Published 6/1/2013
Terry Stanton

Treating Charcot Foot

The optimal treatment for Charcot foot—amputation or salvage—has been a subject of continuing debate, and not only among orthopaedic foot and ankle surgeons. The American Diabetes Association has also been working to review and summarize the evidence surrounding treatment methods for Charcot foot.

During the American Orthopaedic Foot & Ankle Society’s 2013 Specialty Day meeting, Michael S. Pinzur, MD, of Chicago’s Loyola Medical Center, examined the issue from two different perspectives. During his first presentation, Dr. Pinzur focused on the comparative cost of limb salvage versus amputation in patients with diabetes; later that day, he presented the results of a study on the use of a single stage surgery for limb salvage.

Comparing costs
Strictly on financial terms, the cost of a transtibial amputation is similar to the cost of limb salvage, at least in the first year, noted Dr. Pinzur.

His study reviewed costs over 40 months for 76 patients with diabetes-related Charcot foot deformity, including 38 patients with osteomyelitis, who underwent a single resection and correction procedure. These costs were then compared with costs for 14 patients who underwent amputation and prosthetic fitting during the same period. The average cost for patients in the limb salvage group was $57,413 versus $49,252 for those in the amputation group.

Cost of care was calculated from inpatient hospitalizations, rehabilitation or skilled nursing facilities, home health care (including parenteral antibiotic therapy and physical therapy), and prosthetic and therapeutic footwear costs.

Because this study examines the raw financial aspect of the equation and describes costs essentially for the first year following the index event, the equation might change if future procedures are needed. “Going forward, we will need more comparative data on longevity before we can make data-supported decisions,” said Dr. Pinzur.

The choice and the challenges
Dr. Pinzur noted that Charcot foot arthropathy “creates a severe negative impact on health-related quality of life for affected individuals, leading to both substantial disability and resource consumption.” He said that the trend “among experts” favors surgical correction of the deformity.

The correction has commonly been performed as a staged procedure using standard methods of internal fixation. In the first stage, resection of the infected bone is carried out, with internal fixation applied at the second operation. This protocol “is based on very limited expert opinion,” Dr. Pinzur said.

Today, however, fine-wire external fixation allows for a single-stage resection combined with correction. A multiplane fine-wire external fixator is used to maintain the correction (Fig. 1). This was the procedure used in the cost comparison with amputation.

Fig. 1
(A) A Charcot foot in a 57-year-old man with a body mass index of 36.9, and (B) circular external fixator applied after corrective surgery.
Courtesy of Michael S. Pinzur, MD

About half of patients with severe involvement have bony infection that requires either primary amputation or prolonged parenteral antibiotic therapy, Dr. Pinzur said. Amputation may be performed after attempts to resolve the infection fail. In this study, 50 percent of patients developed osteomyelitis. Once this occurs, “the decision-making algorithm becomes more complicated,” Dr. Pinzur said, and many patients eventually required amputation after attempts at limb reconstruction failed.

He noted that “comparative effectiveness financial models have recently been introduced to assist decision making on allocation of resources” and that patients with severe Charcot foot deformity may require significant resources.

In calculating costs and benefits, Dr. Pinzur said, the cost of operative correction of deformity and the long-term use of therapeutic footwear must be weighed against the encumbered activity restriction of accommodative bracing—for example, with the CROW (Charcot restraint orthotic walker) device.

“The first question that needs to be addressed is whether successful correction of the acquired deformity allows patients more independence,” he said. “If the answer is yes, will this increased independence lead to a longer survival, compared with both the impaired quality of life associated with encumbered bracing and that of a transtibial amputee?”

Many experts currently believe that successful deformity correction in patients with Charcot foot can “greatly improve quality of life, foster greater walking independence, and improve longevity,” Dr. Pinzur said. “Detractors suggest that the surgery is not justified given the cost of care and risks associated with the surgery.”

Other factors are involved in outcomes. Noting that the 1- to 2-year mortality rate following transtibial amputation in the diabetic population ranges from 25 percent to 36 percent, Dr. Pinzur said that mortality data may be skewed “with the suggestion that patients who undergo amputation for gangrene are more likely to die than those who undergo amputation for infection or a failed reconstruction attempt.”

He also noted that the average body mass index (BMI) for patients undergoing limb reconstruction is 35. “Experience would suggest that such morbidly obese patients are unlikely to achieve independent ambulation following transtibial amputation and prosthetic limb fitting,” he said.

“The next logical step would be to assess the longevity, independence, and quality of life in patients undergoing primary amputation and limb salvage,” concluded Dr. Pinzur.

Focus on the single-stage operation
When he returned to the podium later in the program, Dr. Pinzur shared results from a study on the single-stage treatment for Charcot foot that served as the index surgery for the cost study. He noted that some controversy exists over whether correction of the deformity should be accomplished at the same time as resection of chronically infected bone.

This study followed 178 patients who underwent reconstruction for Charcot foot arthropathy. The procedure included resection of infected bone, correction of deformity, parenteral antibiotic therapy, and maintenance of the correction with a static external circular fixator. At follow-up, 68 of the 71 patients with chronic osteomyelitis at the time of surgery (95.7 percent) achieved limb salvage and were able to ambulate with commercially available therapeutic footwear.

Dr. Pinzur explained that proponents of internal fixation for Charcot foot generally acknowledge that correction of deformity and placement of internal fixation should occur after bone infection is resolved and wounds are healed. However, surgical eradication of infection can be combined with correction of deformity when external fixation is used.

The antibiotic therapy used in the study was culture-specific and was administered and monitored by an infectious disease consultant, who also chose the antibiotic and duration of therapy. The fixator was maintained for 8 weeks when the deformity was confined to the foot and at least 12 weeks when the ankle was involved.

Given the multiple comorbidities commonly seen in patients with Charcot foot, Dr. Pinzur said that the multidisciplinary team approach taken in the study “has the potential to provide more efficient care for this complex patient population, while also avoiding untoward medical events and complications. The favorable results seen in this highly morbid patient population are encouraging.”

He added that, as newer methods of antibiotic delivery become available, it may become possible to administer antibiotic therapy at the time of surgery. “Until then, the best practice appears to combine aggressive surgical resection of infection with culture-specific parenteral antibiotic therapy,” he concluded.

Coauthors of the cost study were Joseph A. Gil, MD, and Adam P. Schiff, MD. Drs. Gill and Schiff were also coauthors of the surgery study, along with Jaime Belmares, MD.

Disclosure information: Dr. Pinzur—Biomimetic, SBI, Smith & Nephew, Wright Medical Technology, KCI, Foot & Ankle International, Orthopedics Today, Genij orthpadii. The other authors report no conflicts.

Terry Stanton is senior science writer for AAOS Now. He can be reached at tstanton@aaos.org

Bottom Line

  • Treating Charcot foot consumes substantial healthcare resources.
  • During the first year, the cost of surgical correction treatment was about the same as for amputation.
  • A single-stage surgical procedure with correction of deformity, resection of infection, and external fixation had largely positive outcomes.
  • A multidisciplinary team approach, including infectious disease consultation, appeared to have a positive effect.