Key Considerations In Managing The Charcot Foot
Despite surgical timing in regards to the stage of Charcot, internal fixation facilitates the realignment and establishment of a plantigrade foot at the level of the fracture dislocation, particularly at the tarsometatarsal level. Large-frame external fixators have been credited for affording a more comprehensive reconstruction of the Charcot joint by ultimately allowing one to re-establish the rearfoot-to-leg and forefoot-to-rearfoot relationships. Such frames have also allowed for postoperative weightbearing in patients as early as one week. Pin tract infection rates vary widely in the literature and the fixation device does need to remain intact for an average of three months.
Using mini external fixation devices has been briefly discussed in the correction of Charcot joints.11 These devices, in conjunction with pinning or internal fixation, allow for an external structural frame to support the established arthrodesis and maintain stability. Although they do not facilitate early weightbearing, the mini external fixation devices are an excellent addition to internal screw fixation or percutaneous pinning with Steinmann pins.
Case Study: Treating A Patient With Increased Redness And Swelling In The Right Foot
A 58-year-old patient with longstanding diabetes and a previous history of ulceration and neuropathy presented to the outpatient clinic with complaints of increasing redness and swelling to his right foot.
He related that his primary care physician had seen him due to concern for a foot infection. However, the physician ordered X-rays and subsequently told the patient he had a fracture. The physician placed him on oral antibiotic therapy and sent him to the podiatry clinic for further workup.
The patient denied any direct trauma to the foot or excessive changes in activity level. He complained of mild pain and admitted to fluctuating blood glucose levels. His past medical history was significant for diabetes, neuropathy and hypertension and no tobacco history.
Physical examination revealed an obese male with palpable pedal pulses to the left foot and non-palpable dorsalis pedis on the right foot with a bounding posterior tibial pulse. He had absent protective and vibratory sensation bilaterally with increased skin temperatures to the right foot. The right foot was erythematous dorsal to the second through fifth metatarsals and edematous. We noted no ulcerations, macerations or fissures. Radiographs revealed dorsal dislocation at the tarsometatarsal joint, resulting in a divergence of the joint complex.
We proceeded to emphasize cast immobilization until we achieved a reduction of edema and an equilibrium with the skin temperatures of the lower extremities. We continued the oral antibiotic therapy with Keflex in order to prevent infection due to deep bleeding from the fracturing or skin irritation from the edema.
However, the tarsometatarsal was freely mobile and remained unstable during the four-week immobilization period. Due to the instability, we discussed surgical arthrodesis. We pursued this by using percutaneous Steinman pinning and a Synthes mini external fixator to add a structural framework around the fusion site. We added bone morphogenic protein at the arthrodesis sites to promote fusion.
We subsequently emphasized non-weightbearing in a posterior splint and weekly clinic visits for pin care until the patient achieved radiographic union. At that time, we removed the fixation and initiated progressive weightbearing in a removable cast boot (i.e. CAM walker) for three to four weeks.
We repeated radiographs and once we determined that the patient had maintained osseous integrity, we placed the patient in extra-depth shoes with custom-molded insoles for long-term maintenance.
Dr. Steinberg (pictured) is an Assistant Professor in the Department of Surgery at the Georgetown University School of Medicine in Washington, D.C.