Abstract:

BACKGROUND: Autogenous bone graft combined with cage has been widely used in lumbar interbody fusion by the use of vertebral pedicle screw fixation. But there is still lack of reports about autogenous morselized bone graft impaction with vertebral pedicle screw fixation concerning the clinical application and biomechanical research.
OBJECTIVE: To evaluate and compare the biomechanical stability properties of autogenous morselized bone graft impaction with vertebral pedicle screw fixation, cage with vertebral pedicle screw fixation, so as to provide theoretical basis and experiment guidance in clinical use of autogenous morselized bone graft impaction with vertebral pedicle screw fixation in PLIF.
METHODS: Resin embedding method and graded facetectomy and discectomy were made to prepare spinal instability models. Experimental group used autogenous morselized bone graft impaction with vertebral pedicle screw fixation; control group used cage with vertebral pedicle screw fixation. The three-dimensional motion of specimens was tested in intacted state, instability state and fusion state, which the flexion, extension, bilateral bending and axial rotation loading were applied to the specimens and the range of motion (ROM) were determined by the three-dimensional laser scanner.
RESULTS AND CONCLUSION: There was no significant difference in all stability indexes (ROM) between two groups in intact state (P > 0.05). Compared with the intact state, there was significant difference in all stability indexes in instable state between the two groups. After posterior lumbar interbody fusion, there was no significant difference in all stability indexes between two groups (P > 0.05). Both the autogenous morselized bone graft impaction with vertebral pedicle screw fixation and cage with vertebral pedicle screw fixation can improve the immediate biomechanical stability of the spine, and there is no statistical difference in spinal stability capacity between two groups.