Diabetic Foot Ulcers: Risks, Signs and the Importance of Proper Care

In Canada, over 4 million people were affected by Type 1 and Type 2 diabetes in 2023, a figure expected to increase by 26 per cent by 2033.^[1] Diabetic Foot Ulcers (DFU) are among the most serious complications of diabetes and without proper management, or if left untreated, they can lead to severe consequences like infections and even amputation.

In this Ask the Expert, we spoke to Deanna Lundstrom BScN, a Sales Specialist in Medline Canada’s Skin Care and Advanced Wound Management portfolio, to explore the causes of DFUs, best practices for prevention, treatment, and overall effective wound care.

Q: What is a DFU and what causes them?

DFUs most commonly develop on the ball of the foot or the underside of the big toe but can also appear on the top and bottom of any toe.

The main causes are elevated blood sugar levels, lack of foot care, decreased blood flow to the feet, and neuropathy (lack of any sensation). In diabetes, the body either does not produce enough insulin or cannot effectively use it, leading to consistently high blood sugar levels. If blood sugar levels remain elevated, the arteries and veins can suffer damage, leading to the formation of DFUs. Poor foot care—such as neglecting early warning signs or wearing shoes that are too tight—can further contribute to their development. Neuropathy is particularly dangerous, as the loss of sensation can prevent a person from noticing minor injuries, like blisters or calluses, which can rapidly progress into severe wounds.

Q: What are the warning signs for DFU and why is a blister considered an indicator?

Swelling, warmth or redness in the feet and/or lower legs can all be warning signs of DFUs. Some may also experience blood or discharge in socks or calluses on the feet. Other symptoms may also include numbness, tingling, pins and needles or itching sensation, tightness, heaviness, pain, or cramps in your feet or legs. If there is a blister or sore on the feet this requires immediate attention.

Without treatment, a small blister on the foot can become an open wound in a matter of hours or days. People with diabetes often have nerve damage called peripheral neuropathy, which prevents them from feeling pain. Any type of blister, cut or scrape may therefore go unnoticed and possibly lead to a larger wound that could get infected.

Q: What is meant by the term “offloading” and how does one know they are “offloading” properly? Why should people with diabetes offload?

Offloading involves relieving pressure to aid in healing. There are several products that are considered offloading devices that include total contact casts, removeable casts and specialized shoes that relieve pressure on the foot to help support healing.

People with diabetes need to offload as they are at a greater risk for loss of sensation due to nerve damage. Offloading is the gold standard to help a DFU heal and prevent potential amputations.

Q: How long does it take a DFU to heal?

There are many factors and not all wounds will heal in the same amount of time. The one key factor is blood flow. If there is less blood flow to the feet, the injured tissue will not get oxygen and nutrients which are the factors required for the DFU to heal. Other factors that contribute to healing include blood sugar control, offloading and smoking cessation.

Q: Is a DFU the same as a pressure injury on the foot?

No, a DFU is a wound that occurred in a person with diabetes because of a blister or a sore on the foot that may have gone unnoticed due to lack of sensation.

A pressure injury is an injury caused by the pressure of a bone against a surface for an extended period of time without relief from the pressure. One thing that is the same is the need to offload.

Q: What are some best practices you recommend for DFUs?

• Be sure to check blood glucose regularly.
• Make it a habit to check your feet daily. Inspect for any cuts, blisters, redness, new swelling, or nail problems. 
• Keep your feet warm and dry. Consider wearing socks to bed and dry your feet well between your toes after bathing. Also make sure to moisturize your feet — but not between your toes — because this could promote a fungal infection.
• Wear properly fitting shoes and socks and remember to shake out your shoes before wearing them to avoid accidental injury due to something in your shoes that you can’t feel.

Q: How can Medline support clinicians in the prevention of DFU’s?

The Advanced Wound Management Portfolio includes a wide variety of evidenced-based products that will promote wound healing.

Medline offers a comprehensive skin and wound care portfolio with a variety of cleansers, moisturizers, and barriers for prevention. These products are botanical based and free from ingredients that can be sensitizing. It is important to provide a cleanser that is pH balanced and gentle to the skin. It is also important to provide moisturization to the feet and lower legs, as dry skin is at greater risk of breakdown and infection in people with diabetes. There should be no moisturizer added between the toes.

To learn more about Medline’s Advanced Wound Care offerings, please visit medline.ca/en/advanced-wound-care or speak to your Medline Clinical Support Clinician.

[1] Diabetes in Canada: Backgrounder. Ottawa: Diabetes Canada; 2023.