According to a study presented at the AAOS 2012 Annual Meeting, custom-made antibiotic-impregnated cement nails were effective in treating tibial infections that occur in patients with a tibial fracture who undergo intramedullary (IM) nailing.

Researchers conducted a retrospective study of 32 patients who underwent IM nailing of tibial fractures and in whom deep postoperative infection subsequently developed. The use of antibiotic-impregnated IM nails cleared 75 percent of the infections. In addition, persistent infections became apparent early, within the first 6 months after insertion.

Retrospective analysis
Researchers identified 32 patients who underwent IM nailing of tibial fractures between 2000 and 2010, received antibiotic nails to treat deep postoperative infection, and had at least 6 months follow-up.

Of these patients, 30 (94 percent) had initial open fractures, and compartment syndrome developed in one of the two patients with closed fractures, requiring fasciotomies. Methicillin-resistant Staphylococcus aureus (MRSA) was the most common infecting organism, found in 11 patients (34 percent), although methicillin-sensitive S aureus was the most common organism in patients with persistent infection (Table 1).

A stabilizing core, such as an Ilizarov rod or ball-tipped guide wire (based on the surgeon’s preference), was used as the core of the antibiotic nail. Vancomycin was then added to polymethylmethacrylate that already contained tobramycin. A 40 French chest tube was used as the antibiotic nail mold, and the cement was injected while still very liquid.

The surgeon’s preference, as well as each clinical scenario, also determined the number of subsequent débridement procedures and exchange antibiotic nail insertions. For a minimum of 6 weeks following insertion of the antibiotic nail, all patients received intravenous antibiotics under the direction of the infectious disease service at the institution. In addition, the treatment course for patients with recurrent infection was at the surgeon’s discretion and ranged from administration of suppressive antibiotics to revision with a Taylor spatial frame.

Analyzing the results
Of the 32 patients in the original cohort, 7 were infected with multiple organisms; 1 patient in the persistent infection group was infected with multiple organisms.

After treatment with the antibiotic-impregnated nail, 24 patients (75 percent) had no evidence of recurrent infection, while 8 patients (25 percent) had persistent or recurrent infections. In all eight patients with persistent or recurrent infection, the infection developed within the first 6 months following insertion of the antibiotic nail.

Implications and limitations
“Our study showed that antibiotic nails are effective in the treatment of infected tibial fractures,” the authors stated, while noting that more study is needed to compare the effectiveness of antibiotic nails to other treatment strategies.

The study was limited in that it was a nonrandomized, retrospective case series, which lacked standard protocols related to the numbers of débridement procedures and nail exchanges. Instead, the treating surgeon’s preference and the clinical scenario dictated these decisions.

Authors of “Do Antibiotic Nails Work for Treating Infected Tibial Fractures?” are Rachel M. Reilly, MD (no conflicts); Theodore T. Manson, MD (no conflicts); and Robert V. O’Toole, MD (Synthes and Stryker). They would like to acknowledge the assistance of Dori Kelly, MA, in preparing the manuscript.

Jennie McKee is a staff writer for AAOS Now. She can be reached at mckee@aaos.org

Bottom Line

• This retrospective case series evaluated 32 patients who underwent IM nailing of tibial fractures and in whom deep postoperative infection subsequently developed. Infections were treated with antibiotic-impregnated IM nails.
• The use of antibiotic-impregnated IM nails cleared 75 percent of infections. In addition, persistent infections became apparent early, within the first 6 months after insertion of the antibiotic nail.
• Although more study is needed, the investigators say that this study shows that antibiotic nails can be effective in treating infected tibial fractures.

Additional Resources
Do Antibiotic Nails Work for Treating Infected Tibia Fractures?