Robotic-Assisted Muscle-Preserving (RAMP) Decompression in the Thoracic and Lumbar Spine

Study Design. Cadaver validation study. Objective. To evaluate the accuracy and feasibility of a novel robotic-assisted muscle-preserving (RAMP) decompression technique in human cadavers. Summary of Background Data. Robotic-assisted (RA) platforms have shown their capability to advance the precision of spinal instrumentation, yet their integration into decompression procedures remains limited. Conventional decompression techniques often disrupt paraspinal musculature and stabilizing structures, underscoring the need for a controlled, tissue-sparing approach. Methods. Eight human cadavers underwent RAMP decompressions via a muscle-sparing approach, performing unilateral laminotomy with contralateral “over-the-top” decompression at ten levels (T8–L5) each, using a robotic bone removal instrument. Computed tomography (CT) was used for preoperative planning and radiographic evaluation of deviations at the posterior laminar bone removal site and the remaining anterior laminar cortex. Anterior cortical bone removal (ACBR) were classified as substantial if >3 mm ipsilaterally or >7.5 mm contralaterally. Results. A total of 80 levels underwent RAMP decompressions (40 thoracic, 40 lumbar). The median deviation from preplanned trajectories to postintervention CT was 0.7 mm (IQR 0.4–1.1 mm) at the posterior laminar bone removal site and 0.3 mm (IQR 0.1–0.6 mm) at the anterior laminar cortex bilaterally. ACBR occurred in 41.3% (33/80), with only one being unplanned and substantial (1.3%). Ipsilateral ACBR accounted for 4 (12.1%), with a median distance of 2.3 mm (IQR 2.1–3.4 mm). Contralateral ACBR were more frequent (29, 87.9%) with a median distance of 4.3 mm (IQR 2.7–5.8 mm). Conclusion. This study represents the first cadaveric validation of the novel RAMP decompression, demonstrating the feasibility and precision of this robotic technique for controlled laminar bone removal. This muscle-sparing approach may reduce morbidity while preserving long-term spinal stability, thereby supporting the expansion of robotic platforms into decompression procedures.