Diabetic Foot For Radiologist

An elderly diabetic lady  presents with painful and swollen foot. Resident-Professor series by Dr MGK Murthy & Dr Sumer Sethi

(a)What do the X rays show ?

They show subluxations, lucencies or bones, irregularity, periosteal reaction, and Soft tissue  swelling

(b)What are the possibilities ?

 The possibilities  are Charcot’s arthropathy and osteomyelitis in diabetes

In this case  presence of ulcer, lucencies, and no fragmentation or dislocation support osteomyelitis

(c ) How do we differentiate ?

It is big clinical dilemma as both present with hot swollen foot  in diabetes. Usually infection always  reaches the bones via skin  ulcer and the presence or absence of the same is vital . Increased Blood counts and C Reactive protein positivity, absence of bilaterality help further. Presence of fragmentation and dislocations  suggest Charcots. Charcots being autonomic neuropathy presents with fragmentations, fractures, sclerosis,  and subluxations 

(d)What is the etiology of charcots?

Not known exactly . However some believe sensory neuropathy contributes by ulceration not noticed by the patient (neurotraumatic theory) and other autonomic neuropathy leading to increased blood flow and thereby the mismatch between bone synthesis and destruction