[Postlaminectomy vertebral lamina reconstruction and pedicle screw reduction and fixation for lumbar spondylolisthesis].

OBJECTIVE

To investigate the clinical effects of spinal canal decompression and pedicle screw reduction and fixation, and intervertebral bone grafting fusion for the treatment of lumbar spondylolisthesis associated with nerve compression symptoms.

METHODS

Postlaminectomy vertebral lamina reconstruction and pedicle screw reduction and fixation were performed in 32 patients with lumbar spondylolisthesis between August 2007 and August 2008. Of them, 26 patients were followed up for more than 1 year, including 16 males and 10 females who ranged in age from 55 to 76 years (mean 62.5 years). The course of disease was 2-10 years. All patients had low back pain, numbness and pain in one or both lower extremities and intermittent claudication symptoms. Radiograms showed L3, L4 or L5 anter-olisthesis of I to III degree. There were 18 cases of regressive olisthesis and 8 cases of spondylolysis. The clinical improvement, the vertebral reduction, the lamina fusion rate and canal stenosis state were observed and assessed.

RESULTS

The wounds healed well in all 26 cases without occurrence of significant complications. Clinical improvement was assessed according to the JOA lower back pain score scale. The mean preoperative score was 5.2 +/- 1.5, and 23.1 +/- 1.9 at 3 months after operation. The result was excellent in 20 cases, good in 5 cases, and fair in 1 case. The mean score on the last followed-up was 22.9 +/- 2.4, and the result was excellent in 19 cases, good in 5 cases, and fair in 2 cases. JOA score at 3 months after operation and that at the last followed-up were significantly different from that before operation (P = 0.00), and there was no significant difference between JOA score at 3 months after operation and that at the last followed-up (P > 0.05). Complete reduction was achieved in 17 degree I case and 5 degree II cases. Two degree II cases were improved to degree I, and 2 degree III cases were improved to degree I. Vertebral fusion was achieved 3 months after operation in 20 cases, and in all cases at the last followed-up. CT examination at the last follow-up showed no stenosis of the vertebral canal, dural sac and nerve root compression. The rebuilt vertebral lamina fused well. No graft bone absorption or failing fixation occurred.

CONCLUSION

Postlaminectomy reconstruction of the vertebral lamina and pedicle screw reduction and fixation can achieve satisfactory reduction and spine biomechanical stability in the treatment of lumbar spondylolisthesis, and can prevent latrogenic stenosis of the vertebral canal due to nerve oppression by the postoperative scar and nerve adhesion, with good early and medium-term curative effects. In addition, it provides a new way of thinking in the treatment of lumbar spondylolis-thesis.