Post-sternotomy chronic osteomyelitis: is sternal resection always necessary?

The goal of this study was to investigate alternative strategies to the sternal resection in the treatment of post-sternotomy osteomyelitis. We report our experience in the treatment of chronic infection of median sternotomy following open heart surgery without sternal resection. A 4-year retrospective study was performed, consisting of 70 patients affected by post-sternotomy sternocutaneous fistulas due to chronic osteomyelitis: 45 patients underwent only medical treatment and 25 underwent steel wire removal and surgical debridement (conservative surgery). Of the 25, 7 patients underwent an additional vacuum assisted closure (VAC) therapy due to widespread infected subcutaneous tissue. The diagnosis of osteomyelitis was supported via 3D CT scan images. Complete wound healing was achieved in 67 patients including a patient who achieved healing after being affected by a fistula for over 24 years before coming under our observation, another, affected by mycobacteria other than tuberculosis osteomyelitis, who needed antimicrobial treatment for a period of 30 months and 2 who were affected by Aspergillus infection and needed radical cartilage removal. Fistula relapses were observed in 6 patients of the total 70, possibly due to the too short-term antibiotic therapy used in the presence of coagulase-negative Staphylococcus (CoNS) with multiple resistances and in the presence of Corynebacterium species. Post-sternotomy chronic osteomyelitis can be successfully treated mainly by systemic antimicrobial therapy alone, without mandatory surgical treatments, provided that accurate microbiological and radiological studies are performed. The presence of CoNS and Corynebacterium species seemed to be associated with a need for a prolonged combined antimicrobial therapy with a minimum of 6 months up to a maximum of 18 months. The CT scan and the 3D reconstruction of the sternum proved to be a good method to evaluate the status of the sternum and support the treatments. The VAC therapy was not useful in treating osteomyelitis, although, if used appropriately in the postoperative deep sternal wound infection with the sponge fitted between the sternal edges, it seems to be an effective method to eradicate the infection in the sternum and to prevent chronic osteomyelitis.