TAM (Treatments and Medicines) NHS Highland- Red, oedematous, warm and possibly painful foot. Frequently crepitus can be felt
- Elevation of the Charcot foot for 1-2 hours will typically reduce inflammation whereas this will not happen with infection
- Differential Diagnosis: Infection, Gout, Soft Tissue Injury, Fracture, Arthritis, Deep Vein Thrombosis (DVT)
Charcot Neuroarthropathy in diabetes (Guidelines)
Warning
Charcot's Foot is a Medical Emergency.
- Charcot foot is an acute inflammatory condition of the neuropathic foot. There are three classical stages. The first stage leads to bone and joint destruction and fragmentation which if untreated causes foot deformity to develop. The second stage is the coalescive stage during which the destruction process slows and healing commences. A third chronic healed or ‘burnt out’ phase follows the healing process.
- Charcot foot most commonly affects people in their 40s and 50s. The cause is not known but the presentation can follow minor injury. It is commonly misdiagnosed as a sprain or as cellulitis.
- Failure to identify the condition early leads to development of foot deformity which commonly leads to foot ulceration. Typically, ulceration isn’t present in the early stages of Charcot foot although Charcot foot can develop in a previously ulcerated foot. Amputation rates are high in ulcerated Charcot feet. Differentiation from osteomyelitis is very difficult and Charcot foot and osteomyelitis can co-exist
- Charcot foot should be suspected in any patient with neuropathy who presents with a swollen, warm, erythematous foot.
Patients should be referred to the on call orthopaedic team (Page 3000).
- Undertake neurological and vascular assessment i.e. check pulses, capillary return and sensation
- Confirm or exclude infection, if possible.
- Record heat difference between limbs – affected limb usually >2oC higher than contra lateral foot.
- Blood tests –HBA1c, Erythrocyte Sedimentation Rate (ESR), C-reactive protein, Alkaline Phosphatase, Renal function, Urate, full blood count (FBC).
- X-Ray as a baseline and to exclude diabetic neuropathic fracture
- If Charcot foot is suspected but X-Ray is inconclusive, consider MRI
- Immobilisation of the foot is urgently required. Non-removable below knee total contact cast or air cast boot. Casting should continue until all signs of inflammation regress –average time in boot/cast is 9 months
- Non-weight bearing if patient is able
- There is insufficient evidence to support the routine use of bisphosphonates in the acute phase.
- Optimise glucose control.
- Regular clinical examination and imaging to monitor progress.
- Consider use of removable below knee cast.
- Allow staged return to weight bearing, in cast, when foot temperature equal and imaging indicates non-destructive phase.
- If foot remains stable, follow with staged introduction of appropriate orthotic footwear.
- Pressure relief with footwear and insoles as appropriate, via orthotics department.
- Classify patient as high risk and review regularly in podiatry for signs of long-term complications.