Charcot neuroarthropathic (CN) foot and Diabetic foot Osteomyelitis (DFO) are two differential complications that occur due to diabetes. CN and DFO are notoriously troublesome to differentiate at initial presentation. Therefore, podiatrists that are presented with a diabetic foot patient suspected of OM or CN, must be extremely vigilant in diagnosing these entities as treatment vastly differs– a wrong treatment can cost someone their limb, and their lives.
Submitted: March 2016
Authors: Rossi Bad
Title: A summary of the differences between Charcot Foot and Osteomyelitis.
Charcot Neuroarthropathic Foot
Elevated leg may reduce erythema
Will not affect the localized erythema
Associated with long standing diabetic, and Leprosy
History of diabetic foot ulcers, open fracture, and deep wounds (probe to bone)
MRI shows diffused bone edema particularly in multiple joints, and articular surfaces i.e. peri-articular and subchondral edema
MRI would show localized bone edema
FDG PET is diffused and <2 i.e. lesser glucose uptake
FDG is localized and >3 i.e greater glucose uptake
Affects toes and forefoot
May appear grossly as a “deformed” foot. i.e. rockerbottom foot
Foot shape may be normal
Pulses may be bounding
Pulses may be normal to non-existent
ESR non-elevated ( in NON-ACUTE stage)
ESR elevated ( 70 mm/hr)
Radiograph will show non-specific changes: periosteal reaction, joint dislocation, fractures
Radiograph will show focalized cortical destruction with involucrum, sequestrum, clocoae,
Bone biopsy to rule out osteomyelitis
Bone biopsy is the gold standard, and can guide treatment plan
The following is a table of common podiatry classifications. They do not describe the classification in detail, but serves …..as a stepping stone. It is paramount that you first know what the system describes.
How to remember
Jahss (1st MPJ dislocation)
“Wat–saw [the] navicular”
Rowe (calcaneus – extraarticular)
“go out and Rowe [your boat] in the Essex river”
the calcaneus looks like a boat too! out = extraarticular, in = intraarticular.
Essex-Lopresti (calcaneus – intraarticular)
Out of the types of calcaneal classifications (Rowe, Sanders, Essex-lopreseti) it has TWO words=> 2 types of essex-lopresti
Bernt-Hardy (talar dome lesions)
“talar dome lesions are hard to see”
talar dome lesions are commonly missed on normal radiographs (50%)
Lauge-Hansen (ankle fx)
refers to ankle fractures! the ankle is large compared other classifications. you prob. should know this classification anyways.
“queen lis-abeth [and king frank] lives in a castle. ”
if you remember the above, then you can associate QUENU (sounds like queen with this classification. recall that hardcastle elaborated on quenu)
Sanders (CT calcaneus)
“FEEL THE BERN…from the CT machine”
CT would most likely be used for intra-articular fractures, so this is an intra-articular classification, for the calcaneus. Say it with me: Feel the bern of the coronal CT of the calcaneus –lol?
Danis-Weber (fibula fx)
Danis-Weber goes with Salter-Harris. Remember the ABCDanis -Weber. Visualize three locations (A,B,C) with respect to the ankle mortise. Since the mortise involves the tibia, these fractures have to be wrt the FIBULA.
Salter-Harris (tibia fx)
See above. S-same SalTEr- TIBIAL EPIPHYSEALradiopaedia.