Efficacy of Intraoperative Implant Prophylaxis in Reducing Intraoperative Microbial Contamination.

STUDY DESIGN

A prospective single-center study.

OBJECTIVES

Assess to what degree contamination of pedicle screws occur in standard intraoperative practice and if use of an impermeable guard could mitigate or reduce such an occurrence.

METHODS

Two groups of sterile prepackaged pedicle screws, one with an intraoperative guard (group 1) and the other without such a guard (group 2), each consisting of 5 samples distributed over 3 time points, were loaded onto the insertion device by the scrub tech and left on the sterile table. Approximately 20 minutes later, the lead surgeon who had just finished preparing the surgical site touches the pedicle screw. Then instead of implantation it was transferred to a sterile container using fresh clean gloves for bacterial and gene analysis. Guarded screw implies that even after unwrapping from the package, the screw carries an impermeable barrier along its entire length, which is only removed seconds prior to implantation.

RESULTS

The standard unguarded pedicle screws presented bioburden in the range of 10 to 10 (colony forming units/implant) with bacterial genus mostly consisting of and , the 2 most common genera found in surgical site infection reports. The common species among them were , , , and , whereas the guarded pedicle screws showed no bioburden.

CONCLUSIONS

Shielding the pedicle screws intraoperatively using a guard provides a superior level of asepsis than currently practiced. All unshielded pedicles screws were carrying bioburden of virulent bacterial species, which provides an opportunity for the development of postoperative infections.