Preventive measures for axial symptoms following cervical laminoplasty.

We have modified the operative procedure of laminoplasty and changed the postoperative therapy since 1997. In the modified group, several modifications were incorporated. The open door type of cervical en bloc laminoplasty was performed. 1) Bone grafts in the open gap were placed at three levels only. 2) Bone grafting in the hinged side was not performed. 3) The neck collar was worn for only 1 month. 4) The doctors explained the importance of the neck muscle and advised patients to perform early exercise of the posterior neck muscle. The patients who had the original operation and postoperative therapy served as the control (control group). The original operation and postoperative therapy were as follows: Bone grafts from dissected spinous processes were put in the opened laminae and fixed with braided wires or nylon threads. Bone grafts in the open gap were placed to extend from three to five levels. Bone chips were also placed in the hinged side. The orthosis was applied for up to 1 months after surgery, and a neck collar was recommended for 1 additional month. Postoperative neurologic recovery and axial symptoms after cervical laminoplasty were compared between the two groups. There was no statistical difference in postoperative neurologic recovery. However, the incidence of axial symptoms was much lower in the modified group compared with the control group. Radiologic examination showed that postoperative range of motion of the cervical spine in the modified group was significantly well preserved and the number of postoperative fused laminae in the modified group was less than that in the control group. Based on these results, we concluded that the modified method is beneficial for the postoperative status of cervical laminoplasty patients.