An evaluation of three wound measurement techniques in diabetic foot wounds

Approximately 80% of diabetes-related amputations are preceded by a diabetic foot ulcer (1,2). Wound measurement is an important component of successful wound management (3–6). Accurate identification of the wound margin and the calculation of wound area are crucial (7–9). Although more complex methods of wound measurement exist (planimetry, digitizing techniques, and stereophotogrammetry) (4,10–14), current practice focuses on wound measurement using simple ruler-based methods or by wound tracing. Ruler-based schemes tended to be less reliable in wounds >5 cm2 (11). Various mathematical formulae (including the calculation of area based on the formula for an ellipse) have been proposed to improve accuracy in wound surface area calculation in wounds <40 cm2 in size (10,11,15–17). The aim of this study was to evaluate and compare three wound measurement techniques: the Visitrak system (Smith and Nephew Healthcare, Hull, U.K.), a digital photography and image processing system (Analyze, version 6.0; AnalyzeDirect, Lenexa, KS), and an elliptical measurement method using the standard formula (πab) for the calculation of the area of an ellipse.