Traditional surgical techniques, in which bones are held in place by internal plates and screws, don't work with a subset of obese Charcot patients. Their bones, already weakened by complications of Charcot foot, could collapse under the patient's heavy weight.

A common treatment in such cases is to put the patient in a cast. But bones can heal in deformed positions. And, it is difficult or impossible for obese patients to walk on one leg when the other leg is in a cast. Patients typically have to use wheelchairs and are confined to the first story of the house for as long as nine months. And after the cast comes off, they must wear a cumbersome leg brace.

By contrast, patients who are treated with an external fixator often are able to walk or at least bear some weight on the treated leg. The device is attached to the leg for only two or three months.

A 2007 study by Pinzer, published in Foot & Ankle International, demonstrated the benefits of the external fixator. Pinzur followed 26 obese, diabetic Charcot foot patients who had an average body mass index of 38.3. After surgery to correct the deformity, the foot bones were held in place by the external fixator. A year or more later, 24 of the 26 patients (92 percent) had no ulcers or bone infections and were able to walk without braces, wearing commercially available shoes designed for diabetics.

Pinzur is a professor in the Department of Orthopaedic Surgery and Rehabilitation at Loyola University Chicago Stritch School of Medicine.Source : Hospital Practice