Economics of less invasive spinal surgery: an analysis of hospital cost differences between open and minimally invasive instrumented spinal fusion procedures during the perioperative period

Abstract

Background: There is great debate about the costs and benefits of technology-driven medical interventions such as instrumented lumbar fusion. With most analyses using charge data, the actual costs incurred by medical institutions performing these procedures are not well understood. The object of the current study was to examine the differences in hospital operating costs between open and minimally invasive spine surgery (MIS) during the perioperative period.

Methods: Data were collected in the form of a prospective registry from a community hospital after specific Institutional Review Board approval was obtained. The analysis included consecutive adult patients being surgically treated for degenerative conditions of the lumbar spine, with either an MIS or open approach for two-level instrumented lumbar fusion. Patient outcomes and costs were collected for the perioperative period. Hospital operating costs were grouped by hospitalization/operative procedure, transfusions, reoperations, and residual events (health care interactions).

Results: One hundred and one open posterior lumbar interbody fusion (Open group) and 109 MIS patients were treated primarily for stenosis coupled with instability (39.6% and 59.6%, respectively). Mean total hospital costs were $27,055.53 for the Open group and $24,320.16 for the MIS group. This represents a statistically significant cost savings of $2,825.37 (10.4% [95% confidence interval: $522.51-$5,128.23]) when utilizing MIS over traditional Open techniques. Additionally, residual events, complications, and blood transfusions were significantly more frequent in the Open group, compared to the MIS group.

Conclusions/level of evidence: Utilizing minimally invasive techniques for instrumented spinal fusion results in decreased hospital operating costs compared to similar open procedures in the early perioperative period. Additionally, patient benefits of minimally invasive techniques include significantly less blood loss, shorter hospital stays, lower complication rate, and a lower number of residual events. Long-term outcome comparisons are needed to evaluate the efficacy of the two treatments.

Level of evidence: III CLINICAL RELEVANCE: This work represents a true cost-of-operating comparison between open and MIS approaches for lumbar spine fusion, which has relevance to surgeons, hospitals and payers in medical decision-making.

Keywords: MIS; complications; degenerative; lumbar; residual events.

Figure 1

Chart showing mean per patient costs by category for minimally invasive (MIS) and open groups. Note: *Denotes statistical significance, P < 0.05.

Figure 2

(A) Average open and minimally invasive (MIS) line item original procedure costs. (B) Average percent difference between open and minimally invasive (MIS) groups for line item index hospitalization costs. Note: *Denotes statistical significance, P < 0.05. Abbreviations: OR, open residual; PT/OT, physical therapy/occupational therapy; R&B, room and board (Hospital stay costs).

Figure 3

Number of residual events observed for open and minimally invasive (MIS) groups. Note: *Denotes statistical significance, P < 0.05. Abbreviations: ER, emergency room; DVT, deep venous thrombosis; PT, physical therapy.

Figure 4

(A) Average open and residual line-item costs for open and minimally invasive (MIS) groups. (B) Average percent difference between open and minimally invasive (MIS) groups for line item residual costs. Abbreviations: ICU, intensive care unit; OR, open residual; R&B, room and board (Hospital stay costs).