Can We Justify It? Trends in the Utilization of Spinal Fusions and Associated Reimbursement

Previous reports have suggested an increasing rate of utilization of spinal fusions, but contemporary data have not been analyzed, and there has been little investigation of putative drivers of increased utilization.

To investigate whether there is an ongoing trend of increased utilization of spinal fusions in recent data, and if there may be associations with an increasing proportion of elderly in the population, changing patterns of payer-types, and changing reimbursement rates.

We analyze 7.1 million cases from the National Inpatient Sample between 1998 and 2014. We measure annual utilization per 100 000 persons and conduct trend analyses with subgroup analysis of the senior (65 + ) population. Spine surgery utilization is compared with nonspine surgical procedures (coronary artery bypass grafting, hernia repair, hip, and knee replacement). We assess trends in charges, payer type, Medicare reimbursement rates, and hospital type.

There was an 88% increase in the utilization rate of spinal fusion procedures from 1998 to 2014 (from 74 to 139 cases per 100 000 persons) with a significant upward trend (P < .001) that persisted in the 65 + subgroup (P < .001). An increasing proportion of spinal fusions is paid for by public payers, but per-procedure reimbursement for spinal fusions by Medicare has decreased recently (5% reduction from 2014 to 2016).

Utilization of spinal fusions continues to increase and is not explained by increased proportion of elderly in the population, increased utilization of surgeries across specialties, or increased Medicare reimbursement. In fact, increased utilization of spinal fusions temporally correlated with decreasing per-procedure Medicare reimbursement.