Cryopreserved bone flaps from decompressive craniectomies: a microbiological analysis.

PURPOSE: Surgical site infection (SSI) is a serious complication after cranioplasty. Due to the relatively frequent occurrence of post-cranioplasty SSI, the utility of autologous bone flap swab cultures surrounding cryopreservation as a reliable predictor has been the subject of an ongoing debate. This bicentric study aims to contribute to this topic by conducting an in-depth analysis of bone flaps obtained via decompressive craniectomies. This study had three major aims: assessments of 1) bacterial contamination of bone flaps after decompressive craniotomy, 2) impact of cryoconservation on contamination rates and 3) potential effectiveness of anti-infective treatment to reduce the germ load prior to cranioplasty. METHODS: Cryopreserved bone flaps from two centers were used. Microbiological cultivations of swabs prior to and after cryopreservation were taken and assessed for aerobic and anaerobic growth over a 14-day incubation period. Additionally, in a subset of bone flaps, swab testing was repeated after thorough rinsing with an anti-infectant (octenidine-phenoxyethanol) followed by saline. RESULTS: All 63 bone flaps (patients median age at surgery: 59 years) were obtained via decompressive craniectomies. Swabs done prior to cryopreservation revealed a 54% infection rate with Propionibacterium acnes being the most common microorganism in 65% of those cases. After thorough disinfection of the preserved bone flaps, all but one case showed no bacterial growth in swab testing. Furthermore, no relevant risk factors for bacterial contamination could be identified. CONCLUSION: This retrospective study showed the common presence of bacterial growth in cryopreserved bone flaps before and after freezing. Rinsing with octenidine-phenoxyethanol and saline effectively prevented bacterial growth in a notable percentage of cases, suggesting a potential strategy to reduce contamination. However, persistent bacterial growth in some cases underscores the need for further research to optimize antiseptic measures during autologous cranioplasty.

Wound healing after intracutaneous vs. staple-assisted skin closure in lumbar, non-instrumented spine surgery: a multicenter prospective randomized trial.

PURPOSE: Superficial surgical site infection (SSSI) is a prominent problem in spine surgery. Intracutaneous sutures and staple-assisted closure are two widely used surgical techniques for skin closure. Yet, their comparative impact on wound healing and infection rates is underexplored. Our goal was to address this gap and compare wound healing between these two techniques. METHODS: This study was a multicenter international prospective randomized trial. Patient data were prospectively collected at three large academic centers, patients who underwent non-instrumented lumbar primary spine surgery were included. Patients were intraoperatively randomized to either intracutaneous suture or staple-assisted closure cohorts. The primary endpoint was SSSI within 30 days after surgery according to the wound infection Centers for Disease Control and Prevention (CDC) classification system. RESULTS: Of 207 patients, 110 were randomized to intracutaneous sutures and 97 to staple-assisted closure. Both groups were homogenous with respect to epidemiological as well as surgical parameters. Two patients (one of each group) suffered from an A1 wound infection at the 30-day follow up. Median skin closure time was faster in the staple-assisted closure group (198 s vs. 13 s, p < 0,001). CONCLUSION: This study showed an overall low superficial surgical site infection rate in both patient cohorts in primary non instrumented spine surgery.