Toward Objective Wound Edge Classification in Clinical Practice

Wound edge assessment is a key component of chronic wound evaluation, but it remains highly subjective and affected by inter-observer variability, particularly when performed on two-dimensional clinical photographs. We retrospectively analysed 1 860 wound images acquired during routine clinical practice and independently annotated by four expert clinicians. An automated image-analysis pipeline was used to segment the wound, standardise the peri-wound border region, and estimate the three-dimensional profile of the wound edge. We first tested whether geometry-derived edge profiles alone could reproduce clinical wound edge categories. We then evaluated whether adding global visual descriptors of wound shape, colour appearance, and surface pattern improved agreement with clinicians. Inter-clinician agreement was low, confirming the intrinsic subjectivity of wound edge classification. Geometry-based analysis identified coherent edge-profile patterns but showed poor correspondence with clinical annotations. In contrast, a supervised classifier incorporating both geometric and visual features achieved agreement comparable to, and in some comparisons higher than, the agreement observed among clinicians. Clinical wound edge assessment is not driven by edge geometry alone. Visual cues such as wound shape, colour appearance, and surface pattern appear to influence expert classification and may contribute to variability. Automated image-based analysis may support more reproducible wound edge assessment, provided that it is externally validated in diverse clinical settings.