Lumbosacral Sagittal Parameters In Association To L5/S1 Intervertebral Disc Degeneration

BACKGROUND:Many studies have investigated the relationship between lumbosacral sagittal parameters and the disc degeneration diseases.However,the objects of these studies were mainly the patients with disc herniation,and parameters were measured on CT or X-ray.There are few publications reporting the relationship between lumbosacral sagittal parameters,which were measured on MRI,and patients who underwent surgery with disc extrusion.OBJECTIVE:To measure and compare the lumbosacral sagittal parameters in L5/S1 disc extrusion patients,and to investigate the relationship between the lumbosacral sagittal parameters(the major parameters are sacral table angle and lumbosacral angle)and L5/S1 disc degeneration diseases.METHODS:A total of 216 lumbago patients aged 18 to 35 years old were included from the Department of Orthopedics,Changhai Hospital Affiliated to The Second Military Medical University from September 2014 to September 2016 for retrospective analysis.According to with or without L5/S1 intervertebral disc protrusion,they were divided into no-disc herniation group(82 cases)and disc herniation group(134 cases).In the disc herniation group,33 cases with disc extrusion was selected as the disc extrusion group and the other 101 cases were abandoned according to the study purpose.The no-disc herniation group was subdivided into degeneration group(42 cases)and control group(40 cases)according to with or without L5/S1 degeneration.Angles of lumbar lordosis(LL),sacral table angle(STA)and lumbosacral angle(LSA)were measured.RESULTS AND CONCLUSION:Compared to the control group,the difference of LL was not significant in the degeneration group(P > 0.05),but STA and LSA were significantly reduced(P < 0.05).Compared with the no-disc herniation group,LL,STA and LSA were all decreased significantly in the disc extrusion group(P < 0.05).These results confirmed that LL in young adults with disc extrusion decreased significantly,however,in patients with disc degeneration,the decrease was not significant.The decrease in STA and LSA was strongly associated with disc degeneration diseases.STA and LSA are important parameters in the clinical evaluation of lumbosacral sagittal balance.