I stumbled without any trauma or fall. Thigh muscle felt like it was tearing & there was a lot of pain, what would cause this? I do have scoliosis and a compressed nerve in my lower back. I was told this was the cause of these incidents, but this was def

Could be unrelated. It could be unrelated. However i would check to make sure your knee works normally. You can tear your quad tendon which can result in significant disability if not picked up quickly.
You . You may have a partial tear of your quadriceps muscle. I don't think it is a back problem at all.