Hi Benn,
You could try a sports massage to try and loosen the muscle up. But the most important question to find out is, are you stretching your quad effectiveley. When I ask a patient to show me a Quad stretch with no guidance, most do it only half right. Has your physio checked you are doing this correctly.
What sort of treatment have you had from your physio? How did you know you had torn it the first time, what symptoms did you have? Last one for now, any back pain either previously of with this injury?