Hi,
A third opinion isn't a bad idea. With hamstring I tend to diagnose through exclusion. The majority of hamstring pain is related to the lower back. It is estimated only about 20% of hamstring pains are actual tears of the muscle. Taking into consideration your history, my first intervention would be to work through your lower back and gluteals and see if this does make a change to your pain.
The hamstring has a close relationship with the core. It is a muscle group that assists your gluts. Most people have some weakness through their gluts so the hamstring tends to be overworked and results in tears or fatigue. Weak gluts also overload the lower back.
Best of luck.
Rod
Fountain Gate Physiotherapy | Physio Narre Warren, Berwick, Hallam, Cranbourne and Beaconsfield.
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