Clinical outcome of postoperative surgical site infections in patients with posterior thoracolumbar and lumbar instrumentation

Summary

Objectives

Postoperative surgical site infection (SSI) is associated with high rates of disability, especially following instrumented spinal surgeries. The management of implant-associated SSI is challenging. This study analysed data from hospital databases to assess the incidence and characteristics related to postoperative SSI after posterior thoracolumbar and lumbar instrumentation.

Methods

Patient demographics, infection characteristics, details of treatment and perioperative factors were reviewed (January 2010–December 2020). Oswestry Disability Index (ODI), Patient Health Questionnaire-9 (PHQ-9) and Visual Analogue Scale (VAS) scores for back and leg pain were analysed preoperatively and postoperatively until final follow-up.

Results

Of the 27,881 procedures collected from the databases, 521 (1.8%) patients were diagnosed with SSI. Of these, 191 (36.7%) patients underwent at least one revision surgery for SSI. The infection rate was significantly higher in patients with lumbar spinal stenosis than in patients with scoliosis or kyphosis (P<0.01). The most commonly isolated pathogen was meticillin-susceptible Staphylococcus aureus (43.4%). The rate of complications secondary to antibiotic treatment was 7.8%, and long-term antibiotic suppression was reported in 15.2% of patients. Instrumentation was retained in 175 (91.6%) patients, and all SSIs were controlled without recurrence during follow-up.

Conclusion

Analysis of 27,881 patients showed an average SSI rate of 1.8%. Patients with deep wound SSI can be treated successfully in most cases with retention of instrumentation. Early diagnosis, positive revision surgery with strict irrigation, thorough debridement and a long-term course of antibiotics are critical to eradicate infection, retain implants, decrease morbidity and achieve wound healing.