Implant Retention or Removal for Management of Surgical Site Infection After Spinal Surgery

Abstract

Study Design: A literature review.Objective: To summarize the implant removal rate, common bacterial organisms found, time of onset, ratio of superficial to deep infection, and regurgitating the prevalence among all the retrospective and prospective studies on management and characterization of surgical site infections (SSIs). Methods:PubMed was searched for articles published between 2000 and 2018 on the management or characterization of SSIs after spinal surgery. Only prospective and retrospective studies were included. Results: A total of 49 articles were found relevant to the objective. These studies highlighted the importance of implant removal to avoid recurrence of SSI. The common organisms detected were methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermis, Staphylococcus epidermis, Staphylococcus aureus, and Propionibacterium acnes, with prevalence of 1% to 15%. A major proportion of all were deep SSI, with minority reporting on late-onset SSI. Conclusion: Long-term antibiotics administration, and continuous irrigation and debridement were common suggestion among the authors; however, the key measure undertaken or implied by most authors to avoid risk of recurrence was removal or replacement of implants for late-onset SSI.

High Prevalence of Biofilms on Retrieved Implants from Aseptic Pseudarthrosis Cases

“…Recent studies have shown that repeated reprocessing and intraoperative exposure is a main source of such a biodose and other foreign bodies 12,14,15) . Literature shows that delayed-onset infection can occur from 90 days to a year from the date of surgery and constitutes between 15% to 35% of all reported infections 19) . It also shows that late-onset infection, which occurs after a period of one year from surgery, is the least studied infection type owing to the lack of long-term follow-up 19) .…”

“…Literature shows that delayed-onset infection can occur from 90 days to a year from the date of surgery and constitutes between 15% to 35% of all reported infections 19) . It also shows that late-onset infection, which occurs after a period of one year from surgery, is the least studied infection type owing to the lack of long-term follow-up 19) . The few longer-term studies (>6 years) that considered late-onset infection have shown an average time to infection detection of 56 to 80 months postsurgery with a total incidence of 9.7% 19) .…”

“…It also shows that late-onset infection, which occurs after a period of one year from surgery, is the least studied infection type owing to the lack of long-term follow-up 19) . The few longer-term studies (>6 years) that considered late-onset infection have shown an average time to infection detection of 56 to 80 months postsurgery with a total incidence of 9.7% 19) . A previous hypothesis suggests that in several susceptible patients, the 20) .…”

“…This is consistent with other studies that demonstrated a positive bacterial biodose impregnation at the screw-bone interface during spine sugery [12][13][14][15] . In addition to screw loosening, studies have shown a high rate of delayed or late-onset infection only in cases with instrumentation [16][17][18][19] . These studies support the biological pathway hypothesis, which states that many bacterial species that are known to cause infection can remain dormant in implantassociated biofilms and would later cause screw loosening or delayed/late-onset infection.…”

Progress not panacea: vancomycin powder efficacy and dose evaluated in an in vivo mouse model of spine implant infection

“…However, there are exceptions including the Martin et al retrospective comparative analyses of posterior cervical and deformity cohorts that failed to show a difference, and the sole randomized, controlled clinical trial by Tubaki et al also failed to reveal a difference in infection rates [9,18,24]. Furthermore, perioperative and late-onset infections with vancomycin susceptible organisms occur in the setting of VP use with high frequency [9,10,13,16,17,28,29]. As such, VP application should not be viewed as a panacea to bacterial inoculation of implants during surgery, and efforts to maintain sterility may necessitate vigilance well prior to surgical incision during implant processing [30].…”