I was involved in an RTA about eight years ago. My right knee cap was split in two in the vertical plane and had to be wired together. It took two attempts over several years to get the wires out of my leg and while they were there my mobility in the leg was less than 100% owing to discomfort in the knee. Once the wires were removed full mobility returned. I got the class 1 after all this happened. Essentially as long as you have full mobility and no instability in the legs you'll probably be OK. Good luck.