Timely,
I hear you on the yoga. My experience has been that a good yoga teacher will always tell students to hold on to a table or chair for balance when needed and to only move as far as is comfortable. I found a bunch of videos with the 12 poses, some better taught than others. Your treadmill idea sounds great, perhaps a PT office would have a recommendation.

Morning timely~
I'm glad that you're seeking out info from others in situations similar to your own. There is so much info out there to assimilate and find useful.
I also have severe osteo and am not taking meds for it..but doing a lot of other more 'natural' things that vibrate with my personality and knowledge. I have a vibration plate and use it at the lowest speed. It's also good for shaking up cans of paint! I also have bad knees and can't do any of the squat types of exercises. I fear now though that I have weak muscles in my legs because I stay away from things that exacerbate my knee pain. I'm going to look into going to a gym with all the great equipment to try out. I know that there are treadmills with hand rails..so this would work well for you. I now wear a little pedometer so I can keep track of my steps and mileage..it keeps me moving! I walk with walking sticks, which takes a lot off of my knees as well as being an aide..giving me support when I walk. I'm working up to more challenging walks to gain more strength in my upper leg muscles...and arms as I use the sticks like I would an elliptical.
Since I have compression frax's in T-8,9,10....standing up as straight as I can also helps. I also have a far-infrared belt that I use when my upper back pain gets too much to deal with..that really feels good and I can avoid taking any meds for the pain that way.
We have to be wise about our weakened bones and take care not to make things worse, of course. Getting out in the sunshine and walking boosts my day ...I can't wait to go out each day and 'work it'...some days I pay for this..but all in all...at 79+, I'm happy with what I'm doing.
The medications for osteo scare the crap out of me...too many contraindications for me to wrap my head around it. Peace of mind is of utmost importance now..as well as not causing more harm. Now..if I get an odd jaw pain..I don't automatically wonder if this could be the osteo medications??? I take a lot of natural supplements and feel better for taking responsibility for my health picture. I wish you the best...do what feels right for you.

to timely:
You are mistaken about vibration platform. It is low frequency vibration and it does not contribute to worsening of knee arthritis. I am using the platform for 2,5 months and I have knee arthritis. I have not noticed worsening of my arthritis pains or more problems when I walk.