Cost and quality of life outcome analysis of postoperative infections after posterior lumbar decompression and fusion

Surgical site infections (SSI) following spine procedures are serious and costly complications that may reduce patient quality of life (QOL). Deep SSIs may also extend hospitalizations and require surgical debridement or antibiotic therapy, increasing costs to both patients and the healthcare system. Here we sought to evaluate the effect of deep SSI on care cost and QOL outcomes in patients undergoing posterior lumbar decompression and fusion. To do so we performed a retrospective study of patients undergoing lumbar decompression and fusion between 2008 and 2012. Patients experiencing postoperative deep SSI were matched to controls not experiencing a deep SSI. Included patients had prospectively-gathered QOL outcome measures collected preoperatively and at 6 months postoperatively. Health resource utilization was recorded from patient electronic medical records over the 6-month follow-up. Direct costs were estimated using Medicare national payment amounts. Indirect costs were based on missed work days and patient income. We found both cohorts experienced significant improvements in QOL scores following surgery, and there were no significant differences between the cohorts. The average total cost was significantly higher in the infected cohort compared to controls ($37,009 vs. $16,227; p < 0.0001). Compared to controls, patients experiencing deep SSI had greater costs in each of the following categories: hospitalizations (p < 0.01), office visits (p = 0.03), imaging (p < 0.01), and medications (p < 0.01). Among those experiencing deep SSI, there are significant increases in costs, with minimal long-term impact on QOL outcomes as compared with controls at the six-month follow-up.