Can a Seroma Remain a Year & 9 Months After a Panniculectomy, then Abscess?

I had a panniculectomy & hernia repair in Oct 09. I had pain in an area of of my panniculectomy scar. In July 11 an abscess developed in that area & had to be surgically cleaned out. The wound was left open & had to packed. It has healed & the pain was gone. About 2 weeks ago, I started having the same type of pain right above the area where I had the abscess & the area swells. How common is this??