Purpose: We aimed to investigate the clinical performance of the constructs of double-door cervical laminoplasty with suture anchors by examining bony fusion at the hinges and lamina closure.
Methods: We retrospectively analysed computed tomography (CT) scans obtained preoperatively, immediately after the operation, and at follow-up of patients who underwent cervical laminoplasty using suture anchors. Hinge fracture, bony healing at the hinges, suture anchor failure, and the lamina angle (LA) were evaluated using CT. Lamina closure was defined as an LA <55° at follow-up.
Results: A total of 226 laminae and hinges from 37 patients were evaluated. CT scans immediately after the operation revealed that 13 laminae (5.8 %) were fractured, one of which collapsed into the spinal canal. Bony fusion at an average of 12.7 months after the operation was noted at 222 hinges (98.2 %), which was not affected by hinge fracture. One dislodged suture anchor was identified. The mean LAs were 34.4 ± 4.2° preoperatively, 87.4 ± 12.3° immediately after the operation, and 82.5 ± 12.9° at follow-up. At follow-up, four cases of lamina closure were identified (1.8 %), and the closure rate was significantly higher at C3 than at the other levels, although it was not affected by age, sex, causative disease, cervical alignment, suture anchor use, and hinge fracture.
Conclusions: The constructs of double-door cervical laminoplasty with suture anchors are stable with a high rate of fusion at the hinges. However, if the procedure is performed at C3, special modifications should be made to avoid lamina closure.
Keywords: Bony fusion; Cervical laminoplasty; Hinge fracture; Lamina closure; Lamina collapse; Suture anchor.