Comparison Of Postoperative Effects Of Four Models Of Bone Graft Fusion In Posterior Lumbar Surgery For Lower Lumbar Degenerative Disease

Objective To investigate the postoperative effects and outcomes of patients with lower lumbar degenerative disease who underwent with posterior lumbar surgery performed with four bone graft fusion models, respectively. Thus providing more effective bone graft fusion procedure for clinicians.Methods Patients with lower lumbar degenerative disease who underwent with posterior lumbar surgery were recruited from Department of Orthopaedic Surgery, Affliated Chen Zhou No.1 People’s Hospital of University of South China from Jan 2010 to Jan 2014. Of the 478 patients, completed data of 80 patients were retrospectively analyed. All of operative treatments were used of pedicle-screw internal fixation and following bone graft fusion was performed with four models: lumbar intertransverse process bone graft fusion model(A group, n=20), lumbar intervertebral bone graft fusion model(B group, n=20), lumbar intervertebral simple bone graft fusion model(C group, n=20), and interbody fusion cages(D group, n=20). Data including operation time, intraoperative bleeding, postoperative drainage, blood loss during the surgery, postoperative hospital stay, Oswestry disability index(ODI) score, visual analogue score(VAS), intervertebral disc height, and bone graft fusion rate were collected and analysed for comparing of outcomes of patients in the four groups.Results(1) there were no significant differences of operation time, intraoperative bleeding, and postoperative drainage and the duration of hospital stay following surgical procedures among all treatment groups(p > 0.05).(2)All of groups had similar preoperative ODI scores( p > 0.05), All of groups had similar preoperative ODI scores at 12 months( p > 0.05). Notely, changes in ODI scores before surgery and 12 months after surgery in each group were significant( p < 0.001).(3)All of groups had similar preoperative VAS scores( p > 0.05), All of groups had similar preoperative VAS scores at 12 months( p > 0.05). Changes in VAS scores before surgery and 12 months after surgery in each group were significant( p < 0.001).(4)There were no significant differences in height of intervertebral disc of patients in the four groups who underwent the posterior lumbar surgery which examined by X-ray( p > 0.05). However, the mean height of intervertebral disc of patients in all of four groups, particularly group A and B(group A/B vs group C/D, p < 0.05), was decreased at 6 months after surgery. Furthermore, the mean height of intervertebral disc of patients in group A, B, and C was significantly decreased at 12 months after surgery( p < 0.05). Compared to group A, B, and C, patients in group D had higher intervertebral disc height at 12 months after surgery( p < 0.05).(5)Follow-up visits for all patients in the four groups were at 6, 12 months after the lumbar surgery. Follow-up visits for the fusion rate was at 6 months,group D was higher than group A and group B( p < 0.05); When 12 month follow-up group D fusion rate was higher than group A and group B( p < 0.05), group C fusion rate was higher than group A( p < 0.05).Bone graft fusion rate in group D was the highest during follow up period. Conclusions results of the study suggest:(1)Although the models of lumbar intertransverse process bone graft fusion and lumbar intervertebral bone graft fusion model for lower lumbar degenerative disease have several advantages in the two models including height of intervertebral disc, rate of bone graft fusion, and stability of the spine have worsen than the other models, that is lumbar intervertebral simple bone graft fusion model and interbody fusion cages.(2)The model of interbody fusion cages for lower lumbar de generative disease is a way of supporting fusion and has high bonegraft fusion rate. So interbody fusion cages model may be a ideal option for bone graft fusion in posterior lumbar surgery from our st udy.