Guide — Wound Care
Diabetic Foot Ulcers
Diabetic foot ulcers (DFUs) are a leading cause of hospitalization, amputation, and mortality in patients with diabetes. They result from the convergence of peripheral neuropathy, vascular disease, and impaired immunity — all driven by chronic hyperglycemia.
11 min read · Wound Care
Educational use only. Diabetic foot ulcer management requires an interprofessional team including wound care specialists, podiatry, vascular surgery, endocrinology, and infectious disease when appropriate. This guide provides foundational clinical education. This material supports nursing education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional policy, or medical direction. Always follow facility protocols and current provider orders.
Epidemiology
15–25%
Lifetime DFU risk in diabetics
>50%
Of lower-extremity amputations linked to diabetes
5 years
5-year mortality after major amputation (~50%)
#1
Preventable cause of diabetes-related hospitalization
Pathophysiology
DFUs arise from the combination of three primary mechanisms — all worsened by sustained hyperglycemia:
Peripheral Neuropathy (most common driver)
- Sensory: loss of protective sensation — patient cannot feel injury, pressure, or temperature; wounds develop without pain
- Motor: intrinsic muscle weakness → foot deformities (claw toes, hammertoes, Charcot foot) → altered pressure distribution → callus and ulceration at bony prominences
- Autonomic: decreased sweating → dry, cracked skin; arteriovenous shunting → increased bone blood flow contributing to Charcot arthropathy
Peripheral Arterial Disease (PAD)
- Atherosclerosis of tibial and peroneal arteries → reduced perfusion to foot
- Impaired oxygen, nutrient delivery, and immune cell recruitment to wound
- Severely limits healing capacity — even small wounds may not heal
- Present in ~50% of DFU patients; associated with limb-threatening ischemia
Impaired Immunity
- Hyperglycemia impairs neutrophil and macrophage function
- Reduced bacterial killing capacity → rapid progression to deep infection
- Increased risk of osteomyelitis — bone infection present in up to 20% of DFUs at presentation
Wagner Classification System
| Grade | Description | Management Implication |
|---|---|---|
| 0 | Intact skin — high-risk foot: callus, deformity, neuropathy, or PAD present but no open wound | Prevention, education, footwear, podiatry referral |
| 1 | Superficial ulcer involving epidermis and/or dermis — does not penetrate to tendon, capsule, or bone | Offloading, wound care, glucose control, follow-up in 1 week |
| 2 | Full-thickness ulcer extending to tendon, ligament, joint capsule, or bone | More aggressive wound care, possible debridement, infectious disease, vascular assessment |
| 3 | Deep ulcer with abscess, osteomyelitis, or septic arthritis | Hospitalization, IV antibiotics, surgical debridement, imaging (MRI for osteomyelitis) |
| 4 | Gangrene of forefoot (partial foot) | Vascular surgery, possible partial amputation or revascularization |
| 5 | Extensive gangrene of entire foot | Major amputation likely required |
Risk Factors
High-Risk Foot Characteristics
- Loss of protective sensation (monofilament test failure)
- Peripheral arterial disease (ABI <0.9)
- Previous foot ulceration or amputation
- Foot deformity: Charcot foot, claw toes, hammertoes, prominent metatarsal heads
- End-stage renal disease (dialysis)
- Callus or plantar callus over bony prominences
- Limited joint mobility (rigid plantar flexion)
Systemic and Behavioral Risk Factors
- HbA1c >8.0% — poor glycemic control accelerates neuropathy and PAD
- Diabetes duration >10 years
- Obesity — increased plantar pressure
- Smoking — accelerates PAD and impairs wound healing
- Barefoot walking — removes protective footwear barrier
- Visual impairment — cannot inspect feet
- Social isolation — reduced access to care and monitoring
Assessment
Vascular Assessment
- Ankle-Brachial Index (ABI): ABI <0.9 = PAD; ABI <0.4 = severe ischemia; ABI >1.3 = calcified (non-compressible) vessels — unreliable, requires toe pressure
- Pedal pulses: dorsalis pedis and posterior tibial — assess quality bilaterally
- Skin temperature: cold foot may indicate ischemia
- Capillary refill >2 seconds at toe: impaired perfusion
- Dependent rubor: foot turns red when dependent — severe PAD
Neurological Assessment
- 10-g monofilament test (Semmes-Weinstein): apply to plantar surface at 10 sites; inability to feel monofilament = loss of protective sensation (LOPS)
- Vibration sense: 128 Hz tuning fork at great toe
- Temperature discrimination: warm vs. cool
- Sharp vs. dull sensation
Wound Assessment
- Location (plantar surface over metatarsal heads, heel, between toes most common)
- Size: length × width × depth; probe-to-bone test (positive = suspect osteomyelitis)
- Wound bed tissue, drainage, odor
- Callus formation surrounding wound
- Signs of infection: erythema, warmth, swelling, purulence, systemic signs
Prevention
Most DFUs are preventable — nursing education is the cornerstone of prevention
Daily Foot Care Habits
- Inspect both feet daily — use a mirror for plantar surface if vision is limited; enlist help if needed
- Wash feet daily in lukewarm water (test temperature with elbow — neuropathy prevents accurate temperature sensing)
- Dry thoroughly between toes — moisture → fungal infection, maceration
- Moisturize dorsum and plantar surface — NOT between toes (excess moisture promotes infection)
- Trim nails straight across, file edges; do not cut corners
- Never walk barefoot — at home or outdoors
Footwear and Podiatry
- Properly fitting, protective footwear — broad toe box, cushioned sole, no internal seams
- Therapeutic/diabetic shoes with custom insoles to redistribute plantar pressure
- Inspect inside shoes before putting on — foreign objects, rough areas
- Regular podiatry visits for callus debridement and nail care
- Glycemic control: HbA1c target per endocrinology — lower HbA1c significantly reduces neuropathy progression
- Smoking cessation — most modifiable vascular risk factor
Treatment Overview
Offloading
The most critical intervention for plantar DFUs. Reduces pressure on the wound and allows healing. Options: Total Contact Cast (TCC) — gold standard for pressure redistribution; removable cast walkers (RCW/CAM boot) — less effective than TCC (compliance-dependent); therapeutic footwear, wheelchairs, crutches. Offloading is required for all plantar neuropathic ulcers.
