Multiple Tunnels Technique for Limb Salvage in Complex Diabetic Foot Infection: A Prospective Single-Center Study.

BACKGROUND: Diabetic foot infection (DFI) remains a major cause of hospitalization, repeated surgical procedures, and lower-extremity amputation. Conventional debridement may not adequately address multi-compartment infection and can result in unnecessary loss of viable tissue. OBJECTIVE: To evaluate the safety and effectiveness of the Multiple Tunnels Technique for infection control and limb salvage in patients with complex DFIs. METHODS: This prospective observational study included 236 patients with complex DFIs treated in the vascular surgery department at Kafrelsheikh university hospital between December 2022 and December 2025. The technique involved creation of interconnected subcutaneous tunnels along suspected pathways of infection spread to improve drainage and infection control while preserving viable tissue. Primary outcomes included infection control, reintervention, amputation, wound healing, and limb salvage. RESULTS: Successful infection control after the primary procedure was achieved in 226 patients (95.8%). Mean wound healing time was 6.7 ± 2.1 weeks. Additional major debridement was required in 8 patients (3.4%), while 10 patients (4.2%) underwent secondary minor procedures. Toe or forefoot amputations were required in 128 patients (54.2%), and Chopart amputation was performed in 3 patients (1.3%) with Wagner grade 5 infection. No below-knee or above-knee amputations or mortality were observed. Overall above-ankle limb salvage rate was 100%. CONCLUSIONS: The Multiple Tunnels Technique appears to be a reproducible limb salvage approach for complex DFIs. By improving drainage while preserving viable tissue, the technique may reduce reintervention and major amputation rates in selected patients.