Risk factors for surgical site infection in thoracic and lumbosacral spine surgery: retrospective study results

Objective. To specify risk factors for the development of surgical site infection in patients operated on for injuries and degenerative diseases of the thoracic and lumbosacral spine through the posterior median approach. Material and Methods. The study included formalized case histories of 415 patients (207 men, 208 women) who were operated on for degenerative diseases (n = 385) or unstable injuries (n = 30) of the spine. The average age of patients was 47 ± 18 years. Out of them, 230 patients had concomitant chronic diseases requiring constant drug treatment. Before statistical processing, the data obtained in the study were classified according to a generally accepted method to determine the possibility of using different statistical methods when comparing groups. The patients were divided into two groups: Group I included patients with pyoinflammatory complications, and Group II – without pyoinflammatory complications. Results. It was revealed that the following factors significantly affect the development of postoperative wound suppuration: the use of metal fixation, external drainage of the wound for more than four days, the use of monocoagulation from the level of subcutaneous fat, the installation of a retractor for a period of more than 1 hour, blood loss of more than 300 ml, leaving absorbable hemostatic materials in the wound, suturing of muscles in the area of laminectomy, and applying intradermal (cosmetic) sutures. Patient age, preoperative bed day number, skin isolation technique (or lack thereof), duration of surgery, and surgeon experience do not affect the risk of the surgical site infection. Conclusion. Despite the fact that most of the identified risk factors for postoperative wound suppuration are reduced to more complex and prolonged intervention which is more difficult for a patient to tolerate, some of the identified risk factors are potentially removable.