Treatment of deep surgical site infection after posterior spinal fusion and instrumentation in spinal deformity

English Keywords:Spinal deformity  Surgical site infection  Implants  Irrigation and drainage

English Abstract:

  【Abstract】 Objectives: To evaluate the efficacy of management for deep surgical site infection after posterior spinal fusion and instrumentation in spinal deformity. Methods: A total of 167 patients underwent posterior spinal fusion and instrumentation due to spinal deformity from June 2012 to December 2014. Eleven patients(8 females and 3 males) were diagnosed with deep surgical site infections with an average age at admission of 14.6±4.7 years(range, 11-27 years). Among the 11 cases, 9 cases had early postoperative infections(within 90 days after surgery), the other 2 cases had late infections(more than 90 days after surgery). Among the 9 early infections, 6 patients were culture positive, including 2 cases for resistant methicillin-resistant Staphylococcus aureus (MRSA), 3 cases for methicillin sensitive Staphylococcus aureus(MSSA), and 1 case for Escherichia coli. The other 3 cases were culture negative and were diagnosed based on wound purulent exudation, continuous pain and a large amount of purulent fluid in the wound during debridement. The 2 cases with late infections presented with low back pain at 7 months and 10 months after the index surgery, the MRI examination showed that the formation of deep effusion, and the inflammatory indexes(ESR, CRP) were significantly higher than the baseline values, and the culturing of tissue was Staphylococcus epidermis. All the 11 cases were surgically treated with thorough debridement, continuous irrigation and drainage, and adjutant antibiotics therapy. Results: All the 9 early infections had wound healed after continuous irrigation. The removal of instrumentation was not necessary in any patient, and there were no signs of infection and implant loosening at follow-up for a duration of 13.5±5.8 months(range, 6-36 months). While the 2 late infections required multiple debridement, and required implant removal eventually at 12 months after index surgery. At 6 months and 14 months follow-up respectively, there was no recurrence of infection, but 25° and 17° loss of correction was noted respectively. Conclusions: Along with sensitive antibiotic treatment, early postoperative deep wound infection can be effectively cured with thorough debridement, continuous irrigation and drainage. For the late infections, however, the removal of implant is indicated to control the infection, but risk of loss of correction should be paid attention.