Multimodal therapy as an algorithm to limb salvage in diabetic patients with large heel ulcers

Abstract

In many series of diabetic foot ulcer care, heel ulcers greater than 4 cm across have been identified as an independent predictor of limb loss. Therefore, we set out to pursue the most aggressive limb salvage algorithm in patients with heel ulcers greater than 4 cm in diameter. Over 5 years, we identified 21 patients, 39-84 years of age, all with diabetes mellitus, with heel ulcers greater than 4 cm in diameter and had magnetic resonance imaging or bone scan evidence of osteomyelitis. Seven of the 21 patients had end-stage renal disease defined as being haemodialysis dependent. All patients had ankle brachial indices <0·4 or monophasic pulse volume recordings. All patients underwent distal bypass surgery with vein. After adequate perfusion was obtained, all patients underwent partial calcanectomy and intra-operative negative pressure wound therapy (NPWT) placement. This was followed by treatment with recombinant platelet-derived growth factor (PDGF). One patient underwent amputation during the healing process secondary to ongoing sepsis. Twenty of 21 patients healed acutely (within 6 months). Three of 20 patients went on to subsequent below knee amputation within 12 months of healing primarily. At 2 years, 12 of 21 (57%) were ambulating independently, 1 of 21 was dead, 4 of 21 had undergone amputation, 4 (19%) had limbs that were intact but were not ambulating. A total limb salvage rate of 76% at 2 years mirrored the secondary patency rates, with 100% follow up. Heel ulcers require multimodality therapy if they are going to have any chance to heal. We believe the algorithm presented allows for the required revascularisation and a modulation of the heel ulcer microenvironment by augmenting the microcirculation through NPWT, and improving the proliferative capacity with PDGF.