Smart Dressings for Pre-Ulcer Risk Surveillance and Closed-Loop Chronic Wound Management: Advances, Discrepancies, and Translational Horizons.

Chronic ulcers, including diabetic foot ulcers, pressure ulcers, and venous leg ulcers, remain a major clinical challenge due to their progressive tissue deterioration and high recurrence rates. Current preventive strategies largely rely on intermittent assessment and often fail to detect early pathological changes before visible tissue damage occurs. Recent advances in flexible electronics and wearable biointerfaces have enabled smart dressings capable of continuous physiological surveillance. However, existing studies and reviews mainly focus on individual sensing technologies, while lacking an integrated framework for predictive ulcer prevention. Here, we systematically review the emerging transition from reactive wound monitoring toward predictive, closed-loop bioelectronic prevention systems. We summarize recent progress in smart dressings from four interconnected aspects: pre-ulcer biological transition, multimodal physiological sensing, AI-assisted data integration and risk prediction, and closed-loop preventive intervention. Particular emphasis is placed on the role of temporal physiological trajectories and multimodal signal fusion in identifying occult tissue deterioration prior to overt ulcer formation. We further discuss key translational challenges, particularly highlighting that the current evidence base predominantly relies on benchtop and preclinical animal models, while prospective clinical validation demonstrating measurable reductions in ulcer incidence remains largely absent. Finally, emerging opportunities in self-powered systems, edge AI, and autonomous therapeutic platforms are highlighted for next-generation ulcer prevention. This review is based on a structured search of PubMed, Web of Science, and IEEE Xplore (2015-2026) focusing on flexible bioelectronics, multimodal physiological sensing, AI-assisted prediction, and closed-loop preventive intervention. Throughout, we distinguish three prevention scenarios: primary prevention on intact high-risk skin, prevention of recurrence on healed skin, and prevention of deterioration in existing wounds. We emphasize that most supporting studies remain device-level, animal-based, or short-term feasibility investigations, and that prospective clinical validation of reduced ulcer incidence is still lacking.