A few cost-effectiveness studies have used time-driven activity-based costing (TDABC) [Kaplan] in medicine [Au, Balakrishnan] and none in spine surgery. TDABC allows for detailed identification of costs during all phases of a patient's care cycle. While TDABC has been used in other industries, its use has been described only a few times in health care and rarely in the operative setting [Balakrishnan]. This may be due to the large amount of manpower necessary to collect TDABC data.