[Comparative study of lumbar spondylolisthesis treated by three different materials].

OBJECTIVE

To evluate the clinical outcome of autografts of ilium and interbody fusion cage or bone morphogenetic protein (BMP)/artificial bone material/ cage in treating lumbar spondylolisthesis.

METHODS

From January 1997 to January 2004,114 patients with lumbar spondylolisthesis were treated with posterior lumbar interbody fusion and pedicle screw fixation. There were 45 males and 69 females with an average age of 43 years ranging from 32 to 61 years. Of 114 patients, 85 cases were classified as degree I, 24 cases as degree II and 5 cases as degree III. The patients were divided into three groups according to the material used for interbody fusion: autografts of ilium (group A, n=42), interbody fusion cages (group B, n=36), and BMP/artificial bone material/ cage (group C, n=36). The clinical and radiographic results of the patients were compared among three groups.

RESULTS

All patients were followed from 13 to 30 months with an average of 15 months. There were no statistically significant differences in surgical time, blood loss, and disc space height of pre-operation (P>0.05) among three groups. No severe complication occurred in the three groups (P>0.05). The excellent and good rates in groups A, B and C were 81.0%, 80.6%, and 83.3% respectively, showing no statistically significant difference (P>0.05). The fusion rate of group C (97.0%) was significantly higher than those of group A (81.0%) and group B (83. 3%) (P<0.05) after 1 year of operation. And the average loss of disc space height in groups B and C was significantly lower than that in group A (P<0.05).

CONCLUSION

Higher fusion rate and lower loss of disc space height can be obtained in treating lumbar spondylolisthesis with BMP/ artificial bone materiel. It is an effective method in the treatment of spondylolisthesis.