Autonomous Spinal Robotic System for Transforaminal Lumbar Epidural Injections: A Proof of Concept of Study

Study Design: Phantom study Objective: The aim of our study is to demonstrate in a proof-of-concept model whether the use of a marker less autonomous robotic controlled injection delivery system will increase accuracy in the lumbar spine. Methods: Ideal transforaminal epidural injection trajectories (bilateral L2/3, L3/4, L4/5, L5/S1 and S1) were planned out on a virtual pre-operative planning software by 1 experienced provider. Twenty transforaminal epidural injections were administered in a lumbar spine phantom model, 10 using a freehand procedure, and 10 using a marker less autonomous spinal robotic system. Procedural accuracy, defined as the difference between pre-operative planning and actual post-operative needle tip distance (mm) and angular orientation (degrees), were assessed between the freehand and robotic procedures. Results: Procedural accuracy for robotically placed transforaminal epidural injections was significantly higher with the difference in pre- and post-operative needle tip distance being 20.1 (±5.0) mm in the freehand procedure and 11.4 (±3.9) mm in the robotically placed procedure (P <.001). Needle tip precision for the freehand technique was 15.6 mm (26.3 – 10.7) compared to 10.1 mm (16.3 – 6.1) for the robotic technique. Differences in needle angular orientation deviation were 5.6 (±3.3) degrees in the robotically placed procedure and 12.0 (±4.8) degrees in the freehand procedure (P =.003). Conclusion: The robotic system allowed for comparable placement of transforaminal epidural injections as a freehand technique by an experienced provider, with additional benefits of improved accuracy and precision.