Cath Lab Digest

Study Suggests Benefit Of Conservative Surgery For Diabetic Foot Osteomyelitis

Could conservative surgery have an impact in treating osteomyelitis in the diabetic foot? A recent study published in Diabetologia found that surgery without amputation was successful in nearly half of the patients with diabetic foot osteomyelitis.

   In the study, researchers assessed 185 consecutive patients with diabetic foot osteomyelitis and histopathological confirmation of bone involvement. Histopathological analysis revealed that 50.8 percent of patients had acute osteomyelitis, 23.2 percent had chronic osteomyelitis and 24.3 percent had acute exacerbation of chronic osteomyelitis. Furthermore, researchers isolated Staphylococcus aureus in the cultures of 51.3 percent of the patients and 35 of these patients had methicillin-resistant Staph aureus (MRSA).

   As the study notes, over 49 percent of patients received conservative surgery, which did not consist of amputation, over 42 percent of patients underwent minor foot amputations and 8 percent had major amputations. Five patients died in the perioperative period, according to the study.

   For the 91 patients who underwent conservative surgical procedures (without local or high-level amputation), researchers found that nearly half of these patients had a successful result. The study authors did note that the risks of conservative surgery for diabetic foot osteomyelitis include exposed bone, ischemia and necrotizing soft tissue infection.

Weighing The Pros And Cons Of Different Treatment Options

William Jeffcoate, MD, believes the opinion of osteomyelitis is “changing quite fast” in the United States. He says the traditional advice was to remove all infected and necrotic bone. However, Dr. Jeffcoate says this changed 20 years ago when it became apparent that beta lactams/lactamase combinations and quinolones might be effective. Several studies have shown that non-surgical management of osteomyelitis may arrest infection in about 70 percent of patients, according to Dr. Jeffcoate, who practices in the Foot Ulcer Trials Unit in the Department of Diabetes and Endocrinology at City Hospital in Nottingham, U.K.

   Nicholas Bevilacqua, DPM, says it is difficult to eradicate infection in bone solely with antibiotics as devitalized bone and soft tissue impede healing and provide an ongoing nidus for infection. He says the combination of conservative surgery with antibiotics has the advantage of ensuring that all the infection has been eliminated.

   A potential disadvantage is that conservative surgery carries increased risk and at times may result in amputation, according to Dr. Bevilacqua, an attending surgeon at the Foot and Ankle Clinics and Amputation Prevention Center at Broadlawns Medical Center in Des Moines, Iowa.

   The Infectious Diseases Society of America (IDSA) guidelines list four scenarios in which Dr. Bevilacqua says one might consider non-surgical management of osteomyelitis in the diabetic foot. These scenarios include:

• when there is no acceptable surgical target;

• when the patient has ischemia caused by non-bypassable vascular disease but seeks to avoid amputation;

• when infection is confined to the forefoot and there is minimal soft-tissue loss; and

• when surgical management has excessive risk or is otherwise not appropriate or desirable.

   As far as surgical intervention goes, Dr. Jeffcoate notes there is little data although two recent studies note a high rate of recurrence and the need for more surgery. He cites one surgical series by Henke that noted a 23 percent rate of major amputation in patients who were hospitalized with osteomyelitis.

   “People are beginning to accept that perhaps we do not yet know the best way to manage pedal osteomyelitis. The adverse effects of the treatment need to be taken into account as well as the effectiveness,” emphasizes Dr. Jeffcoate.