Effects of Cervical Alignment and Rang of Motion Due to Different Kind of Laminectomy (LIN Guozhong, WANG Zhenyu, Peking University Third Hospital, Beijing China, 100191)

Object: To investigate the biomechanical effects of alignment and range of motion due to different kind of laminectomy.

Method: the patients underwent laminectomy were followed up. The preoperative and postoperative (at least 3 months) range of motion and alignment of cervical spine were measured. Comparative analysis was conducted according to different kind of laminectomy.

Result: A total of 153 patients were followed up for 3 to 96 months, which were divided into total laminectomy group (101 cases) and hemi-laminectomy group (52 cases). Patients with hemi-laminectomy had no cervical instability or deterioration of alignment. When ≥3 laminea were excised in total laminectomy, incidence of instability and deterioration of alignment significantly increased. With preoperative cervical sequence changes, high-stress position (C2 or C7) and small joint involved, the postoperative cervical alignment and rang of motion may be affected.

Conclusion: The hemi-laminectomy helps to maintain the stability of cervical spine. Patients with risk factors above should be long-term followed-up post-operatively. Multi-segmental laminectomy with facetectomy may need prophylactic fusion or internal fixation

[Key words]: spine, laminectomy, facet joint excision, stability, biomechanics