Hi, I am a 23 year old female and an ex gymnast, and now do trampolining a few times a week. 4 months ago I was diagnosed with a stress fracture to my spine (L5) and so am just rehabbing and getting back to sport. I also enjoy running and going to the gym. I recently noticed a protruding lump on my right knee, especially when I bend the knee. The lump appears on the lateral part if the knee along the joint line (according to my physio). It is quite a large lump and quite squishy to touch. The knee does not appear hot to touch or red. It has started to hurt in this area when running and jumping, quite a sharp pain, and aches after activity. I would like some advice as to what it could be and whether I could do any damage by carrying on with sport. I am a very active person and as I have been out for a long time with a back injury I don t want this to prevent me from getting back. Thank you, Amy