Charcot foot (diabetic Charcot arthropathy)
What it is
Charcot arthropathy is a progressive, destructive neuropathic arthropathy that occurs almost exclusively in patients with diabetic peripheral neuropathy.
Loss of protective sensation and altered biomechanics permit repetitive, often unperceived trauma with a local inflammatory response that promotes bone resorption, fragmentation and joint instability.
Left untreated the process commonly produces mid‑foot collapse - the classic “rocker‑bottom” deformity - with high risk of recurrent ulceration and limb‑threatening infection (NICE NG19).
Key clinical features
- Typical presentation: a patient with long‑standing diabetes and peripheral neuropathy who develops an acute, usually unilateral, warm, red and swollen foot or ankle. Pain may be absent or only mild because of neuropathy.
- Hallmark deformity: progressive collapse of the longitudinal arch producing a convex (“rocker‑bottom”) plantar surface.
- Helpful clinical clues: absent protective sensation on 10 g monofilament testing, impaired vibration/reflexes, a warm foot several degrees hotter than the contralateral side (a temperature difference ≥2°C supports active disease), and a recent history of minor trauma or increased footwear pressure.
Why early recognition matters
Active Charcot is best treated by immediate off‑loading and immobilisation to prevent further bone damage and deformity. Prompt multidisciplinary specialist involvement markedly reduces the need for surgical reconstruction and the risk of complications (NICE NG19).