Figure 1.
Pre- and postoperative MRI of a 57-year-old man with multilevel cervical canal stenosis.
(A) Preoperative sagittal and (B) axial views of this MRI show the cervical spinal cord compressed by degenerative disk herniation at C3–4, C4–5 and C5–6 with five-level hypertrophic ligamentum flavum (arrows). (C) Postoperative sagittal and (D) axial MRI views 1 year after surgery demonstrate satisfactory decompression of the spinal cord. The dural sac has expanded significantly, and no restenosis is observed. MRI, magnetic resonance imaging.
Figure 2.
Reconstruction of elevated lamina.
(A) Autologous spinous process/graft plate construct. The spinous process is attached to the graft plate and secured by one mini-screw (arrow) through a pre-drilled center hole in the spinous process. (B) Fixation of elevated lamina. On the open side, the elevated lamina is fixed by the autologous spinous process/graft plate construct and mini-screws; on the hinge side, bone chips harvested from resected laminae are inserted into the residual gutter to facilitate bone union. (C) Measurement of elevated lamina. The height of lamina elevation is measured by a bone trial (arrow), which can aid in the selection of the appropriate Centerpiece plate and bone block.
Figure 3.
Intraoperative photograph of the hybrid decompression protocol.
Between C3 and C7, the C4 and C6 laminae are reconstructed and the C3, C5, and C7 laminae and ligamentum flavum are removed. The opened laminae are fixed with Centerpiece plates with shaped autologous spinous process (arrows). Four Centerpiece plates were used in this patient.
Figure 4.
One-year-postoperative radiographs.
(A) Anteroposterior and (B) lateral postoperative radiographs show the C3, C5, and C7 laminectomies and C4 and C6 laminoplasties with spinous process autograft Centerpiece plate fixation. (C), (D): Postoperative maximal flexion and extension lateral radiographs. No kyphosis or hardware failure is observed.
Figure 5.
Postoperative CT scan of a patient 6 months after surgery.
(A) Sagittal CT scan shows enlargement of the cervical spinal canal after posterior hybrid decompression. (B) Axial CT scan shows the reconstruction of a continuous and stable bony laminar arch. The hinge has completely healed with cortical bone on both its dorsal and ventral surfaces; the junction of bone block and host bone on the open side are bridged by cancellous bone.
Figure 6.
Cobb’s method for measuring cervical lordosis.
The cervical lordotic angle is measured according to Cobb’s method on a lateral neutral radiograph: the angle (c) is formed by the two lines perpendicular to the two lines parallel to the inferior endplates of the C2 and C7 vertebral bodies. When the C7 vertebra is not well visualized on lateral radiographs, the inferior plate of C6 is used.
Figure 7.
Range of motion of the cervical spine.
Angles a and b are created by a line parallel to the inferior aspect of the C2 vertebral body and a line parallel to that of the C7 vertebral body and were measured on maximal flexion and extension lateral radiographs. Total ROM value was obtained by adding these angles (ROM = angle a+angle b).
Table 1.
Demographic and primary clinical data of the patients.
Table 2.
Mean bone healing rates on the hinge and open side after surgery (%).
Table 3.
Postoperative spinal cord drift-back distance (mm) and cross-sectional area of the dural sac (mm2) at 3 months and 1 year after surgery (Mean± SD).