some of the symptoms are possibly nerve related. you cannot be certain that is is a simple knee problem if no one has tested neurodynamic maneuvers (slump, straight leg raise, etc) and i don't really see anyone considering that.

can you explain what you mean by "bubbling" feeling in the hamstring? is this what may also be called "tingling," "pins and needles," or "ants walking" or is it a different?

if neural elongation test is positive it makes half of the conversation a moot point. all medical professionals constantly miss referred lumbar dysfunction and call it a "hamstring strain." it could be a nerve, low back joint, or muscle among other structures that cause the posterior thigh pain. The hip or pelvis may also refer/send pain to the posterior thigh.

one cannot properly differentiate between the two without doing sufficient in-person testing. but, try this.

"slump test" - sit down, slouch into a poor posture position, look down (move chin toward chest), slowly straighten the knee (making sure to not sit up any higher out of the slumped posture (you should have someone gently hold you into the slouched position because most people accidentally sit up part way), and finally pull your toes up toward your nose (ankle movement only). if, at any point in the test you can move your ankle (point toes up and down via ankle movement) and it changes the way your posterior thigh feels, it is not likely your hamstring causing the problem and you more likely need nerve directed treatment or low back treatment.


good luck.