How To Treat Severe Swelling Of Knees Due To Arthritis?

I have arthritic knees which can generally swell at times, but 2 wks ago I had a massive swelling just above my knee cap , over the last 2 wks the swelling has gone down quite a bit but my knee still feels week and tight , it appears that the swelling generated from an area to the right of the knee, above the knee cap, is this a quad or ?? I rested for a week butnhave started walking a lot more (I have horses) but it still feels a bit swollen and uncoordinated (sorry) what should I do?? Thank you