Perioperative complications in primary intramedullary tumors of the spine in adults. A multicenter surveillance study of 307 patients from the German Spine Registry (DWG-Register).

Background: Intramedullary tumors represent only 10% of the spectrum of spinal tumors. Their management is not an easy task and depends essentially on the surgical resection which can be very challenging. The main aim of our study was to analyze the complication rate in intramedullary tumors as well as postoperative outcome after intramedullary tumor resection.

Methods: This was a retrospective analysis of data from the "DWG-Register" of patients who have undergone operative treatment for primary intramedullary tumors in 170 departments from January 2017 to May 2021. Since 2017, pre-, intra-, and postoperative data until demission from the hospital have been continually collected in the "DWG-Register" (a total of 179,955 in a period of 4 years in 170 departments).

Results: In total, 307 primary intramedullary tumors in the spine were identified; = 248 (Group 1) had nonoperative complications and = 59 had a complication related to the surgical procedure (Group 2); taking this in to account, die complication rate was 19.2%. The incidence of complications was: epidural hematoma = 5 (8.4%), paresis = 23 (38.9%), bowel/bladder dysfunction = 15 (25.4%), wound infection = 5 (8.4%), medullary injury = 2 (3.4%), cerebrospinal fluid (CSF) leakage = 15 (25.4%), and reintervention with hematoma, abscess, or surgical CSF leakage management in = 22 (37.2%). The risk of permanent morbidity increased with a thoracic level, masculine gender, a long clinical history, presence of epidural hemorrhage, blood transfusion, and surgery on a recurrent tumor.

Conclusion: Medullary tumors are a rare entity with a relative high complication rate (20%). Improvement of symptoms postoperative depends on several factors such as operated level, masculine gender, a long clinical history, presence of epidural hemorrhage, blood transfusion, and surgery on a recurrent tumor. In rare pathologies such as intramedullary tumors, the data from the DWG Register can be used to describe spinal surgery care in "real life."