Left inner calf muscle atrophy. noticed about 2 years ago that it was smaller and a little weaker. after a minor calf muscle tear now it's like it's completely gone. it doesn't even respond to tens / ems stimulation. i think piriformis syndrome..?

First. Your Piriformis muscle is located in the hip area not near the calf. It sounds has though you received a work up concerning this. Have you seen a neurologist ? You give a condition of a muscle that has lost its nerve connection. How did this occur? See a neurologist for care. A neurosurgeon might be able to reconnect muscle if not too late.