The Study On The Relationship Between Modic Change And Disc Height Together With Lumbar Hyperosteogeny

Objective:The MRI signal change of cartilage endplate and under the endplate bone on the degenerated intervertebral disc were systematically described by Modic etc in1988,and Modic etc firstly presents the classification standard for the signal change,and researched on the histological change of all types.Modic change was the MRI signal change of cartilage endplate and under the endplate bone on the people with spine degeneration diseases.In recent years,with the deepening of the research to the Modic change by domestic and foreign scholars,the occurrence mechanism and outcome as well as the relationship between low back pain were emphasized gradually.The Modic change caused by biomechanical change,invasion of low toxic bacteria,biochemical changes of disc and genetic abnormalities, biomechanical change was the main reason.During lumbar degeneration,the height of lumbar intervertebral disc lost,vertebral body hyperostosis,lumbar facet joint and soft tissue relaxation lead to biomechanics change of spine.The degeneration of lumbar intervertebral disc will reduce compression resistance and viscoelastic,especially the spine was subject to surplus load,when the load beyond the acceptable pressure, the over load transfer to cartilage endplate and under the endplate bone,lead to the cartilage endplate injury,the Modic change appear on MRI.The degeneration of lumbar intervertebral disc will cause lumbar biomechanics redistribution,with atrophy of the lumbar disc,the pulling tension of fibrous ring to the vertebral body was increased,It would stimulate cartilage cells proliferation,formated osteophyte,the formation of osteophyte would increase contact area of vertebral bodies,remodeling the spine stability,and was beneficial to relax the load of endplate,reduced the incidence of Modic change.Low back pain(LBP) is a clinical syndrome with lumbosacral area pain or uncomfortable feel, with or without lower limps pain. The common cause of LBP are degenerative disc, inflammation of muscles and ligaments, irritating never root, hyperosteogeny, sacroiliitis,and the degeneration of lumbar disc in the main reason.Most researches show that Modic change was closely related the degeneration of lumbar disc.This study was to evaluate the relationship between Modic change and disc height together with lumbar hyperosteogeny and explore the role of Modic change in lumbar degeneration.Methods:The imaging data of60elderly patients with chronic low back pain in our hospital were analysed retrospectively,all patients were examinated by lumbar MRI and spine X-ray.We chose L1/L2～L5/S1disc as research object,and measured the height of the intervertebral disc front,middle and rear with calipers on lumbar MRI,the average of the three was the average height of the intervertebral disc,if the patients have lumbar scoliosis,the height of the disc were not equal,we should measure left,middle and right side of the disc,and added the height of front,middle and rear,the mean of the six height was the average hight of disc.The hyperostosis indexes of lumbar were measured on lumbar x ray,we measured the two osteophytes of connection and the two pedicle outer wall of connection,the ratio of the two connections was hyperostosis index,in our research we chose1.25as grouping criteria.We divided the enrolled patients into four groups in the basis of imaging changes. Group A1:The disc height lower than the eighty percent of average lumbar disc height but without severe lumbar hyperosteogeny; Group B2:Severe lumbar hyperosteogeny but without the disc height lower than the eighty percent of average lumbar disc height; Group A2:Both disc height lower than the eighty percent of average lumbar disc height and severe lumbar hyperosteogeny; Group B1:Neither disc height lower than the eighty percent of average lumbar disc height nor severe lumbar hyperosteogeny. Finally, the influence of disc height and vertebral bone hyperplasia on the incidence rate of Modic change was analyzed.Results:60patients, including22males and females38cases;the average age is68.4years,the course of the disease is5to27years.21cases of patients with lumbar disc herniation,19cases of patients with lumbar spinal stenosis,12cases of patients with lumbar spinal stenosis,One cases of patients with low back pain,7cases of patients with degenerative scoliosis.This research studied300discs,vertebral bodies and endplates,The incidence rate of group A1was54.33%.The incidence rate of group B2was29.67%. The incidence rate of group A2was34.81%. The incidence rate of group B1was16.89%. There was significant difference of lumbar endplate Modic change incidence rate among the four groups(P<0.05).The result of post hoc test showed that the incidence rate of Modic change in the group A1was higher than the other three groups(P<0.00714).There was no significant difference of Modic change incidence rate between group B2and group A2.Conclusion:The incidence rate of Modic change with disc collapse but without severe lumbar hyperosteogeny was high in elderly patients with chronic low back pain. There was no significant difference of Modic change incidence between patients with both disc collapse and severe lumbar hyperosteogeny and patients with severe lumbar hyperosteogeny but without disc collapse.