Abstract:

BACKGROUND: Many reports have shown different experiment results about the biomechanical test effects of the stress on the adjacent segments of vertebra with interbody fusion. The experiment results are very different of the stress characteristic on the adjacent segments of vertebra with interbody fusion under the conditions of loading control and shifting control test mode.
OBJECTIVE: To analyze adaptive variation of the space of intervertebral foramina C5/6 basing on graded-loading-force under forward flexion and rearward extended conditions under different conditions of intact cervical disc, cervical intervertebral discectomy, Bryan cervical disc prosthesis replacement, or anterior cervical discectomy and fusion using bone graft and plate fixation.
METHODS: The pathologic variational regulation of the space of bone intervertebral foramina C5/6 had been analyzed under different graded-loading-force (0.25, 0.50, 0.75, 1.00, 1.25 and 1.50 N•m) in forward flexion and rearward extended under different conditions of intact cervical disc, cervical intervertebral discectomy, Bryan cervical disc prosthesis replacement, or anterior cervical discectomy and fusion using bone graft and plate fixation.
RESULTS AND CONCLUSION: Under the different conditions of graded-loading-force in forward flexion and rearward extended conditions, on adult’s corpse cervical spine samples, the length diameter, superior width, inferior width and space of bone intervertebral foramina of C5/6 of the cervical intervertebral discectomy group was lower than that of the other groups (P < 0.05), the Bryan cervical disc prosthesis replacement group was higher than cervical intervertebral discectomy group (P < 0.05). The experiment results have shown that the average area data of space of bone intervertebral foramina C5/6 decreases after cervical intervertebral discectomy.