Distribution of Modic changes of lumbar endplate in middle-elderly population with low back pain and its relationship with lumbar instability

Objectives: To investigate the distribution of Modic changes of lumbar endplate in middle-elderly population with low back pain,and its relationship with lumbar instability.Methods: 430 patients(210 males and 220 females) aged more than 40 years old(range,40-73 years) in our hospital from March 2007 to December 2011 were reviewed retrospectively.The incidence,type and distribution of Modic changes were reviewed.All patients were divided into lumbar stable group and unstable group,and the relationship between Modic changes and lumbar instability was analyzed.The patients with lumbar stability were further divided into two subgroups based on lumbar curvature.The correlation between Modic changes and lumbar curvature was analyzed.Results: Among 2150 intervertebral discs of 430 patients,154(7.16%) discs of 124(28.84%) cases were involved in Modic changes;34(1.58%) discs were diagnosed as type Ⅰ;100(4.65%) discs as type Ⅱ;20(0.93%) discs as type Ⅲ;the lesions involved L2/3(0.65%),L3/4(1.12%),L4/5(2.32%) and L5/S1(3.07%).The location of Modic changes was noted in 154 levels(52 superior end plate,41 inferior end plate,61 both),and 79 sited anteriorly,31 sited posteriorly,44 sited both anteriorly and posteriorly.The incidence of Modic changes in unstable group and stable group was 36.68% and 19.90% respectively,which showed significant difference(P0.05).The incidence of lumbar instability in Modic Ⅰ,Ⅱ,Ⅲ type was 82.35%,69.44% and 33.33% respectively,and there were significant differences among them(P0.05).The incidence of Modic changes in normal lumbar curvature group and abnormal curvature group was 11.11% and 23.91% respectively,which showed significant differences between both groups(P0.05).Conclusions: Modic changes of lumbar endplate in middle-elderly population correlate with lumbar instability and lumbar curvature,and Modic Ⅰ type change is related to lumbar instability greatly,while Modic Ⅱ type change is the most prevalent,which almost sites in L4/5 and L5/S1.