Economic Impact of Revision Surgery for Proximal Junctional Failure After Adult Spinal Deformity Surgery: A Cost Analysis of 57 Operations in a 10-year Experience at a Major Deformity Center

STUDY DESIGN.Retrospective cohort analysis OBJECTIVE.Evaluate economic impact of revision surgery for proximal junctional failures (PJF) after thoracolumbar fusions for adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA.PJF after fusions for ASD is a major cause of disability. While clinical sequelae are described, PJF-revision operation costs are incompletely defined. METHODS.Consecutive adults who underwent thoracolumbar fusions for ASD (8/2003–1/2013) were evaluated. Inclusion criteriaconstruct from pelvis to L2 or above and minimum 6 months follow-up after the index ASD operation. Direct costs (surgical supplies/implants, room/care, pharmacy, services) were identified from medical billing data and calculated for index ASD operations and subsequent surgeries for PJF. Not included in direct cost data were indirect costs, charges, surgeon fees, or revision operations for indications other than PJF (i.e pseudarthrosis). Patients were compared based on the constructʼs upper-instrumented vertebra (UIV)upper thoracic (UTT1–6) vs. thoracolumbar junction (TLjxnT9-L2). RESULTS.Of 501 patients, 382 met inclusion criteria. Fifty-one patients [UT:14; TLjxn40 at index; average follow-up 32.6 months (6–92 months)] had revisions for PJF, which summed to $3.2 million total direct cost. Average direct cost of index operations for the cohort ($68,294) was significantly greater than PJF-revisions ($55,547). Compared to TLjxn, UT had a significantly higher average cost for index operations ($79,860 v.$65,868). However, PJF-revision cases were similar in average cost (UT:$60,103; TLjxn:$53,920; p = 0.09). Costs of PJF amounted to an additional 12.1% of the total index surgical cost in 382 patients. CONCLUSIONS.Revision operations for PJF after long thoracolumbar fusions for ASD are associated with an average direct cost of $55,547 per case. Revision costs for PJF are similar based on the index procedureʼs UIV level. At a major tertiary center over a 10-year period, PJF came at a very significant economic expense amounting to $3.2 million for 57 cases.Level of Evidence3