18 months ago I broke both bones in my right leg and dislocated my ankle so I sympathize. One thing I have learned is to make sure you are sitting directly in front of the needle not off to the side. I also put my foot pedal on a book and a non slip pad under it so it doesn't move. I also bought a neat but inexpensive chair (99.00) that I had tried at my LQS and is comfortable to sit in for long periods of time. Make sure to have something to rest your left foot on so it is even with your right,