DIABETIC FOOT ULCERS

What is a diabetic foot ulcer?

Diabetic foot ulcer is a skin sore with full thickness skin loss on the foot due to neuropathic and/or vascular complications in patients with type 1 or type 2 diabetes mellitus.

What causes diabetic foot ulcer?

Diabetic foot ulcers are caused by neuropathic and/or vascular complications of diabetes mellitus.

Neuropathic ulcer

High blood sugar levels can damage the sensory nerves resulting in a peripheral neuropathy, with altered or complete loss of sensation and an inability to feel pain. Peripheral neuropathy develops in approximately 50% of adults with diabetes, increasing the risk of injury to the feet from pressure, cuts, or bruises.

Vascular ulcer

Blood vessels can also be damaged by long-standing high blood sugar levels, decreasing blood flow to the feet (ischaemia) and/or skin (microangiopathy). This can result in poor wound healing.

What are the clinical features of diabetic foot ulcer?

A diabetic foot ulcer is a skin sore with full thickness skin loss often preceded by a haemorrhagic subepidermal blister. The ulcer typically develops within a callosity on a pressure site, with a circular punched out appearance. It is often painless, leading to a delay in presentation to a health professional. Tissue around the ulcer may become black, and gangrene may develop. Pedal pulses may be absent and reduced sensation can be demonstrated.

What are the complications of diabetic foot ulcer?

Diabetic foot ulcer is particularly prone to secondary infection resulting in:

  • Wound infection
  • Cellulitis

How is diabetic foot ulcer diagnosed?

Diabetic foot ulcer is a clinical diagnosis of a painless foot ulcer in a patient with a long history of poorly controlled diabetes mellitus.

Investigations may include:

  • Swabs for secondary infection
  • X-rays for bone involvement
  • Angiography
What is the treatment for diabetic foot ulcer?

Prevention of diabetic foot ulcer

  • Optimise diabetes control to reduce neuropathic and vascular complications
  • Smoking cessation
  • Regular examination of the at-risk foot, and careful toenail trimming
  • Prompt treatment of non-ulcerative conditions such as tinea pedis or cracked heels
  • Appropriate footwear — properly fitting soft shoes or made-to-measure insoles
  • Exercise and physiotherapy
  • Education of patient, family, and healthcare providers