Any orthopedic doctors who can give an opinion?

Hi I got injured on April 1st this year, I was working and picking up a heavy box, I tried to stand straight up and turn to set it down on my cart and felt a pain go all the way up my left leg and in my pelvis, I originally thought it was my hamstring because the pain was terrible in my thigh, but that pain has... show more Hi I got injured on April 1st this year, I was working and picking up a heavy box, I tried to stand straight up and turn to set it down on my cart and felt a pain go all the way up my left leg and in my pelvis, I originally thought it was my hamstring because the pain was terrible in my thigh, but that pain has mostly gone away and now it’s like in the back of my knee mostly, my orthopedic doctor thinks it’s a meniscus tear, but I wanted a second opinion. The pain feels like it’s a tendon in the back of my knee, but if I travel my fingers up the back of my thigh from where the pain is in my knee it’s still tender. Also I cannot straighten my knee out from a seated position, it feels like something is keeping me from doing so and it’s painful, but it’s not the pain that stops it from straightening, it feels like its straining when I try. It’s been 4 month and 2 weeks since the injury occurred. I have not received any treatment because of clerical issues with workman’s comp. and my workplaces physician told me she doesn’t believe anything is wrong with me since my MRI on my thigh came back negative for a hamstring strain. Given the pain information above what would you diagnose?
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