Soft lump on front of my knee - no pain

Bones, joints and muscles
1

I have got a soft lump on the front of my knee, over 6 months. There is no pain, the only time I notice the lump is when I kneel. Even then there is no pain. I have been to the doctors and he has tried to reduce the lump by aspirating using a needle. After 6 goes the lump is still there. The liquid is now is thick blood. 

the doctor says to leave it alone, continue running etc, but if the pain come back then the solution could be surgery. Any comments

2

Could be an effusion. Take medical advice. Running? Have you had TKR?

3

BEING to the doctors, he has tried to drain the fluid 5 times by trying to suck the fluid out. But it just keeps coming back. There is no pain, even when running. The only time I know the lump is there, is when I kneel. Providing there is no pain, the doctors says keep running, be normal etc.