Non-Healing Wound of the donor area of Skin used for Grafting

My mother underwent a surgery in 2008. The skin from the thigh was removed and grafting was done on the stomach. But till date that is January 2010 , the skin has not completely healed, and every few days there are scapes , which peel off and the subequent red layer of the skin is revealed making it very painful. Opinions from 3 different plastic surgeons were that the skin from the donor area has not healed because more skin was removed then required. She does not have diabetes, but has weak kidney function so she cannot take high protein foods.
What is the solution to remove her from this agony and pain every waking moment ?