Cost analysis for patients with adult spinal deformity by surgical approach and technique: A systematic review of the literature.

Abstract

Adult spinal deformity (ASD) correction approaches span transforaminal lumbar interbody fusion (TLIF) and posterior-only (PO) fusion, with more complex options emerging such as combined anterior-posterior (AP) constructs, lateral lumbar interbody fusion (LLIF), and multilevel osteotomies. Given the substantially variable hospital costs associated with these diverse strategies, this systematic review quantifies and compares their economic impact to inform value-based decision-making in ASD surgery. We conducted a PROSPERO-registered systematic review and meta-analysis (CRD42025644391) of comparative studies to evaluate cost differences for various surgical interventions for ASD patients. We queried PubMed, CINAHL, MEDLINE, and Web of Science from inception through January 28th, 2025. Six observational studies of moderate quality (n = 7297; operative patients n = 7,095, 97.23 %) with a mean age 47.0 ± 5.3 years were included. Approaches included PO, LLIF, TLIF and combined AP. Osteotomies included grade 2 osteotomy and three-column osteotomies (3CO). One study found LLIF to have higher index hospitalization costs compared to TLIF ($65,937 vs. $50,945; p < 0.01) and higher 2-year cumulative costs ($70,847 vs. $53,657; p < 0.01), driven by increased OR expenses. Two studies found AP fusion to incur substantially higher index hospitalization costs compared to PO (range $84,329-$103,275 for AP vs. $58,789-$64,281 for PO; p ≤ 0.001), maintaining a significant cost gap at 2 years ($89,824 vs. $73,904; p = 0.011). However, the findings for quality-adjusted life years (QALY) were heterogenous for AP vs PO approaches. Osteotomy added an estimated $21,000 at 2 years, with 3-column osteotomy (3CO) having higher 90-day and 1-year costs than posterior-column osteotomy, but with higher complication and readmission rates. One study found that over 2 years, LLIF trended toward the lowest cost-per-QALY ($463,798) vs. grade-2 ($509,370) vs. 3CO ($518,406), with no significant differences. Complex ASD procedures observed higher index and two-year costs than TLIF or PO approaches, with cost-per-QALY ratios showing no clear benefit for higher-cost techniques. These findings are limited by heterogenous cost definitions and sparse utility data, warranting cautious interpretation and underscore the need for prospective, standardized cost-effectiveness studies with extended follow-up.