Roughly half of all people who develop a diabetes-related foot ulcer also have peripheral artery disease (PAD), and its presence changes almost everything about how that ulcer behaves. Wounds that would otherwise close in weeks stall for months, infections spread further before they are contained, and the risk of major amputation and cardiovascular death rises sharply. The 2023 intersocietal guidelines produced jointly by the International Working Group on the Diabetic Foot (IWGDF), the European Society for Vascular Surgery (ESVS) and the Society for Vascular Surgery (SVS) — the first unified document from these three bodies — describe PAD as a principal driver of the global amputation burden in diabetes (Fitridge et al., 2023).
Why Arterial Disease Is Harder to Detect in Diabetes
PAD in diabetes is not simply PAD that happens to occur in a diabetic patient. The disease tends to be distal, affecting the tibial and pedal vessels below the knee rather than the larger inflow arteries, and it is frequently accompanied by medial arterial calcification, which stiffens the vessel wall. Peripheral neuropathy compounds the problem: the classic warning symptom of claudication or rest pain may simply never be felt, so an ulcer can be the first sign of significant ischaemia.
Calcified, non-compressible arteries also distort the most widely used bedside test. A systematic review of 40 diagnostic accuracy studies conducted for the 2023 guidelines found that an ankle-brachial index (ABI) below 0.9 raises the likelihood of PAD, but an ABI in the normal range does not reliably exclude it (Chuter et al., 2024). The authors reported positive likelihood ratios ranging from 1.69 to 19.9 and negative likelihood ratios from 0.29 to 0.84 — a wide spread that reflects how unevenly the test performs in this population.
What the Evidence Supports at the Bedside
The same review found that a toe-brachial index below 0.70 has moderate ability to rule PAD in and out, and that monophasic pedal Doppler waveforms are associated with disease while triphasic or biphasic waveforms make it less likely. Inter-rater reliability was poor for pulse palpation alone, and no single bedside test or combination emerged as definitively superior. The practical conclusion drawn in the guidelines is that a normal-looking bedside result in a person with a non-healing ulcer should not close the question — further vascular imaging is warranted when a wound fails to progress, regardless of what the ABI showed.
Estimating Healing and Amputation Risk
Once PAD is identified, the next question is what it means for this particular limb. The IWGDF 2023 classification guideline recommends the WIfI system — which grades Wound extent, Ischaemia and foot Infection separately — as a means of stratifying healing likelihood and amputation risk in people with PAD (Monteiro-Soares et al., 2024). The same document recommends the simpler SINBAD system for routine communication between clinicians and for auditing population outcomes, and notes that the certainty of the underlying evidence for all these systems was judged, at best, as low. Notably, the guideline stopped short of endorsing any existing system for predicting the outcome of an individual ulcer — a reminder that these tools stratify risk rather than forecast a specific patient’s course.
Revascularization: What the Randomized Trials Showed
When a wound will not heal because perfusion is inadequate, restoring blood flow becomes the central intervention. Two large randomized trials published within months of each other have shaped current thinking about how.
BEST-CLI randomized patients with chronic limb-threatening ischaemia to open surgical bypass or endovascular therapy. Among participants who had an adequate great saphenous vein available as a conduit, surgical bypass produced significantly fewer major adverse limb events or deaths than endovascular treatment. Among those without a suitable vein, the two strategies performed similarly (Farber et al., 2022).
BASIL-2 examined a narrower group — patients requiring infrapopliteal revascularization — and reached a different conclusion. Major amputation or death occurred in 63% of the vein bypass group versus 53% of the best endovascular treatment group (adjusted hazard ratio 1.35, 95% CI 1.02–1.80), a difference driven largely by fewer deaths in the endovascular arm (Bradbury et al., 2023).
The trials are complementary rather than contradictory: they enrolled different anatomical populations. Together they argue against a single default strategy and in favour of individualized decisions based on the pattern of disease, conduit availability and the patient’s overall condition.
The Cardiovascular Context
PAD in a person with a foot ulcer is rarely an isolated finding. It signals systemic atherosclerosis; the risk of myocardial infarction, stroke and cardiovascular death in this group is substantial. Both the intersocietal guidelines and the Australian adaptation of the IWGDF recommendations emphasize that intensive cardiovascular risk management should accompany any limb-directed treatment, and that centres treating diabetes-related foot ulcers need either in-house expertise or rapid access to services capable of diagnosing and treating PAD (Chuter et al., 2022).
Key Points
Approximately half of diabetes-related foot ulcers occur in limbs with peripheral artery disease, and neuropathy and arterial calcification make that disease easy to miss. A normal ankle-brachial index does not exclude PAD; a non-healing ulcer justifies further vascular assessment on its own. The WIfI system helps stratify healing and amputation risk, though no classification reliably predicts an individual outcome. When revascularization is needed, the choice between open bypass and endovascular treatment depends on anatomy and conduit availability. In every case, the ischaemic diabetic foot is a marker of systemic vascular disease requiring attention beyond the limb itself.
References
- Fitridge R, Chuter V, Mills J, et al. Editor’s Choice — The Intersocietal IWGDF, ESVS, SVS Guidelines on Peripheral Artery Disease in People With Diabetes Mellitus and a Foot Ulcer. European Journal of Vascular and Endovascular Surgery. 2023;66(4):454–483.
- Chuter V, Schaper N, Mills J, et al. Effectiveness of bedside investigations to diagnose peripheral artery disease among people with diabetes mellitus: A systematic review. Diabetes/Metabolism Research and Reviews. 2024;40(3):e3683.
- Monteiro-Soares M, Hamilton EJ, Russell DA, et al. Guidelines on the classification of foot ulcers in people with diabetes (IWGDF 2023 update). Diabetes/Metabolism Research and Reviews. 2024;40(3):e3648.
- Farber A, Menard MT, Conte MS, et al. Surgery or Endovascular Therapy for Chronic Limb-Threatening Ischemia. New England Journal of Medicine. 2022;387(25):2305–2316.
- Bradbury AW, Moakes CA, Popplewell M, et al. A vein bypass first versus a best endovascular treatment first revascularisation strategy for patients with chronic limb threatening ischaemia who required an infra-popliteal, with or without an additional more proximal infra-inguinal revascularisation procedure to restore limb perfusion (BASIL-2): an open-label, randomised, multicentre, phase 3 trial. The Lancet. 2023;401(10390):1798–1809.
- Chuter V, Quigley F, Tosenovsky P, et al. Australian guideline on diagnosis and management of peripheral artery disease: part of the 2021 Australian evidence-based guidelines for diabetes-related foot disease. Journal of Foot and Ankle Research. 2022;15(1):51.
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