Hi Matthew -
I tripped a lot when I was a kid (well, actually, a fair amount most of my life!). My family thought I was clumsy, and the doctors said I was clumsy and lazy. Charming, eh? I wasn't diagnosed till I was 54, because no-one believed my "stories"!
Anyway, my calves have been enormous since I was about 3, and I always felt like I didn't pick my feet up well enough to prevent tripping. But I began doing stretches when I was quite young, and I never really had significant foot drop. Maybe it would help you a bit.
Stand in a doorway, and put your feet in a sort of lunge position, one slightly behind your torso, the other ahead. Lean onto the forward foot with your foot flat and knee bent, and keep your back foot flat on the floor. It isn't easy at all, but if you are gentle and go slowly and do it for 5 or so minutes a few times a day, it does (for me, anyway) help to relieve some of the tightness.
I also lean facing against a wall, lean on table tops and over the backs of chairs and sofas - even when I'm cooking, I will lean in towards the counter or sink and do some stretches. For me, stretching has become second nature. It sure doesn't stop the tripping and other crazy myotonic stuff, but it helps.
I do a lot of stretching - my arms/shoulders, my neck, just all over - it makes me feel better. So, just a thought! (I also don't think orthotics/braces will help - one of the things I have always found with MC is that my muscles fight against any type of restriction - I can't help it, and it is pretty much subconscious! lois
Type of Myotonia: Myotonia Congenita, Becker's type