Can testicular torsion lead to low testosterone?

Maybe: It all depends upon how badly your testis was harmed. Realistically, you actually only need one testis to supply enough testosterone & sperm. And since only one testis typically undergoes torsion, even if that one is damaged enough to require removal, you should still have enough from the other. You're hosed only if both testes twist at same time w/o getting treatment soon enough.