Diabetic Foot OSCE Examination

1. Introduction
2. General Inspection
3. Closer Inspection of the Feet
4. Palpation and Temperature
5. Vascular Assessment
6. Neurological Assessment
7. Footwear and Gait
8. Completing the Examination
9. Quiz

Wash your hands thoroughly and don personal protective equipment if appropriate.

Introduce yourself to the patient and ensure to mention your grade e.g. 3rd year medical student/junior doctor/consultant.

Confirm the patient’s details taking 3 points of identification usually; full name, date of birth and NHS/hospital number.

Obtain consent for the examination, ensuring to explain what the examination will entail. A useful explanation is that you would like to look at their feet, feel the pulses, and test the feeling in their feet to make sure their diabetes is not affecting them.

Ensure the patient is positioned comfortably on the bed or couch, and adequately expose both lower limbs to the knee, removing both shoes and socks. It is important to examine both feet so the two sides can be compared.

Ask the patient if they have any pain anywhere before you begin, and watch their face for signs of discomfort throughout. Remember that in advanced neuropathy the foot may be painless even in the presence of significant pathology, so the absence of pain is itself a relevant finding.

Begin with a general inspection of the patient from the end of the bed. Look for clues that the patient has diabetes and that it may be poorly controlled, such as the patient appearing unwell, signs of weight loss, or evidence of complications elsewhere. Note any obvious limb amputations on the contralateral side, as a previous amputation is one of the strongest risk factors for further ulceration and amputation.

Inspect the area around the bedside for objects and equipment that give clues about the patient’s condition and management. Useful findings include blood glucose monitoring equipment, an insulin pen or pump, mobility aids such as a walking frame or wheelchair, specialist footwear or orthotics, and dressings or wound care supplies which suggest existing ulceration.

Be alert to signs of sepsis in a patient with an infected diabetic foot, as this should prompt urgent escalation.

Inspect both feet carefully and systematically, comparing one side with the other. Make sure to examine the dorsum, the sole, the heel, the sides of the feet, and crucially the skin between every toe, as ulcers and fungal infection are easily missed in these hidden areas.

Look at the skin for the following:

• Ulcers – the most important finding. Note the site, size and appearance. Neuropathic ulcers are typically painless, have punched-out edges with surrounding callus, and occur over pressure points such as the metatarsal heads and heel. This is because loss of protective sensation allows repetitive trauma to go unnoticed. Ischaemic ulcers tend to be painful and occur at the tips of the toes or other peripheral ‘watershed’ areas where perfusion is poorest.
• Callus formation – thickened skin over pressure areas indicates abnormal load distribution, often as a consequence of neuropathy and deformity. Callus can act as a foreign body, raising the pressure on underlying tissue and predisposing to ulceration.
• Colour changes – a pale or white foot suggests poor arterial supply, whilst a dusky, red or black area may indicate critical ischaemia, infection or gangrene. Redness that does not blanch may represent cellulitis.
• Signs of infection – erythema, swelling, discharge or an offensive smell. Spreading erythema suggests cellulitis, and a deep, malodorous ulcer raises concern for underlying osteomyelitis.
• Dry, cracked skin and loss of hair – autonomic neuropathy reduces sweating, leaving the skin dry and prone to fissuring, which provides a portal of entry for bacteria. Hair loss over the toes and dorsum of the foot is a sign of chronic arterial insufficiency.
• Nail changes – thickened, discoloured nails may indicate fungal infection (onychomycosis), and poorly trimmed or ingrowing nails can be a source of trauma and infection.

Image - A neuropathic ulcer on the heel of a diabetic foot. Note the punched-out appearance over a pressure point, which develops because loss of protective sensation allows repetitive trauma to go unnoticed

Creative commons source by Jonathan Moore [CC BY 3.0 (https://creativecommons.org/licenses/by/3.0)]

Next, look at the overall shape and structure of the foot for deformity, which alters the way pressure is distributed across the sole and creates new high-pressure points at risk of ulceration:

• Clawing or hammer toes – motor neuropathy weakens the small intrinsic muscles of the foot, leaving the long flexors and extensors unopposed. This pulls the toes into a clawed position and pushes the metatarsal heads downwards, exposing them to high pressure.
• Loss of the foot arches and abnormal pressure loading.
• Charcot foot (Charcot neuroarthropathy) – in a patient with dense neuropathy, repeated unperceived microtrauma and an exaggerated inflammatory response cause progressive destruction of the bones and joints of the midfoot. The arch collapses, producing the characteristic ‘rocker-bottom’ deformity. In its acute phase the foot is typically warm, red and swollen, and is frequently mistaken for infection or gout – recognising it is important because the foot must be offloaded urgently to prevent permanent deformity.

Image - A Charcot foot with collapse of the midfoot producing the characteristic rocker-bottom deformity, with overlying skin changes at the new pressure point

Creative commons source by Medicalpal [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)]

Finally, look for any scars from previous surgery or amputations (including amputation of individual toes), as these confirm previous foot disease and place the patient in a high-risk category.

Before palpating, check again that the patient is not in any pain. Using the dorsal (back) surface of your hand, assess and compare the temperature of both feet, working from the toes upwards. The back of the hand is used because the skin here is thin and more sensitive to temperature differences.

A cold foot suggests poor arterial supply and peripheral arterial disease. A generally warm foot is reassuring for perfusion, but a localised area of warmth is significant: it may indicate infection or an acute Charcot foot. Comparing the two feet is essential, as a unilateral difference is far more informative than absolute temperature.

Gently palpate any areas of callus or suspected ulceration. A useful clinical sign is to feel for fluctuance or crepitus, which may suggest a deep abscess or gas-forming infection respectively. Be gentle and stop if the patient is uncomfortable.

Preview the Diabetic Foot OSCE Examination quiz