Time is money: a systematic review of time directed activity based costing in spine surgery

INTRODUCTION: Healthcare costs in the USA have increased without corresponding improvements in patient outcomes, prompting calls for value-based reimbursement models. Accurate cost measurement per episode of care is essential to this approach. Traditional methods, such as cost-to-charge ratio (CCR), lack precision. Time-driven activity-based costing (TDABC), which assigns costs based on time spent per activity, offers a more accurate alternative. This review evaluates TDABC use in spine surgery and its potential to enhance cost transparency and efficiency. EVIDENCE ACQUISITION: This systematic review followed PRISMA guidelines. A literature search was performed for studies published between 1996 and 2025 using terms related to costing strategies and spine surgery. Included studies applied TDABC in cost analysis; non-English and commentary articles were excluded. Extracted data included costing methodologies, cost categories, and study purpose. Bias was assessed using the Newcastle-Ottawa scale. EVIDENCE SYNTHESIS: Twelve studies including 6143 patients were analyzed, covering procedures such as ACDF, lumbar laminectomy, and microdiscectomy. Reported costs for single-level ACDF ranged from $ 6776 to $ 27,558. Most studies focused on intraoperative costs, though some included full care episodes. TDABC identified cost differences tied to factors such as surgeon experience and BMI. Personnel time, hospital stay, and postoperative visits were common cost drivers. CONCLUSIONS: TDABC offers a more granular and accurate method for analyzing spine surgery costs. However, variation in methodology across studies limits comparability. Standardized protocols and direct comparisons with traditional costing methods are needed to fully leverage TDABC's potential for improving cost management and care efficiency.