What Are Diabetic Foot Ulcers?

A diabetic foot ulcer is an open sore or wound that typically forms on the bottom of the foot in people with diabetes. It’s a serious complication that, if left untreated, can lead to infection, hospitalization—or even amputation.

The best way to prevent these outcomes? Know the warning signs early by understanding the diabetic foot ulcer stages and how they progress.

Diabetic Foot Ulcer Stages Explained

Healthcare professionals often refer to wound stages to describe how severe an ulcer is. While multiple classification systems exist (like the Wagner or University of Texas systems), they all help providers decide the best course of treatment.

Here’s a simplified breakdown of the main stages of a diabetic foot ulcer:

Stage 0 – At Risk but No Ulcer

What it means: The skin is intact, but the foot shows signs of high risk: deformities, calluses, poor circulation, or previous ulcers.
What to do: Preventive care is key. Foot checks, proper footwear, and glucose control are essential.

Stage 1 – Superficial Ulcer

What it means: An open sore forms, but only the top layers of the skin are affected.
Symptoms: Redness, minor drainage, or pain.
Treatment: Cleaning, dressing, offloading pressure (e.g., using special shoes or walking aids).

Stage 2 – Deeper Ulcer Extending to Tendon or Bone

What it means: The ulcer now penetrates deeper, potentially reaching tendons or joints.
Risks: Higher chance of infection and longer healing time.
Treatment: May require antibiotics, minor surgery, or more intensive wound care.

Stage 3 – Infection and Tissue Damage

What it means: The ulcer is now infected. There may be tissue death (necrosis), abscesses, or foul odor.
Warning signs: Swelling, fever, drainage, and severe pain.
Treatment: Hospitalization, IV antibiotics, surgical cleaning, and sometimes bone scans.

Stage 4 – Partial Foot Gangrene

What it means: Dead tissue affects part of the foot, often the toes or forefoot.
Outcome: Tissue may turn black, dry, and numb.
Treatment: Surgery is often required to remove dead tissue and prevent further spread.

Stage 5 – Full Foot Gangrene

What it means: Severe tissue death may spread throughout the foot.
Urgency: A medical emergency.
Treatment: Amputation is often the only option to protect the patient's overall health.

Why Early Detection Matters

Many diabetic foot ulcers are preventable with early detection and proactive care. Monitoring foot health daily, especially for those with neuropathy or circulation issues, can stop a Stage 0 or Stage 1 ulcer from progressing to a life-altering Stage 4 or 5.

How to Protect Your Feet

Inspect feet daily for blisters, redness, or cuts
Keep blood sugar levels in target range
Wear proper footwear — avoid going barefoot
Never ignore pain or swelling
See a healthcare provider immediately for any foot concerns

Looking to Take Part in a Diabetic Foot Ulcer Study?

At Alliance Research Institute, we’re conducting studies to explore new treatments for diabetic foot ulcers at different stages. If you or someone you love is affected, learn how you may qualify for a clinical trial.

Visit our website to learn more

Conclusion

Diabetic foot ulcers are a serious complication, but knowing the stages of diabetic foot ulcers can make a life-changing difference. Early detection and proper treatment can stop ulcers from progressing and help prevent long-term damage—including infections or amputation.

If you or someone you care about is living with diabetes, make foot care a daily priority. And remember, the earlier you act, the better the outcome.

Understanding Diabetic Foot Ulcer Stages: What You Need to Know