OrthoNet

Diabetic Foot - Approach to Charcot Arthropathy

The classic case is the patient who arrives with swelling and discomfort in his foot after a “sprain” or minor trauma some months ago - he may or may not have been diagnosed with diabetes. This may be the presenting complaint!

History:
- pain characteristics WWF CART
- diabetic things to rule out: frequency, nocturia, thirst, weight loss
- symptoms of peripheral vascular disease
- symptoms of numbness/tingling, other wounds, fungal infections of the toes
- progressive deformity in the foot?

Physical
- motor and sensory testing is key - what is the pattern of sensory loss - pinprick, light touch, vibration/proprioception
- signs of autonomic dysfunction - skin dystrophic changes, hair loss, hyperemia, dry skin
* look for signs of pressure breakdown
- assess the deformity - ankle, hindfoot, midfoot, forefoot

Treatment
- look at the x-ray and try to make out what “Eichenholtz” stage this is
I - Dissolution (demineralization)
II - Coalescence (early healing)
III - Resolution (sclerosis and ankylosis)
- Basically, everything is NO TOUCH until the resolution stage III because of severe osteopenia and the inability to achieve good fixation and instability of the skin for healing.
- the initial treatment is therefore NON-operative.
- they are NON-WEIGHTBEARING for up to 9 months - arrange for electric wheelchair; then TEMPORIZE
- Foot up for a few days to get swelling down
- Then some form of orthosis to prevent pressure and shear: foam walker boot with soft tri-density accommodative insoles, or total contact casting, or patellar tendon clamshell brace
- They are in this for up to 9 months!

There are 3 indications to operate
1. infection - either local or spreading/systemic needs aggressive I & D or amputation
2. prophylactic pressure relief - if osseous deformity is creating a pressure ulcer that, if left untreated, will eventually break down, you might as well do the oste-ectomy to get rid of the pressure point. Good example is the LisFranc injury with prominence over the cuboid and laterally displaced 5th metatarsal - you can knock off the lateral aspect of the cuboid and metatarsal.
3. stabilization of a fracture once it is safely into the resolution stage if there is ongoing instability and pain.

Total contact casting
- pads for the pressure areas, 1 layer of soft-roll
- well moulded PLASTER cast
- cover the toes!