Comparison of the outcomes between muscle-pedicle open-door laminoplasty and the traditional approach of lamina replantation with internal fixation in the treatment of lumbar subdural extramedullary tumor

English Keywords:Subdural extramedullary tumor  Laminoplasty  Muscle pedicle  Replantation

English Abstract:

  【Abstract】 Objectives: To compare and analyze the clinical efficacy of muscle-pedicle open-door laminoplasty and traditional approach of lamina replantation with internal fixation in treating lumbar subdural extramedullary tumor. Methods: Retrospective analysis of the clinical data of 15 patients with lumbar subdural extramedullary tumor treated in the Department of Spine Surgery in the Shinan District of the Affiliated Hospital of Qingdao University from March 2016 to December 2018 was conducted. According to surgical methods, the patients were divided into two groups: group A of 7 patients receiving traditional approach of lamina replantation with internal fixation and group B of 8 patients receiving muscle-pedicle open-door laminoplasty. There was no significant difference in general data such as gender, age and tumor type between the two groups(P＞0.05). The operative time, intraoperative blood loss, number of replanted or plastic laminae, length of hospitalization, inpatient cost, postoperative complications, and recurrence of tumor of the patients were recorded. The visual analog scale(VAS) and Oswestry disability index(ODI) were assessed at preoperation, 1 week and 6 months after the operation, and the clinical efficacy was compared between the two groups. CT scans were performed to evaluate bone resorption and bone fusion at 7 days, 3 months and 6 months postoperatively. Results: Both approaches provided sufficient exposure and complete resection of the tumor. Group A was followed up for 8.1±2.9 months and group B for 8.6±3.0 months, and no tumor recurrence occurred during the follow-up period. There was no statistically significant difference in operative time, intraoperative blood loss, number of replanted or plastic laminae, length of hospitalization between the two groups(P>0.05). The operative time and inpatient cost in group B were less than those in group A(P<0.05). The VAS scores and ODI of patients in both groups at 7d and 6 months after operation were significantly lower than those before operation(P<0.05), while there was no significant difference between the two groups(P>0.05). One patient of group B had big toe hyperesthesia which disappeared in a week, and one patient of group A occurred cerebrospinal fluid leakage which was cured after symptomatic treatment. At 6 months after operation, the replanted laminae of all the 7 patients in group A were fused incompletely, on the contrary to complete bone fusion on the muscle-pedicle side of the lamina of the eight patients in group B; and postoperative bone resorption was observed in all 7 patients of group A, while none was found in group B. Conclusions: Both muscle-pedicle open-door laminoplasty and traditional approach of lamina replantation with internal fixation can achieve good clinical results in the treatment of subdural extramedullary tumor. Muscle-pedicle open-door laminoplasty features less operative time and less inpatient cost, which also has some advantages in avoiding bone necrosis, bone resorption, and accelerating bone fusion.