Orthopedics on the Rise: Billing Trends Reveal Changing Roles in Spine Surgery.

Background Spine surgery is a shared domain between neurosurgery and orthopedic surgery, yet the exact differences between the two specialties have not been fully elucidated. The aim of this study is to investigate the differences in procedural volume and the recent trends indicating shifting roles of these two specialties in spine surgery. Understanding these trends is critical for workforce planning, training, and interdisciplinary collaboration. Methods This study analyzed the publicly available Medicare Part B dataset containing procedure-level data from 2013 to 2022. After filtering, we analyzed data from 1,695 and 1,531 spine neurosurgeons and orthopedic surgeons, respectively. Results Spine neurosurgeons have a higher volume of new patient office visits than orthopedic spine surgeons (median per surgeon from 2013-22: 1015 (IQR: 793.5) vs. 948 (807.8), respectively) (p<0.01). However, orthopaedic spine surgeons have a higher volume of established patient visits (3736 [3561.5] vs. 1894.5 [1749.3]) (p<0.0001) and overall spinal procedure volumes (576 [562] vs. 480 [468.5]) (p<0.0001). Additionally, the majority of all spinal deformity and ALIF procedures are performed by orthopaedic surgeons (61.8% and 68.2%, respectively), but neurosurgeons are performing an increasing proportion of these procedures over time (p<0.0001). Conversely, although the majority (66.1%) of all cervical procedures are performed by neurosurgeons, orthopedic surgeons are performing an increasing proportion of these procedures (p<0.0001). Conclusions Although orthopedic spine surgeons are performing a higher volume of procedures than spine neurosurgeons, both specialties are slowly conducting a greater proportion of certain types of procedures that have been historically dominated by other specialties.