[Treatment of intraspinal benign tumors in upper cervical vertebrae by modified recapping laminoplasty]

To evaluate the effectiveness of modified recapping laminoplasty preserving the continuity of supraspinous ligament in the treatment of intraspinal benign tumors in upper cervical vertebrae and its influence on the stability of the cervical vertebrae.

The clinical data of 13 patients with intraspinal benign tumors in upper cervical vertebrae treated between January 2012 and January 2021 were retrospectively analyzed. There were 5 males and 8 females, the age ranged from 21 to 78 years, with an average of 47.3 years. The disease duration ranged from 6 to 53 months, with an average of 32.5 months. The tumors located between C ₁ and C ₂. Postoperative pathology showed 6 cases of schwannoma, 3 cases of meningioma, 1 case of gangliocytoma, 2 cases of neurofibroma, and 1 case of hemangioblastoma. During operation the continuity of the supraspinal ligament were retained, the lamina ligament complex was lifted to expose the spinal canal via the approach of the outer edge of the bilateral lamina, and the lamina was fixed after the resection of the intraspinal tumors. Before and after operation, the atlantodental interval (ADI) was measured on three-dimensional CT; the effectiveness was evaluated by Japanese Orthopaedic Association (JOA) score, the neck dysfunction index (NDI) was used to evaluate the cervical function, and the total rotation of the cervical spine was recorded.

The operation time was 117-226 minutes (mean, 127.3 minutes); the intraoperative blood loss was 190-890 mL (mean, 227.8 mL). The tumors were completely removed in all patients. There was no vertebral artery injury, aggravation of neurological dysfunction, epidural hematoma, infection, or other related complications. Two patients occurred cerebrospinal fluid leakage after operation, which were healed through electrolyte supplement and local pressure treatment of incision. All the patients were followed up 14-37 months, with an average of 16.9 months. Imaging examination showed no recurrence of tumor, displacement of vertebral lamina, loosening and displacement of internal fixator, and secondary reduction of vertebral canal volume. At last follow-up, JOA score significantly improved when compared with preoperative scores ( P<0.05). Among them, 8 cases were excellent, 3 cases were good, and 2 cases were medium, with an excellent and good rate was 84.6%. There was no significant difference in ADI, total rotation of the cervical spine, and NDI between pre- and post-operation ( P>0.05).

The treatment of intraspinal benign tumors in upper cervical vertebrae with modified recapping laminoplasty preserving the continuity of the supraspinous ligament can restore the normal anatomical structure of the spinal canal and maintain the stability of the cervical spine.