I think everyone overlooks those darn steps on a MH.
I started out full timing with 2 good knees. Within 6 months my knees looked like footballs and I could barely get in and out of the MH.
Thinking old age was going to get me first before I could even get started on RV'ing.
Pulled off the road for a death in my family to help settle their estate. Surprisingly without really thinking about it my knee pain went totally away. Fast forward got back on the road and the pain and swelling came right back. No brainer for me that it had to be something to do with the MH.
RV steps are narrower than our feet which without really thinking about it we twist our legs and body ever so slightly as we exit the RV to fit on the step. Over time if you do it enough puts stress on the knees.
I went on a mission of trying to find a way to replace the RV steps with something that supported my legs to be able to walk 'straight' out of the MH. And be portable enough to use.
Once I changed how I exited the RV all my knee pain disappeared.
You will be surprised that by simply replacing those narrow RV steps how quickly your leg and back health will return to normal.