Hello Stephen,
Welcome to E-Budo. Actually, I have memories of you posting here before.
Can you tell us what kind of injuries you suffered, if it is not too private? I ask because I once hit an old lady crossing the road. I was on my Yamaha FZR 1000, but was barely exceeding the speed limit (perhaps one or two kph over). Without thinking I executed an ukemi, which was clearly very good, as it turned out, and stood up on the road in hanmi, just like in the dojo. I had no injuries, but the suit I was wearing was scratched and torn at the shoulder. The bike was repaired, but I got rid of it soon afterwards.
More relevant to your situation is the operation I had on both knees to remove part of the meniscus. I did some physiotherapy, as prescribed by the hospital, but this was done too severely and the surgeon told me I would have arthritis when I was older; as it has turned out. I will be 64 later this month and seiza is becoming increasingly difficult.
You will find discussions on budo and the body elsewhere in this forum.
Best wishes,
PAG
Peter Goldsbury,
Forum Administrator,
Hiroshima, Japan