested on a frame or the abdomen was wrapped in one, and the brace, with a shoe attached extended below the foot. Needless to say, it was a clumsy device, but the only other treatment at the time was a-frame casting for up to 2 years.
Recently, my friend was fitted with a similar device for 6 months after hip replacement because she had traumatic tears in her muscles and a damaged tendon, which mad her hip extremely unstable. With the brace she was able to stand and walk for short distances, safely & without pain.
If I was looking for information, I would start with a teaching hospital specializing in orthopedics...
Sue