Comparative Study on Short Term Efficacy between Dynamic Neutralization System and Posterior Intervertebral Fusion for Degenerative Spinal Stenosis

Objective: To compare short term efficacy between dynamic neutralization system and posterior interior intervertebral fusion for degenerative spinal stenosis. Methods: 70 Patients with intervertebral disc herniation with spinal canal stenosis or not were randomly divided into dynesys group(n=38) and posterior intervertebral fusion group(n=32), the former group was applied with vertebral decompression and dynesys internal fixation, and the latter was given decompression and posterior intervertebral fusion, follow-up for 24 months, and postoperative function recovery, intervertebral space height, motion range and degeneration of adjacent segment were compared between the two groups. Results: 1 All patients were successfully operated and followed up for 24 months. At the end of follow-up, ODI and VAS scores of patients in two groups were significantly decreased compared with preoperation(P0.05), but there was no significant difference between the ODI score and VAS score(P0.05). 2 The fixed segment spaces of the two groups were significantly increased compared with preoperation(P0.05), Range of motion of L4-5 segment and L5-S1 segment of dynesys group was significantly decreased(P0.05). However, the fusion segment of Fusion group fixed good and there was no activity. 3Cranial adjacent segment activity of prepost treatment had no obvious change in dynesys group, cranial adjacent segment activity of fusion group increased significantly compared with preoperation(t=2.286, P=0.026),the difference was statistically significant between the two groups(t=3.125, p=0.003). 4At the end of follow-up, One case(2.6%) in dynesys group had one screw loosening at S1 segment, no other adjacent segment was found degeneration; fusion group had four cases(12.5%) hadⅠ-Ⅱ degree adjacent segment degeneration,The difference was significant between the two groups(P=0.039). Conclusions: The short term effect of dynesys dynamic fixation operation and traditional posterior interior intervertebral fusion for degenerative spinal whose short-term efficacy postoperativly were similar, but adverse influence of the former on adjacent segment activity is less than fusion method.