Spinal Intradural Extramedullary Tumors: A Retrospective Analysis on Ten-Years’ Experience of Minimally Invasive Surgery and a Comparison with the Open Approach

Abstract

Spinal intradural extramedullary (ID-EM) tumors are pathologies widely treated through a classical open approach. However, minimally invasive surgery is gaining traction as a comparable treatment option because it carries less morbidity and may reduce healthcare costs. This study aimed to compare the clinical and functional outcomes of open versus minimally invasive approaches for patients with ID-EM tumors. We performed a retrospective analysis on prospectively collected data from patients with ID-EM tumors submitted to surgery. Baseline features and operative variables were compared, including surgery duration and estimated blood loss (EBL). Postoperative data covered tumor histology, length of stay (LOS), complication(s), and neurological status (Medical Research Council (MRC) scale) at the last follow-up. In total, 46 patients were included: 30 (65.2%) operated through an open approach and 16 (34.8%) through a minimally invasive surgical (MIS) approach. The predominant histology type was schwannomas (43.5%). Lesions more frequently affected the lumbar spine (34.8%). The tumor dimensions were similar in both cohorts. The minimally invasive approach was on average 76.7 min faster and correlated positively with less EBL (140 mL less than that of the open approach). Patients in the MIS group had shorter LOSs (5.63 days vs. 17.27 days) and had fewer postoperative complications. No significant difference in functional outcome was found. MIS is as effective as the traditional approach in achieving comparable functional outcomes, with advantages such as shorter surgery durations, less blood loss, and shorter hospital LOSs.