Résumé
BACKGROUND:Many present scholars do a large number of researches on anatomical structure in the thoracic costotransverse binding region so as to seek a safe pathway of screw entrance besides posterior thoracic approach outside pedicle, but their conclusions are controversial. OBJECTIVE: To measure the anatomical and radiological structures of costotransverse groove and to explore the safe pathway of screw implantationvia posterior thoracic vertebra outside pedicle of vertebral arch. METHODS:Eight embalmed adult cadaveric thoracic spines were harvested with the medial 5.0-6.0 cm of rib. Intercostal soft issue and parietal pleura were left intact. Al nonstructural soft issue was removed. Specimens were scanned with CT, and three-dimensional reconstruction was performed. The angles of the costotransverse groove were obtained. Anatomical analysis was performed in specimens. The distance from the superior limit of the rib superiorly to the superior limit of adjacent transverse process and the distance from the inferior limit of the rib inferiorly to the inferior limit of adjacent transverse process were measured. RESULTS AND CONCLUSION:There exists a costotransverse groove between rib and transverse process. Both distance from the superior limit of the rib superiorly to the superior limit of adjacent transverse process and the distance from the inferior limit of the rib inferiorly to the inferior limit of adjacent transverse process of T6-10 were significantly larger than other levels (P < 0.05). The costotransverse groove was most obvious at T6-10 segments. Results verified that adult costotransverse groove directed to vertebra, and provided a new idea for the pathway of screw implantationvia posterior thoracic vertebra outside pedicle.
Résumé
Objective: To biomechanically compare the initial stability of two cervical interbody cages with different surfaces on human specimens.Methods: Flexibility of twenty-three cervical motion segments (two groups) were tested in axial rotation, flexion/extension and lateral bending, intact and after implantation of a cervical interbody fusion cage (SynCage-C Curved, SynCage-C Wedged). An implant pullout concluded testing. Changes in range of motion (ROM) were analyzed.Results: Both cages were effective at reducing ROM in all directions, with no significant differences in effacency. The pullout force differed significantly between the two cages, the SynCage Curved being higher. Conclusion: Differences of surfaces of the two cages don't affect their initial stability. The cage with a better contoured surface had a higher pullout force.