I Developed A Hematoma Five Weeks After Hip Replacement Surgery.

I developed a hematoma five weeks after hip replacement surgery. It is large and hard, like a golf ball, but causes no pain. The surgeon ordered a sonogram. The radiologist said there is little to drain, just a few small pockets and that she talked with my surgeon and they recommend doing nothing. They say it will absorb on its own, but will take a long time. I have no explanations how this could have happened. I did not fall and the surgery and recovery was seamless. I never needed a pain pill. It was posterior. I asked if there was something I should be doing to aid the absorption and was told no. What would cause this and should I apply heat and avoid massage? Could this occur from PT massage of my incision? From going off the aspirin and meloxicam? My only minor complication was an absorbable stitch made its way out the incision, causing that particular area not to close. Again, no pain, but the PA clipped it, it is now closed and I took a 14 day course of antibiotics. This was earlier on - around week three. The surgeon said my hip is fine and it is not related. He said, "You just had a little bleeding. I would't lose sleep over it." There has to be a cause so late after surgery?