Popliteal strain?

[violablue]

Usually popliteus trigger points are felt central or more often slightly medial to the posterior knee joint. Plantaris the same or slightly more central. Usually with lots of walking, running, skating type activities the popliteus can become involved. I've seen that often as a trigger for pain in the posterior knee. Hamstrings, yes. If your hamstring are tight, you can have pain referring into the back of your knee and into your calf.

As the other physios have mentioned, a lot of other issues can contribute, as well.

If you want to look more into trigger points as an issue check out:

Trigger Point and Referred Pain Guide

And most especially Trigger Point Therapy Workbook; Your Self-Treatment Guide for Pain Relief

The webpage doesn't get into the popliteus, but the reasonably priced book does so better than any I've seen to date.

Wishing you good fortunes with tracking down your problem.