Management of the diabetic foot

Diabetic foot disease is one of the most feared complications of diabetes. In Ireland, a person with diabetes is 22 times more likely to undergo a non-traumatic lower limb amputation than a person without diabetes. Ulceration and limb loss represent a huge burden on the individual, their family, the health service and social care as a whole. 

Epidemiology

There are approximately 266,000 people living with diabetes in Ireland. We have no national diabetes register and this data is taken from the Scottish Diabetes Register and adjusted for the Irish population (2021).¹ The annual risk of developing a diabetic foot ulcer is 2-3%, with a lifetime risk of 15%. Mortality rates associated with the development of foot ulcers are estimated to be 5% in the first year, while five-year mortality could be as high as 42%.²

Lower limb amputation is a feared complication of diabetes. The current rate is 145 to 176 per 100,000 people with diabetes per year.³ Risk increases with reduced pedal sensation and pulses. Amputation can be prevented by early screening for risk factors for diabetic foot ulcer and education on good foot care. 

Economic cost

A study in St James’s Hospital, Dublin in 2004 looked at admissions with diabetic foot ulcers (DFU) as the primary complaint. The admissions lasted on average 20 days, with eight of the admitted 30 patients requiring amputation. The average estimated cost of managing a diabetic foot ulcer in this study was greater than €23,000, and this was 20 years ago. This highlights the economic burden of foot ulcers as a complication of diabetes.⁴

Prevention – Model of care for the diabetic foot, HSE 2022

Care pathways

• Self-management of foot care: The patient has an understanding of their foot risk status. They receive ongoing education in diabetic footcare from the healthcare practitioner leading their footcare. They perform regular foot inspection and implement appropriate self-management strategies. The patient is aware of the contact details for the appropriate service they need to access

• Type 1 diabetes: These patients with be reviewed by their endocrinology team. They will have their feet assessed and risk stratified. Their care will be managed by their medical team, the foot protection team and multidisciplinary foot protection team as appropriate

• Type 2 diabetes: At diagnosis of type 2 diabetes, a person will have their initial foot screening and risk classification in general practice. If the patient is at low risk of ulceration they will have an annual review in general practice. A moderate risk of diabetic foot ulcer will trigger a review by the foot protection team (FPT) once a year. High risk of foot ulceration or in remission will lead to a six-monthly review with the FPT. Active foot disease will be referred, treated and managed by the multidisciplinary foot team. There are clear pathways of referral to this team and it will see the patient within 24 hours. If there are signs of sepsis then the patient should be referred immediately to the ED with a notification to the multidisciplinary team as a matter of urgency.

Foot exam

Latest American Diabetes Association (ADA) guidelines (https://diabetesjournals.org/clinical/article/41/1/4/148029/Standards-of-Care-in-Diabetes-2023-Abridged-for) recommend annual foot screening for asymptomatic risk factors for diabetic foot ulcer (ADA guidelines 2023 rec 12.21). Obtain a prior history of ulceration or amputation, Charcot foot, angioplasty or vascular surgery, cigarette smoking, retinopathy, renal disease and assess for current symptoms of neuropathy (pain, burning, numbness) and vascular disease (claudication, leg fatigue).

The examination should include inspection of the skin, assessment of foot deformities, neurological assessment (10g monofilament testing with at least one other assessment: pinprick, temperature, vibration) and vascular assessment including pulses in the legs and feet (ADA). If a patient has evidence of sensory loss or prior ulceration or amputation, they should have their feet inspected at every visit. 

CDM programme

The Chronic Disease Management (CDM) programme allows for biannual review of patients with type 2 diabetes in Ireland who have a GMS/doctor visit card. Included in the CDM review of patients with type 2 diabetes is a foot screen covering the main findings of neuropathy, vasculature and deformity. It allows the GP/general practice nurse to spend some time discussing good foot care including regular inspection with a mirror, good skin care and appropriate footwear. 

There are booklets to give to the patient to assist them in learning about good foot care and appropriate footwear. As detailed above, if the foot exam is normal, annual review is sufficient. Regular review of diabetes allows for improved glycaemic control, blood pressure control, lipid management and crucially, smoking cessation.

We know that a basic tenet of medicine is that prevention is better than cure and nowhere is that more appropriate than in the area of foot care in diabetes. We know these patients are at high risk and in the community, we have the opportunity to examine and educate to prevent burdensome and expensive complications.

How does the ulcer develop?

An ulcer develops due to a combination of loss of sensation due to peripheral neuropathy, reduced circulation and altered mechanics which result in a callus or a wound developing that is unnoticed by the patient. Peripheral neuropathy and loss of sensation are the key drivers. 

Ulcers usually occur in areas of the foot that sustain regular pressure, friction or trauma, often on the sole of the foot. Autonomic neuropathy in diabetes can also cause excessively dry skin, leading to faster callus formation. A callus can break down and form an ulcer which then becomes infected. Wound-healing is delayed due to poor arterial supply and high circulating glucose levels can be a nidus for rapid infection. 

If a patient with diabetes doesn’t regularly inspect their feet with a mirror, the wound can progress unnoticed. Unchecked, the ulcer can lead to osteomyelitis, sepsis, amputation or even death.

Good foot care

It is imperative that people with diabetes engage in regular footcare. It is our job as healthcare professionals to inspect feet at least once a year, but more importantly, to educate patients on the importance that they regularly check their own feet. 

We recommend patients with at-risk feet to check their feet daily. Patients should sit comfortably, remove socks, shoes and roll up trousers. Using good light and a mirror, the sole of the foot, between the toes and around the heels, should be examined. A patient is looking for hard skin (early callus), cuts, corns, blisters, spots or any red or swollen areas. 

The feet should then be washed using warm water and mild soap. Do not use very hot water or soak the feet for a long period of time. Use a clean towel to dry thoroughly but gently, including between the toes. Rub some emulsifying ointment into hardened areas but not between toes. 

Never walk barefoot, even on holidays. Avoid pointed toe, high heel, plastic or slip-on shoes. Make sure shoes don’t catch or rub on one area of the foot. If there is a concern then discuss with the practice nurse or podiatrist. 

Really handy booklets are available on the HSE website and in most GP surgeries. There is also a good section on the Diabetes Ireland website about caring for your feet; www.diabetes.ie/living-with-diabetes/living-type-1/managing-diabetes/footcare/

Conclusion

Diabetes is a common disease in Ireland and foot complications are common and costly. An annual high-quality foot review is essential in general practice as well as education for patients on good foot care at home. A new model of care for the management of foot complications is available, (www.hse.ie) and there has been an uplift in podiatry posts in the community to assist with high-quality, multidisciplinary footcare.

References

1. IDF Diabetes Atlas | Tenth Edition [Internet]. [cited 2022 Nov 9]. Available from: https://diabetesatlas.org/
2. Everett E, Mathioudakis N. Update on management of diabetic foot ulcers. Ann N Y Acad Sci. 2018 Jan;1411(1):153-65 
3. Hurley L, Kelly L, Garrow AP, Glynn LG, McIntosh C, Alvarez-Iglesias A, et al. A prospective study of risk factors for foot ulceration: The West of Ireland Diabetes Foot Study. QJM Int J Med. 2013 Dec 1;106(12):1103-10 
4. Smith D, Cullen MJ, Nolan JJ. The cost of managing diabetic foot ulceration in an Irish hospital. Ir J Med Sci. 2004;173(2):89-92