Calf Muscle Pain And Fever. Undergone Stent Procedure. Possible Reasons?

hi doctor my father aged 54 years is saying that he is getting calf muscle pain on and off.but his muscles are not tight.they are normal.he is diabetic from past 10 years and 2 years back he undergone stent procedure for heart .recently 2 months back he got fever from then onwards he is getting calf muscle pain on and off?