Spinal Implant Failure Caused By Microbes On Explanted Pedicle Screws

Pedicular screws are often used to protect equipment implanted surgically in the spine in patients with paraplegia. In some cases, these screws release over time, leading to spinal instability and the resulting pain. This is a common complication of spinal surgery. One of the reasons proposed to loosen the pedicle screw is implant infection, but so far little clinical evidence has been provided to support this theory.

The study included 82 patients who underwent surgery in which a material implant had to be removed from the spine. None of these patients had clinical signs or laboratories of active infection and there was no evidence of obvious infection during surgery. After the operation, the sonication was used to detect the presence of microbial biofilms in the extracted material. This application of sound energy breaks down any sticky biofilm that covers the surgical implants and separates the microorganisms that inhabit them. The microorganisms that colonized the implants were then inspecting to detail the types present.

The authors found signs of pedicle screw release in 54 of 82 patients; the other 28 patients formed a control group. The sonication verified the microbial colonization of the material extracted with one or more bacteria in 22 (40.7%) of the 54 patients with pedicle screw release. The sonication showed that no microbial colonization in the material was removed from the 28 patients in whom there was no detachment of the pedicle.

Based on the relationship between pedicle screw release and microbial colonization, the authors recommend that patients whose infected material was replaced would benefit from a systemic antibiotic-active-biofilm treatment to avoid additional bolus release the perioperative colonization of implants to disrupt biofilms and actively seek implant infections using advanced sonication and microbiological scrutiny at the time of reoperation.