Originally Posted by
Leisesturm
You need a twist of some kind to get out of the MagLocks. Even set for minimal grip, the magnets have their strongest pull straight on. Platforms with pins seem ideal for your situation.
Not to answer for OP as he is above knee...my own issue with platforms in general is that without feel in your foot and no ankle for correction there is a tendency to move around on the platform while pedaling and this exacerbates when having a fast cadence. I can only imagine it magnifying even more without a knee to feel what is going on. I would imagine that foot retention for that condition is even more important.