Early Digital and Inflammatory Markers of Delayed Healing in Burns, Ulcers, and Hand Reconstruction: A Prospective...

Delayed healing is assessed differently in burns, chronic ulcers, and hand soft-tissue reconstruction wounds, yet these patients are often managed in the same wound service. This prospective single-center cohort study evaluated whether standardized digital wound features, thermography, and local inflammatory markers added to early delayed-healing risk assessment across these three categories. Adults enrolled between 1 January 2024 and 31 December 2025 underwent baseline wound photography, thermal imaging, and wound-fluid sampling. Delayed healing was defined using prespecified wound-type-specific criteria. Clinical, digital-feature, inflammatory-marker, baseline combined, and day-7 updated models were fitted with wound type forced into each model and internally validated with 1000 bootstrap samples. Of 168 patients (57 with burns, 70 with chronic ulcers, and 41 with hand soft-tissue reconstruction wounds), 59 (35.1%) met delayed-healing criteria. Delayed-healing wounds were deeper and had more slough and necrotic tissue, higher exudate scores and wound-reference temperature differences, and higher interleukin-6 (IL-6) concentrations; several other differences were imprecise. Apparent AUCs were 0.691 for the clinical model, 0.717 for the baseline combined model, and 0.715 for the early updated model. The corresponding optimism-corrected AUCs were 0.632, 0.660, and 0.649. The baseline combined model did not significantly improve discrimination over the clinical model (ΔAUC 0.026; DeLong p = 0.400), and adding day-7 area reduction did not improve the baseline combined model (ΔAUC -0.002; p = 0.662). These models therefore showed modest internally validated performance rather than clinical readiness. At present, they serve primarily as a hypothesis-generating framework for early risk stratification. Independent external validation and prospective impact assessment are required before implementation.