Acute versus chronic charcot.

A hot red foot in acute Charcot neuro-osteoarthropathyThe differential diagnosis is infection (osteomyelitis, cellulitis, septic arthritis), inflammation (gout, rheumatoid arthritis) and deep vein thrombosis.

Here a radiograph of a patient with diabetic neuropathy and a red hot foot.
In the acute stage, the radiographs are normal and may not exclude the diagnosis of acute Charcot neuro-osteoarthropathy.

Within 4 months there is progressive decrease of calcaneal inclination with equinus deformity at the ankle.
There is destruction of the tarsometatarsal joint with the typical rocker-bottom deformity.

Bony debris is seen on the dorsal aspect of the foot.

Here MRI images of a patient with acute Charcot neuro-osteoarthropathy.
The bone marrow edema typically is not restricted to one or two bones, but is seen in the entire midfoot.
Bone marrow edema and its enhancement are typically centered in the subchondral bone, suggesting articular disease.
The subcutaneous tissues are relatively normal and there is no ulcer or other signs of infection.

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