Research On Postoperative Fusion Effect Of The Quantity Of Intervertebral Bone Graft Material On Lumbar Intervertebral Fusion Internal Fixation

Purpose:Lumbar intervertebral fusion internal fixation is one of the most widely used lumbar fusion techniques in recent years, and the surgical approach to take posterior lumbar decompression, discectomy, pedicle internal fixation and intervertebral bone grafting + Cage implantation. This surgical method is mainly to release the spinal cord and nerve root compression through decompression, restore the normal sequence of the spine, and reconstruct the stability of the spine, so as to achieve the purpose of treatment of lumbar herniation, lumbar spinal stenosis or lumbar instability. This experiment selected patients with lumbar herniation, lumbar spinal stenosis or lumbar instability to conduct the posterior decompression intervertebral Cage implant + bone graft fusion and pedicle internal fixation, and different quantity of bone graft material were applied in the intraoperative intervertebral fusion. Conduct postoperative regular follow-up, by CT and clinical efficacy evaluation, compare the postoperative height change of intervertebral space, intervertebral fusion rate, and clinical symptoms improvement with different quantity of bone graft material, so as to study the impact on the quantity of bone graft material on intervertebral fusion success rate and postoperative effect.Methods:Selected 98 patients with lumbar herniation, lumbar spinal stenosis or lumbar instability who had the lumbar posterior surgery in our hospital from January 2011 to December 2013, all patients were giventhe posterior decompression, pedicle internal fixation and intervertebral bone grafting + spine cage implantation. The vertebral plate and spinous process bone obtained after decompression were selected for the intraoperative intervertebral bone grafting, remove soft tissue and small articular cartilage, cut them into bone particles with size of about 2mm, respectively implant 4ml, 5ml, and 6ml, implant the Cage after pressing, and press and fix the pedicle screw-rod fixation system. Based on the bone graft volume, divide the patients into group A, B, and C; the difference in sex, age, disease duration, lesion segments, intervertebral area, and other general information among the three groups was not statistically significant(P>0.05), and they were comparable. Respectively conduct regular follow-up for the three groups of patients at 1 month, 3 months, 6 months and 12 months after the surgery, and conduct CT scan and patient function score detection; by the comparison of the three groups of patients in clinical effect improvement, bone grafting fusion rate, height change of intervertebral space and assess the postoperative effect of different quantity of bone graft materialon intervertebral bone graft fusion.Results:All patients were followed up for 12 to 28 months with an average of 21 months. The difference in operative time, intraoperative blood loss, ambulation time and bone fusion time among the three groups was not statistically significant(P>0.05); Cage height difference among the three groups was not statistically significant(P>0.05). VAS scores of the three groups were improved significantly(P<0.05), but the difference among the three groups was not statistically significant(P>0.05); ODI scores of the three groups were improved significantly(P<0.05), but the difference among the three groups was not statistically significant(P>0.05); if the clinical results was evaluated according to Macnab criteria: the excellent rate in group A was 90.3%, group B was 91.0%,and group C was 91.2%,and the difference among the three groups was not statistically significant(P>0.05); at last follow-up, height change of intervertebral space of group A, B, and C were respectively(8.7±1.7),(9.8±1.7), and(10.1±1.8) mm, and the difference was not statistically significant(P>0.05). There were high intervertebral fusion rates among the three groups one year after the surgery, the fusion rates of group B and group C were significantly higher than that of group A, and the difference was statistically significant(P<0.05).Conclusion:For patients with degenerative lumbar spine disease who need surgical treatment, good clinical therapeutic effect can be obtained by selecting the posterior decompression pedicle screw internal fixation system with spine cage implantation. In this experiment, different quantity of bone graft material showed no significant difference in improving postoperative symptoms, but with the increase in quantity of bone graft material, postoperative radiographic evaluation results showed that the greater the quantity of bone graft material, the higher the early graft fusion rate, which decreased the intervertebral space height loss. Long-term follow-up showed there was non-fusion risk if the quantity of bone graft material was less than 5ml, so it was recommended that the quantity of intervertebral bone graft material should be up to 5ml or more.