RÉSUMÉ
<p><b>OBJECTIVE</b>To study the risk factors for deep surgical site infection after posterior thoracic and lumbar surgery.</p><p><b>METHODS</b>The medical data of the patients with deep surgical site infection after posterior thoracic and lumbar surgery from January 2008 to December 2013 were reviewed.For each case patient, 3 non-infected controls were randomly selected from the same database of all patients who underwent posterior thoracic and lumbar surgery.Patients who had diagnosis of spinal fractures, infection, tuberculosis, and tumor were excluded. The microbiology and related factors were collected and analyzed. T-test, χ2 test and Logistic analysis were used to analyze the data, respectively.</p><p><b>RESULTS</b>Ninety-nine cases were identified (infection group), 57 men and 42 women, average 54.5 years old, average body mass index 26.4 kg/m2. Fifty-five (55.6%) patients were identified with organisms, and the most common identified organism was Staphylococcus Aureus. Compared with the cases in the control group (44.4 g/L), the cases in the infection group (43.1 g/L) had a significant low albumin preoperatively (P=0.001). Multivariate Logistic analysis showed that obesity (OR=2.102, 95% CI=1.259-3.508), diabetes (OR=1.926, 95% CI=1.041-3.563), number of surgical levels≥3 (OR=1.985, 95% CI=1.130-3.486) were risk factors for this complication (P<0.05).</p><p><b>CONCLUSION</b>For deep surgical site infection after posterior thoracic and lumbar surgery, obesity, diabetes, preoperative low albumin and number of surgical levels≥3 are risk factors.</p>