Annual review of the diabetic patient is important to include, or even focus to, the diabetic foot evaluation. Early recognition of the foot at risk is crucial to prevent further damage and begin treatment at a reversible stage. Skin and nails should be inspected (dry skin, cracks, calluses, fungal infections, onychomycosis etc) in order to ensure proper advice/treatment. Footwear and corresponding advice about proper fit, how to choose new shoes, how to inspect etc are important too. Review should include assessment of risk factors for ulceration: previous ulcers, previous lower extremity amputation, duration of diabetes, glycaemic control, impaired vision and nephropathy. Furthermore, the following should be documented, at least on an annual basis.

1. Neuropathic Assessment

Detailed history for symptoms such as burning, numbness, pain and tingling. Examination for muscle atrophy, foot deformities, loss of hair, discoloration of the skin, nail changes. Sensory assessment should include pressure, vibration, pain or temperature, and joint position sensation. Inability to perceive pressure (specified manoeuvres) on the plantar surface indicates large-fibre neuropathy and studies have shown to predict appearance of ulcers with 66-91% sensitivity. Testing 4 plantar sites on the forefoot identifies 90% of cases with insensate foot.

2. Structural Assessment

Foot examination for deformities is crucial (calluses, hammer toes, claw toes, flat foot etc). Load distribution to the plantar surface when standing and walking is measured and gives very useful information for ulcer prevention. Presence of Charcot neuroarthropathy may go unnoticed by the patient and is important to identify it. 16% of all diabetics with an ulcer have Charcot arthropathy, and 30% of these have both their feet suffering from Charcot arthropathy.

3. Vascular Assessment

Peripheral Vascular Disease is more frequently diagnosed in diabetics. Pulse palpation can be used initially, and Ankle Brachial Pressure Index is more accurate in assessing established peripheral vascular disease. Doppler arterial waveform is most often used as a tool for assessing vascular status, regardless of the presence of neuropathy.

4. Ulcer assessment (when it appears)

Ulcer development requires close monitoring of its progress. Identifying infection is essential for management of an ulcer in the diabetic foot. Cultures should be taken, preferably using tissue specimens rather than wound swabs. Investigation should include full blood count, markers of inflammation and an x-ray. Under certain circumstances, MRI, CT scan, bone scan and leuco-scan may aid management. Usual pathogens in diabetic foot infected ulcers are gram (+) cocci (eg Staph aureus, β haemolytic Strept). Chronic ulcers tend to have mixed-bacteria infections, and some bacteria (pseudomonas aeroginosa, enterococci) are often colonizers in this setting and not the single cause of an infection.

Identification of underlying osteomyelitis, when present, is vital and often challenging. It can be expected when bone is exposed or palpable from the examiner. It may also need detailed investigation to assess possible extent and optimal management, which may need surgical treatment. Caution should be taken though, as bone deformity may not represent osteomyelitis in the diabetic foot. Neuropathy and Charcot foot may appear as non-infectious bone lesions!