Maybe some pads... Like the Michelin Tire guy...




Or, perhaps a full body armor Iron Man suit



Anyway, if a fall is so serious, I would certainly consider pads.

Skateboard pads? The problem is that they protect the knees and elbows, but don't seem to do wrists. They might give more comfort in a fall though, and thus less likely to put the arm out. There are good wrist braces that might help a bit too.