Abstract
PURPOSE: Minimally invasive surgery (MIS) of the spine has been associated with favorable outcomes compared to open surgery. This study evaluated matched cohorts treated with MIS versus open posterior lumbar fusion for costs, payments, healthcare utilization and outcomes. PATIENTS AND METHODS: This study used the Premier Healthcare and IBM(®) MarketScan(®) Commercial and Medicare Databases. Patients with posterior lumbar fusion from 2015 to 2018 were identified and categorized as "Open" or "MIS". Cohorts were matched on patient and provider characteristics. Perioperative complications, hospital costs, healthcare utilization and post-operative outcomes and payments to providers were analyzed. Statistical significance was evaluated using T-tests and chi-square tests. RESULTS: After matching, 2,388 Open and 796 MIS from PHD, and 415 Open and 83 MIS from MarketScan were included. Statistically significant differences between MIS versus Open were found for index hospital costs, $29,181 (SD: $14,363) versus $27,616 (SD: $13,822), p=0.01; length of stay, 2.94 (SD: 2.10) versus 3.15 (SD: 2.03) days, p=0.01; perioperative urinary tract infection, 1.01% and 2.09% (p=0.05); and 30-day risk of hematoma/hemorrhage, 19.28% versus 8.43%, p=0.02. There were observed, but statistically non-significant differences in additional perioperative or post-operative complications, home discharge, 90-day all-cause and spine-related readmission, and 90-day post-operative payments. CONCLUSION: Compared to Open, patients that underwent MIS had statistically significant lower length of stay, lower perioperative UTI, greater hospital costs, and higher 30-day risk of hematoma/hemorrhage. The differences observed in post-operative complications and payments and readmissions warrant further investigation in larger matched cohorts.