Write a short note on Diabetic Foot.

The Concept — a Triad of Problems

The diabetic foot is a major cause of morbidity, and its complications arise from the combination of three factors produced by diabetes: neuropathy, ischaemia and impaired resistance to infection. Understanding this triad explains why a trivial injury can progress rapidly to ulceration, gangrene and amputation.

The Three Factors

• Neuropathy — sensory loss removes the protective pain that would normally warn of injury (so trauma goes unnoticed); motor neuropathy causes deformity and abnormal pressure points; autonomic neuropathy dries the skin (fissures) and alters blood flow.
• Ischaemia — accelerated peripheral arterial disease reduces the blood supply needed for healing.
• Infection — impaired immunity and hyperglycaemia allow infection to establish and spread rapidly.

Clinical Features & Management

These produce ulcers (a neuropathic ulcer is painless and over a pressure point/sole; an ischaemic ulcer is painful and at the margins/toes), the Charcot foot (progressive bony destruction of an insensate foot), cellulitis, osteomyelitis and gangrene. Management is multidisciplinary: strict glycaemic control, meticulous foot care and patient education, pressure offloading, wound debridement, antibiotics for infection, and revascularisation for ischaemia, with amputation reserved for severe or unsalvageable disease. Prevention through regular foot screening in a diabetic foot clinic is central.

Neuropathic VS Ischaemic Foot

Distinguishing the predominantly neuropathic from the predominantly ischaemic foot guides treatment. The neuropathic foot is warm and well-perfused with bounding pulses but insensate, developing painless ulcers over pressure areas and Charcot deformity — managed by offloading and foot care. The ischaemic (neuro-ischaemic) foot is cold with absent pulses and painful marginal ulcers — needing revascularisation. Many diabetic feet are 'neuro-ischaemic', combining both, which is why ABPI/Doppler assessment of the circulation is part of every diabetic foot review.

The Bottom Line

The diabetic foot results from neuropathy + ischaemia + infection, producing neuropathic (painless, pressure-point) or ischaemic (painful, marginal) ulcers and Charcot foot, managed by an MDT with glycaemic control, offloading, debridement, antibiotics and revascularisation.

A Note on Osteomyelitis & Probing to Bone

A crucial complication is osteomyelitis underlying a diabetic foot ulcer, which greatly complicates healing. A useful bedside sign is the 'probe-to-bone' test — if a sterile probe passed into the ulcer reaches bone, osteomyelitis is likely — supported by X-ray, MRI and inflammatory markers. Recognising bone infection matters because it usually requires prolonged antibiotics and often surgical debridement or partial amputation, and its presence changes the whole management plan.

Loss of protective sensation is the root cause — hence foot care education.

• Diabetic foot complications arise from a triad: neuropathy (sensory loss, deformity, dry skin) + ischaemia (pad) + impaired resistance to infection.
• Neuropathic ulcer: painless, over pressure points/sole; ischaemic ulcer: painful, at margins/toes; also Charcot foot, cellulitis, osteomyelitis, gangrene.
• Manage with a multidisciplinary team: glycaemic control, foot care/education, offloading, debridement, antibiotics, revascularisation.
• Amputation for severe disease; prevention by regular foot screening is central.