I wasn't suggesting you hyperextend on purpose. The body is an amazing thing and will accommodate and adjust for weaknesses by balancing itself in any way possible. Hyperextending your knees isn't especially good for the knee joints but it does keep you up and moving and off the floor. It could also be aggravated by weakness in your hip muscles. It's hard to say without seeing you in person. You do need to talk to your neuro and see if you can get a referral to PT. Just be careful with PT, don't let them overwork you.