Calculators | Wound Care Evidence-Based Guide

SINBAD Calculator (Diabetic Foot Ulcer)

Six items scored 0–1 each, total 0–6. Used for communication, audit, and prognostic stratification (the basic classification recommended by IWGDF 2023).

S — Site

Forefoot (0 points) Midfoot / hindfoot (1 point)

I — Ischemia

Pedal blood flow intact, at least one palpable pulse (0 points) Clinical evidence of ischemia (1 point)

N — Neuropathy

Protective sensation intact (0 points) Protective sensation lost (1 point)

B — Bacterial infection

No infection (0 points) Infection present (1 point)

A — Area

< 1 cm² (0 points) ≥ 1 cm² (1 point)

D — Depth

Confined to skin / subcutaneous tissue (0 points) Reaching muscle / tendon / bone (1 point)

Source: Monteiro-Soares M, et al. IWGDF 2023 classification update. DOI:10.1002/dmrr.3648

WIfI Calculator (SVS Threatened Limb Classification)

Wound / Ischemia / foot Infection each graded 0–3 → estimates the 1-year amputation-risk stage and benefit of revascularization (SVS 2014).

W — Wound

0: No ulcer, no gangrene 1: Small, shallow ulcer, no gangrene 2: Deep ulcer with exposed bone/joint/tendon ± gangrene limited to toes 3: Extensive deep ulcer or gangrene extending to forefoot/midfoot

I — Ischemia (ABI / toe pressure / TcPO₂, whichever available)

0: ABI ≥ 0.80 (toe pressure/TcPO₂ ≥ 60 mmHg) 1: ABI 0.60–0.79 (40–59 mmHg) 2: ABI 0.40–0.59 (30–39 mmHg) 3: ABI < 0.40 (< 30 mmHg)

fI — foot Infection (IWGDF/IDSA correspondence)

0: No infection 1: Mild (skin/subcutaneous only, erythema ≤ 2 cm) 2: Moderate (erythema > 2 cm or deep structures) 3: Severe (with systemic inflammatory response, SIRS)

Source: Mills JL Sr, et al. SVS WIfI. J Vasc Surg. 2014;59(1):220–234. DOI:10.1016/j.jvs.2013.08.003 (stage lookup summarized from Table 6 of the original article)

University of Texas (UT) Classifier (Diabetic Foot Ulcer)

A 4×4 matrix of depth Grade 0–3 × infection/ischemia Stage A–D (1996). Deeper wounds with infection/ischemia carry higher amputation risk. See Staging & Records, section 4.

Grade — depth (0–3)

Grade 0: pre- or post-ulcerative lesion (intact skin) Grade 1: superficial wound not involving tendon, capsule, or bone Grade 2: penetrating to tendon or joint capsule Grade 3: penetrating to bone or joint

Stage — infection and ischemia (A–D)

Stage A: no infection or ischemia Stage B: with infection Stage C: with ischemia Stage D: with both infection and ischemia

Source: Lavery LA, Armstrong DG, Harkless LB. 1996 (DOI:10.1016/s1067-2516(96)80125-6); Armstrong DG, et al. Diabetes Care 1998;21(5):855–859 (DOI:10.2337/diacare.21.5.855) (validation study: depth and infection/ischemia each increase amputation risk)

WIfI / SINBAD / UT Calculators

SINBAD Calculator (Diabetic Foot Ulcer)

WIfI Calculator (SVS Threatened Limb Classification)

University of Texas (UT) Classifier (Diabetic Foot Ulcer)