Swelling/fluid in the back of my knee

[Blossomhill]

I posted a while back as had it in the front of my knee. Went to gp and had testing for arthritis including bloods tests and x-ray, all come back clear.
Started to have pain yesyerday and the back of my knee seems swollen/puffy (same one)
Anyone else had this? Should I be worried?

I get weird aches in my knees, particularly when there's a change in the weather. I've never bothered getting it investigated, just put it down to old age! do you take ibuprofen for it normally?

my mum has had this for years! she is now having a partial knee replacement!

MTS - I take something the gp prescribed which is a bit stronger

Starlover - Oh no I hope I don't need one of those done. Did they ever give it a name?

yeah hers was actually caused by ligament damage and osteo-arthritis. she has just had an operation where they poke a camera in and have a good look around to see what's causing it... before that they didn't really know 100% what it was.

i am sure there are other explanations as well though...

I just think what can it be if all tests came back negative???