Friend had torn meniscus surgery and when he walks on his foot, his calf hurts. he says it only hurts when he walks on it. what is making it hurt?

Not sure: Your friend needs to be re- examined by his/ her orthopedic surgeon. An ' answer' in this forum is pure speculation w/out examination of your friend.Calf pain could be due to gastroc. 'soreness', fluid leaking into the back of the knee post-operatively; blood clots is a more serious cause if calf pain. Have him see his/ her ors or go to the E.R. If pain is worsening. Best of luck!