A new concept of motion preservation surgery of the cervical spine: PEEK rods for the posterior cervical region.

BACKGROUND Laminectomy may cause kyphotic postoperative deformity in the cervical region leading to segmental instability over time. Laminoplasty may be an alternative procedure to laminectomy, as it protects the spine against post-laminectomy kyphosis; however, similar to laminectomy, laminoplasty may cause sagittal plane deformities by destructing or weakening the dorsal tension band. OBJECTIVE Using finite element analysis (FE), we attempted to determine whether a posterior motion preservation system (PEEK posterior rod system concept) could overcome the postoperative complications of laminectomy and laminoplasty and eliminate the side effects of rigid posterior stabilization in the cervical region. METHODS We compared PEEK rods in four different diameters with a titanium rod for posterior cervical fixation. The present study may lead to motion preservation systems of the cervical vertebra. RESULTS When PEEK rod is compared with titanium rod, considerable increase in range of motion is observed. CONCLUSIONS PEEK rod-lateral mass screw instrumentation systems may be useful in motion preservation surgery of the posterior cervical region.