Takahashi H, Okuyama K, Toki Y, Funayama T, Noguchi H, Miura K, Gamada H, Okuwaki S, Ogata Y, Sakashita K, Sunami T, Nakagawa T, Fujii K, Ishikawa T, Kim G, Ota M, Inada T, Himeno D, Takaoka H, Suzuki M, Maki S, Inoue M, Inage K, Shiga Y, Furuya T, Eguchi Y, Orita S, Ohtori S, Yamazaki M, and Koda M
Introduction: Surgical site infection (SSI) is one of the most serious postoperative complications following instrumented spinal surgery. We previously reported the potential of continuous local antibiotic perfusion (CLAP) to retain implants for patients with SSI following instrumented spinal surgery. We conducted a retrospective multicenter study to elucidate the efficacy and limitations of CLAP for patients with SSI following instrumented spinal surgery., Methods: A total of 40 patients treated with CLAP for SSI after instrumented spinal surgery were included in this study. The implant retention rate was calculated. We investigated the influence of age, presence of diabetes, number of fused vertebrae, causative pathogens, duration from diagnosis to CLAP initiation, white blood cell (WBC) count (× 10 3 /μL), and C-reactive protein (CRP) level on the development of SSI after CLAP. Patients were divided into two groups: a favorable outcome group (n = 28), in which SSI was promptly controlled after CLAP, and a poor outcome group (n = 12), in which additional surgery was required or fatal outcomes occurred after CLAP. The relationship between these two groups was evaluated., Results: In 13 of 40 patients, implants had already been removed before CLAP initiation. Excluding these cases, control of SSI with implant retention was achieved by CLAP in 22 of 27 patients (81%). In the poor outcome group, antibiotic-resistant pathogens were detected at a higher rate than in the favorable outcome group (p = 0.022), and the WBC counts at 1 week after CLAP were significantly increased compared with the favorable outcome group (poor outcome group 7.7 ± 2.4, favorable outcome group 5.8 ± 1.6; p = 0.013)., Conclusions: Application of CLAP enabled SSI control with a high rate of implant retention. However, detection of antibiotic-resistant pathogens and increased WBC count 1 week after initiating CLAP may predict poor control of SSI, even after CLAP., Competing Interests: Declarations. Conflict of Interests: All the authors, including Hiroshi Takahashi, Kohei Okuyama, Yasunori Toki, Toru Funayama, Hiroshi Noguchi, Kousei Miura, Hisanori Gamada, Shun Okuwaki, Yosuke Ogata, Kotaro Sakashita, Takahiro Sunami, Takane Nakagawa, Kengo Fujii, Tetsuhiro Ishikawa, Geundong Kim, Mitsutoshi Ota, Taigo Inada, Daisuke Himeno, Hiromitsu Takaoka, Masahiro Suzuki, Satoshi Maki, Masahiro Inoue, Kazuhide Inage, Yasuhiro Shiga, Takeo Furuya, Yawara Eguchi, Sumihisa Orita, Seiji Ohtori, Masashi Yamazaki, and Masao Koda, declare that there is no conflict of interest. Ethical Approval: The present study was approved by the ethics committees of the University of Tsukuba (Tsukuba Clinical Research & Development Organization, approval No. H30-087) and Ethics Committee of Chiba University School of Medicine (approval No. 2030). The study was conducted in accordance with the Helsinki Declaration of 1964 and its later amendments. Informed consent was obtained from all patients for the off-label use of gentamicin, participation in the study, publication of the study, and use of their data., (© 2025. The Author(s).)