Wound Care
Moist wound healing environment; frequent debridement of callus and nonviable tissue (especially in neuropathic ulcers — sharp debridement at each visit promotes healing); select dressing based on wound characteristics; advanced therapies for nonhealing wounds: negative pressure wound therapy (NPWT/VAC), growth factor preparations (becaplermin/Regranex), skin substitutes, hyperbaric oxygen therapy.
Infection Management
Prompt antibiotic therapy for infected ulcers. Superficial infection: oral antibiotics targeting gram-positive organisms. Deep/limb-threatening infection: broad-spectrum IV antibiotics; surgical debridement. Osteomyelitis (suspect if probe-to-bone positive, bone visible, Wagner Grade 3+): MRI most sensitive; bone biopsy for culture; 4–6 weeks of targeted antibiotic therapy; surgical resection may be required.
Vascular Intervention
Revascularization (endovascular or surgical bypass) for DFUs with significant PAD — required when ABI <0.4 or wound fails to progress despite optimal local care. Referral to vascular surgery when ischemic component identified.
Glucose Control
Hyperglycemia impairs every stage of wound healing. Target glucose 100–180 mg/dL in most hospitalized non-critically ill patients; 140–180 mg/dL in the critically ill/ICU (ADA). HbA1c target per endocrinology for outpatients. Insulin adjustments may be needed during wound care phase.
Patient Education
Use teach-back to verify understanding of all education points. Involve family or caregiver in education when the patient has visual impairment or mobility limitations.
- Inspect feet daily — every single day; report any new wound, redness, warmth, or swelling immediately
- Never self-treat foot problems with over-the-counter corn pads, callus shavers, or chemicals — these are dangerous with neuropathy
- Always wear shoes — even inside the house
- Report early warning signs: new blisters, callus buildup, change in skin temperature or color, any break in skin integrity
- Glucose control is wound care — high blood sugar prevents healing
- Smoking cessation: provide resources and referrals
- Do not soak feet — increases maceration risk
- Attend all podiatry and wound care appointments — do not skip
NCLEX Pearls
- ✦Diabetic foot ulcers = neuropathy + vasculopathy + impaired immunity. Loss of protective sensation means patients cannot feel injury — wounds often go unnoticed.
- ✦Priority for plantar DFU: OFFLOADING. No amount of wound care will heal a plantar ulcer if the patient continues to walk on it without pressure redistribution.
- ✦Positive probe-to-bone test: insert sterile probe into wound — if it contacts hard material (bone) without intervening tissue, suspect osteomyelitis.
- ✦Monofilament test (10-g Semmes-Weinstein): inability to feel monofilament = loss of protective sensation = HIGH RISK for DFU.
- ✦ABI <0.9 = peripheral arterial disease; ABI >1.3 = calcified vessels (unreliable result in diabetics) — use toe pressures instead.
- ✦DFU patient education priorities: daily foot inspection, protective footwear always, glucose control, early reporting of any foot change, no self-treatment of foot problems.
- ✦Osteomyelitis treatment: 4–6 weeks of antibiotics based on bone culture; surgical debridement if conservative treatment fails.
Related Resources
Standards & sources
Fact-checked Jun 21, 2026This page is written to align with NPUAP / EPUAP / PPPIA (pressure injury staging) · Wound, Ostomy and Continence Nurses Society (WOCN). It is an educational summary, not a citation of any single document — always verify specific doses, values, and protocols against current guidelines and your facility policy. How we source content →