Musicians with Dystonia Bulletin Board

So here's my problem - my M finger is the dystonic one (used to stick out rigid and be un-usable, now it works again) and the A finger will overcompensate by curling in towards the palm when M should be playing, in certain configurations. Main problem is where I follows M in a sequence, so for example in a standard P-A-M-I, after A plays and its M's turn, A will continue towards the palm with M being a little lazy to get going. The faster I go, the worse the problem, the slower I go I get to a point where I can fully control the motion of M and A barely flickers

Here's one of many little fixes I developed which help the recovery process and has helped me get more speed into that arpeggio.

Practice P-M-I arpeggios (which would elicit the same problem in A) slowly on open strings, with say P on the 4th string and IM on 3rd and 2nd respectively.

Play P, then just before you are about to play M, plant A lightly on the top string.

Continue to play M, then I in the usual way with A still planted. Release A and begin the sequence again.

Repeat this, relax and really feel what happens when A touches the string each time in the sequence. It should feel slightly confusing as suddenly you are interrupting the compensatory movement just before it kicks in, and giving your brain a clear signal as to which finger is which and where things are (proprioception).

Do this a few times, now play the arpeggio without the A plant, then switch back again. See if it feels easier?

Play with this process and with the right mindset you can help to unlock a compensatory finger's established pattern.

Hopefully the above is clear enough so that you can apply the principle to any dystonic problem in your hand that involves a compensatory finger, but it does require you to fully understand what is happening in your hand.