OBJECTIVES

Minimally invasive spine surgery is increasingly performed in the United States and has been associated with favorable clinical and economic outcomes, including a potential for faster recovery. Most studies however evaluate single-cohort patients treated either with minimally invasive or open procedures, but do not provide head-to-head comparisons. This study was designed to evaluate matched cohorts treated either with minimally-invasive or open procedures for their perioperative outcomes.

METHODS

This study was conducted in Premier Healthcare Database. All patients with a posterior lumbar fusion procedure defined by ICD-10 procedure codes and a DRG=460 (spinal fusion, except cervical, without major complication or comorbidities), from 2015-Q1 2018 were identified and categorized as “Open” vs “MIS” based on procedure code. Demographic and comorbidities were collected for all patients. Patients from the MIS cohort were matched to the Open cohort using propensity score methodology (caliper: 0.2, method: nearest neighbor without replacement, model: logit, ratio: 4:1) on demographic, provider characteristic and comorbidities. Perioperative outcomes and costs were compared between groups using the Wilcoxon rank sum test.

RESULTS

796 MIS patients were matched to 2,388 open patients (matched age (Open: 61.68, SD: 13.02; MIS: 61.84, SD: 13.07), obesity rate (Open: 19.9%, MIS: 19.6%), Elixhauser index (Open: 2.17, SD: 1.74; MIS: 2.18, SD: 1.80)). Costs were greater in the MIS cohort ($29,180 (SD: $14,362) vs $27,616 (SD: $13,821), however hospital length of stay was shorter (2.94 (SD: 2.10) days in the MIS vs 3.14 (SD: 2.03) in the Open cohort (p = 0.0114)) and a non-significant trend of greater home discharges were observed in the MIS (68.0%) vs open cohort (64.5%). There were no differences in surgical complications.

CONCLUSIONS

In matched cohorts, patients with MIS in the hospital setting had lower length of stay and showed a trend of greater home discharge compared to patients with open surgery.