... What were you wanting to achieve by stationary bike riding?
...
First goal, I'd like to spin a little, very little resistance, just to make sure that the pedaling movement and that range of motion in my hip, along with being on a bike saddle, is okay and doesn't cause any hurt (during or after). If that's okay, then maybe 15-20 min several times a week. I think that would kind of confirm that I would be able to be a cyclist again--which would be a nice psycho-boost.
Second, I might not be expressing this right, but I think you have to show the damaged/weakened/healing parts what they're expected to do. My rehab girl has a protractor and measures throughout, and I most always gain range of motion over the 50-60 minutes of a session. I'd hope that pedaling would "show" my hip what it needs to be able to do.
My doc here, the rehab girl, and another person have cleared me for stationary cycling. This other guy is a retired bone doc who has done similar surgery, and is also a cyclist. He said:
From the hip/pelvis studies you posted it was a severe acetabular fracture and I think they did a good job reconstructing it. With that type of impact the bearing surface of the joint is usually severely damaged beyond the ability to repair itself and severe arthritis usually results. People vary enormously in the way they tolerate the joint damage and some can go quite a while, others not so long before the hip needs to be replaced because of pain and loss of function. They appear to have done a good job of preserving bone stock for a future replacement so I think you are good there.
One of the most important things in the prognosis long term is maintenance of range of motion and strength as much as possible as well as weight control. I think stationary cycling and water walking/swimming are ideal. Cycling especially puts the hip through a range of motion and kind of molds the joint surfaces and promotes movement of joint fluid which is how whatever healthy cartilage remains gets it's nourishment.
I would say try to stay close your normal seat height if possible and adjust as needed by what your body tells you. Stay in easier gears spinning and use it as a way to smooth out range of motion and getting your heart rate up rather than actual strength at first. If all is going well you can start doing some gentle intervals with bigger gears later on for strength.
It is often more than a year before things start to plateau and like i said there is enormous variability in how folks rehab from these serious injuries. Being thin and fit and having that mindset before the trauma usually correlates with a better outcome after and a longer period before additional treatment such as a hip replacement is needed. From your photos it looks like you fit into that category.
So hip replacement may eventually be needed..., after some severe arthritis... Yuk!
Obviously I don't want to botch it (and I'm not a pain = gain person), and would back off or stop if something didn't feel right. But the way the doc puts it there, I should be doing something.
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@macrophotofly I did once have this thing, was fortunate to get rid of it for about half what I paid:
Vision VR 60, iirc