Abstract:

BACKGROUND: The anatomical design of the dynamic cervical implant (DCI) has similar biomechanical characteristics to the normal disc. The dynamic design has axial compliance and shock absorption. And the front teeth down fitting into the upper and lower vertebral bodies can get sufficient axial stability.
OBJECTIVE: To compare the change of related cervical biomechanical properties between DCI non-fusion and anterior decompression and fusion.
METHODS: A total of 6 adult human fresh cervical spinal specimens (C2-7) were randomly divided into A, B, C groups. Following intact specimens analysis, specimens in groups A, B, C were sequentially reconstructed at C5-6 segment with DCI, Cage and integrated anterior cervical plate cage benezech (PCB) implant. The range of movement (ROM) of the upper and lower cervical segments of C5-6 in 3 groups before and after surgery in biomechanical testing machine for 4 different physiological conditions and impose 2.0 N•m pure moment of couple was measured.
RESULTS AND CONCLUSION: After 3 kinds of fixation, the ROM of the upper and lower cervical segments of C5-6 increased more or less than the ROM of the intact specimens and showed better stability. And the ROM of cervical spine after fixation of DCI was similar to that of intact condition. There were no statistical significance between the ROM of the upper and lower cervical segments of C5-6 after 3 kinds of fixation (P > 0.05). There was no significant influence for the ROM of the upper and lower cervical segments. To some extent, the DCI diminished the axial stress and maintained the ROM of the cervical spine effectively.