Is your elbow locking a feature of ataxia?
My arms and legs 'lock out' for a few secs to a few mins but I have Dystonia mixed in with my Ataxia, my hands sometimes stay in a flexed position and feet in a tip toe position and have to put splints on to be able to put foot flat on floor and use my hands.
Not to my knowledge. Its quite hard sometimes to work out what is and what isn't a result from ataxia .You what to think everything whats happening to you is all down to are condition, but we still suffer from everything else, like everyone else. So i'd go and get it checked out by your doc, it could be something simple.