2020 Volume 11 Issue 10 Pages 1234-1240
Introduction: Surgical site infection (SSI) is still an important complication after spinal instrumentation surgery. The decision whether to removal of implant, especially management of cage, after transforaminal lumber interbody fusion (TLIF) is difficult to make. The purpose of this study was to investigate the treatment strategy for deep SSI after posterior lumber interbody fusion.
Method: We performed mini-open TLIF on 504 patients between January 2014 and February 2018, of which 14 patients (2.8%) developed SSI. The retrospective study cohort consisted of the 14 patients (mean age, 71.3 years) who had required surgical intervention for SSI. Patients were treated with aggressive surgical irrigation and debridement (I and D) with retention of implants in cases of early infection. Implant removal, extension of fusion, and re-implantation were considered in cases of screw or cages loosening or persistent infection. Each treatment course was reviewed for the type of surgery, management of implants, additional procedures. Outcomes were categorized into two groups: 1) Treatment success, which was defined as eradication of infection after I and D, 2) treatment failure, which was defined as a recurrent infection, removal of implants to eradicate the infection, or re-implantation due to loosening of screw or cages.
Result: The median time from index surgery to initial treatment was 18.5 days (range 5-320). SSI occurred within 30 days in 8 cases (57%), within 30-90 days in 5 cases (36%), 1 case (7%) after the index surgery. Treatment success was achieved in 5 (36%) cases. Of the remaining 9 cases (64%) from the treatment failure group, 5 cases were treated with removal of cages and replacement with iliac bone graft, 3 cases were treated with re-implantation without removal of the cage, and only one case required removal of screws and cages. The average degree of correction loss was 5.7±5.1°, and the fusion rate was 71% at final follow-up. Higher rate of treatment success was observed in cases with presence of osteomyelitis (20% vs. 78%, P=0.091). There were no significant differences in terms of duration of diagnosis for SSI, operation time, and estimated blood loss between the two groups. 57% (8/14) out of all cases were treated with successfully without the removal of cages and screws.
Conclusions: Postoperative spine infections were treated with aggressive surgical irrigation and debridement in cases that showed early infection. Evaluations using CT and MRI are helpful to decide the treatment strategies. Removal of the cage and extension of the fixation or re-implantation may be useful strategies in cases of osteomyelitis.