Advance in screws fixation in posterior route pedicle on lower cervical spine

With the continuously exploration, in recent years, further understanding of anatomical characteristics of the cervical pedicle brings great breakthrough in cervical pedicle screw implantation. In addition, pedicle screw implantation in cervical spine is considered as a technique with high safety and reliability, which can be widely used in cervical trauma fracture, cervical instability, degenerative, inflammatory, benign or malignant tumor, deformity and other neck diseases. Because of the tremendous differences between upper cervical spine (C1, C2) and lower cervical spine (C3-7) in anatomical morphology, cervical pedicle screw implantation in C1 and C2 differs from in lower cervical spine. Due to the similar structure of C3-7, pedicle screw implantation methods are based on the same principle and sharing a few points in common. The pedicle screw technique can be classified in two groups according to the practice methods: navigation technology and manual placement of cervical pedicle screw. Navigation nailing is considered as reliable, easy handing, and with clear operative vision, however, with disadvantages as complex procedures, highly cost operation equipment, and risk in navigation draft. Therefore, manual placement of pedicle screw is more reasonable and practical comparing with the former. In this study, it analyzed anatomical characteristics of lower cervical pedicle and the measurement of pedicle structure, discussed technique of manual placement of pedicle screw in lower cervical spine and biomechanical study of pedicle screw, and summed up the comparison of the advantages and disadvantages of current representative manual placement technology.