Snapping/popping knee when extending knee (pes anserine bursitis?)

Hello everyone. I'm interested in your quick opinion of my problem. I have an appointment soon with a physical therapist specialized in manual therapy. So I guess I'm not really looking for "full" advice, but just some views that may help/improve the advice and treatment I'll get from the physical therapist.

For a couple of weeks now, I have a "plopping" knee. When I extend my leg when in upright position (sometimes also in seated position), I can feel something snap back and forth every time I extend me leg. Initially, this is not painful, though after long walks (1+ hour), I have pain at the medial side of my knee. The pain is not specific to the site of the snapping tendon (see below), it spreads along the medial side of my knee. It's a dull, inflammation-like pain that gets a bit worse when putting pressure on the area.

The snapping seems stronger when I descend into a squat stance (though not painful). When squatting, the snapping occurs at the bottom of the position (full knee flexion), as well as at the top (full extension).

I'm quite sure that I've had this problem (or a very similar one, there was definitely "plopping/snapping") before, a few years ago (4-6 years ago). I visited a GP who sent me home because I didn't have pain at the time of the visit.

I started lifting weights one year ago. I do a lot of squats. Starting roughly 3 months ago, I started altering my stance during my squats. Following the teachings of a "famous" physical therapist in the fitness world (Kelly Starrett), I started pointing my toes more straight forward, and my knees outward, in order to create torque at the hip. I've never had knee pain or discomfort during or after squatting.

Armed with the body browser from Visible Body, I started exploring and trying to find out what part of the knee was actually snapping. I touched various areas of my knee while extending my leg. I have a feeling the snapping part is the tendon of the semitendinosus going over the semimebranosus, as I can feel the snapping more strongly with my fingers at the medial side of the back of the knee. Though it could also be the gracialis, I have quite a bit of fat on my legs and my knowledge and feeling skills with regard to anatomy are limited.

In this medial-posterior view of the knee, the semitendinosus is highlighted blue. The arrow is pointing to where I think the snapping is occuring.

Attachment 1182

I guess this could be "pes anserine bursitis", but really, I don't know what I'm talking about.

I could list more of my musings, but I'm not sure if they are helpful. Thanks in advance for your response.

Probably is your meniscus. Unlikely to be hamstring tendons in both the squat and extended knee positions. Physio should easily enough be able to see what is clicking provided you can reproduce it in the clinic.

Thanks physiobob, now that I check out the symptoms of meniscal injuries, that diagnosis makes sense.