Due to advanced peripheral nerve dysfunction associated with diabetes (diabetic neuropathy), patients' feet have a dryness of the skin and a reduced ability to feel pain (nociception). Hence, minor injuries may remain undiscovered and subsequently progress to a full-thickness diabetic foot ulcer. Moreover, foot surgery is well tolerated without anaesthesia.[2] The feet's insensivity to pain can easily be established by 512 mN quantitative pinprick stimulation.[3]
In diabetes, peripheral nerve dysfunction can be combined with peripheral artery disease (PAD) causing poor blood circulation to the extremities (diabetic angiopathy).[4] Around half of the patients with a diabetic foot ulcer have co-existing PAD.[5][6] Vitamin D deficiency has been recently found to be associated with diabetic foot infections and increased risk of amputations and deaths.[7]
Research estimates that the lifetime incidence of foot ulcers within the diabetic community is around 15% and may become as high as 25%.[8]
Where wounds take a long time to heal, infection may set in, spreading to bones and joints, and lower limb amputation may be necessary. Foot infection is the most common cause of non-traumatic amputation in people with diabetes.[9]
^Formosa C, Cassar K, Gatt A, Mizzi A, Mizzi S, Camileri KP, Azzopardi C, DeRaffaele C, Falzon O, Cristina S, Chockalingam N (November 2013). "Hidden dangers revealed by misdiagnosed peripheral arterial disease using ABPI measurement". Diabetes Res Clin Pract. 102 (2): 112–6. doi:10.1016/j.diabres.2013.10.006. PMID24209599.