ABSTRACT
Objective To compare the short‐term clinical effects of single segment and two segments of Dynesys dynamic in‐ternal fixation system for treating lumbar degenerative disease .Methods 40 cases of degenerative lumbar disease treated by the Dynesys dynamic fixation system combined with posterior approach decompression from 2009 July to March 2012 were selected and performed the evaluation on the clinical effects by the waist and leg pain visual analogue scale (VAS) ,the Oswestry disability index (ODI) and the orthopaedic spinal association of North America (NASS) index .The imaging method was used to observe the mobili‐ty of operative segment and proximal adjacent segment and the degenerative change of intervertebral height .Results All of the 40 cases were followed up .The VAS score and ODI score at postoperative 3 months and last follow‐up were significantly decreased when compared with the pre‐operative scores (P 0 .05) .The NASS index showed no statistically significant difference in the postoperative effect satisfaction between the two groups (P>0 .05);there was no statistically significant difference in the variation of the intervertebral height between before operation and at the last follow‐up (P>0 .05) .There was statistically significant difference in the motility of proximal adjacent segment at the last follow‐up between the two groups (P<0 .05);but comparing the motility of proximal adjacent segment between the last follow‐up and pre‐operation , only the single segment group showed statistically significant difference (P< 0 .05) .Conclusion The Dynesys dynamic fixation system combined with posterior approach decompression operation has good clinical effect in the treatment of lumbar degenerative disease .Meanwhile ,the single segment method has more significant effect on the motility of proximal adjacent segment than the double segments method .