Neurophysiological monitoring during cervical spine surgeries: Longitudinal costs and outcomes

•Initially greater cervical spine surgery cost with IONM is offset the following year.•IONM was associated with reduced length of stay and fewer readmissions.•IONM was associated with lower nervous system complications and opioid prescription. Well-designed longitudinal studies assessing effectiveness of intraoperative neurophysiologic monitoring (IONM) are lacking. We investigate IONM effects on cost and administrative markers for health outcomes in the year after cervical spine surgery. We identified single-level cervical spine surgeries in commercial claims. We constructed linear regression models estimating the effect of IONM (controlling for patient demographics, pre-operative health, services during index admission) on total spending, neurological complications, readmissions, and outpatient opiate usage in the year following index surgery. IONM was associated with increased spending during index admission of $1229 (p = 0.001), but decreased spending post-discharge of $1615 (p = 0.010), for a net – $386 (p = 0.608) for the year after surgery. Shorter length of stay (0.116 days, p = 0.004) and fewer readmissions (20.5 per thousand, p = 0.036) accounted for some post-discharge savings. IONM was associated with decreased rates of nervous system complications (4/1000, p = 0.048) and post-discharge opiate use (17 prescriptions/1000, p = 0.050) in the year after index admission. IONM was associated with administrative markers suggesting improved health outcomes after cervical spine surgery without greater costs for the year. This study suggests IONM may have lasting health and cost benefits.