Can you please tell me how far proximal the PES Anserine bursa would extend when distended with effusion? I am wondering if it comes to the medial joint line/meniscus level? Also, is it likely to compress with sono palpation?
I had a case where I was convinced that it was PES bursitis, but it turned out to be a ganglion. My mistake was to not follow it distal to the PES insertion/ genicular NVB, also I did not try to compress it.
Yes, the pet anserine bursa can become very large when it is distended with fluid in a similar way to the iliopsoas bursa or the sub-acromial sub-deltoid bursa.
As in the hip it can be a little tricky to define if it is a para-meniscal / labral cyst of a bursa that is distended.
Some helpful clues are to try and track the fluid collection to it’s source and also to check for compressibility. A bursa is generally somewhat compressible and a para-meniscal ganglion is not.
It can certainly distend large enough to reach the medial joint line.