Improvements in Outcomes and Cost after Adult Spinal Deformity Corrective Surgery between 2008 and 2019.

Document Type


Publication Date


Publication Title

Spine (Phila Pa 1976)


washington; swedish; swedish neuro


STUDY DESIGN: Retrospective cohort.

OBJECTIVE: To assess whether patient outcomes and cost effectiveness of adult spinal deformity (ASD) surgery have improved over the past decade.

BACKGROUND: Surgery for ASD is an effective intervention, but one that is also associated with large initial healthcare expenditures. Changes in the cost profile for ASD surgery over the last decade has not been evaluated previously.

METHODS: ASD patients who received surgery between 2008-19 were included. ANCOVA was used to marginal means for outcome measures (complication rates, reoperations, HRQLs, total cost, utility gained, QALYs, cost efficiency [cost per QALY]) by year of initial surgery. Cost was calculated using the PearlDiver database and represented national averages of Medicare reimbursement for services within a 30-day window including length of stay and death differentiated by complication/comorbidity, revision, and surgical approach. Internal cost data was based on individual patient DRG codes, limiting revisions to those within 2Y of the initial surgery. Cost per QALY over the course of 2008-2019 were then calculated.

RESULTS: There were 1236 patients included. There was an overall decrease in rates of any complication (0.78 vs. 0.61), any reoperation (0.25 vs. 0.10), and minor complication (0.54 vs. 0.37) between 2009 and 2018 (all P

CONCLUSION: Between 2008 and 2019, rates of complications have decreased concurrently with improvements in patient reported outcomes, resulting in improved cost effectiveness according to national Medicare average and individual patient cost data. The value of ASD surgery has improved substantially over the course of the last decade.

Clinical Institute

Neurosciences (Brain & Spine)

Clinical Institute

Orthopedics & Sports Medicine