• Sait NADER
  • Mustafa FİDAN
  • Adnan ATICI
  • Kemal YÜCESOY
  • Tansu MERTOL
  • M. Nuri ARDA

J Turk Spinal Surg 2000;11(4):38-42

Several disorders lead to craniovertebral junction instability, and require an occipitocervical fixation. İn cases in which screw is the choice of fixation, the types and places of the screws may affect the pull-out strength of the screvv. The aim of this study is to compare pull-out strength of different screws inserted into the occipital bone in the midline and paramedian regions in a monocortical and bicortical fashion. This biomechanical investigation revealed the strongest pull-out strength in the midline follovving a bicortical screvv insertion (521.14 ± 91.66 N), and the vveakest pull-out strength in the lateral position follovving a monocortical screvv insertion (271.85 ± 88.02). İt is concluded that the bicortical midline occipital screvv placement provide a biomechanical advantage.

Keywords: Biomechanics, Craniovertebral junction, Occiput, Screvv fixation