Healing rate calculation in the diabetic foot ulcer: comparing different methods.

The determination of healing rate in the diabetic foot wound is an important assessment parameter that is part of the overall clinical decision-making process in wound treatment. A number of methods that have been used to calculate healing, ranging from length and width measurement, surface area measure changes expressed as a function of time and linear advancement of the wound edge. The objective of this study was to compare surface area measures to linear advancement of the wound edge in 228 diabetic foot ulcers. Each wound was measured using the two methods and analyzed using linear regression to determine the best modeling of the healing process in these wounds. Results indicated that the total surface area change per day was superior to the linear advancement parameter in this group of wounds and that the area measurement was significantly more likely to predict the healing trajectory in the subgroup of wounds that took more than 28 days to heal. Contrary to expectations, the linear advancement method was correlated to initial wound size in the longer duration wounds suggesting that in these chronic wounds, differing healing phases render the surface area calculation method superior to the linear advancement parameter.