Cervical Spinolaminoplasty With Newly Designed Titanium Mini-Plates

Abstract

One of the complication of cervical laminoplasty is the restenosis of the opened laminae. Weakness of the screws placed on laminae may cause restenosis. Here, we describe a new technic 'spinolaminoplasty (Turkish Open-door laminoplasty)' with newly designed titanium mini plate that placed one side to lateral mass, and the other on spinous process to keep the laminae opened. Two different fixation materials were used for axial compression tests. One was Ultra high molecular weight polyethylene block with cervical vertebrae geometry and fresh ovine cervical vertebrae. In the first group, mini plates were fixed on laminae as in the conventional method described by Hirabayashi. In the second group, mini plates were fixed on spinous process to perform spinolaminoplasty with single and double screws. New fixation method with double screw provides 26% higher stiffness than the closest group, namely new fixation on polyethylene block. And new fixation method with double screw was exhibited significantly higher (P < 0:005) performance between the Ovine groups. As in the spinolaminoplasty technic fixing the mini plates to spinous process with longer screws instead of laminae, strengthens the system compared to the conventional method. This proves that rigidity of new construction model is more stable than the conventional method. Tight fixed laminae may prevent restenosis. Also applying the screw through spinous process instead of laminae may prevent the possible cord injuries.