Investigate The Morphological Change Of Lumber Multifidus With Lumbar Disc Herniation By MRI

PURPOSE:Taking patients with unilateral symptoms of radiculopathy caused by lumbar disc herniation at the L4-5 level as study objects.The morphological changes of the lumbar multifidus were observed by MRI.To investigate the relationship between lumbar multifidus morphological changes and lumbar disc herniation.To investigate the possibility of locating the position of lumbar disc herniation by observing the morphological changes of lumbar multifidus.METHODS:In total,93 patients with unilateral symptoms of radiculopathy caused by lumbar disc herniation at the L4-5 level were enrolled.The cross-sectional area(CSA)and the perpendicular distance between lumbar multifidus and lamina(MLD)were surveyed by MRI T2 WI at L3/4,L4/5,and L5/S1 levels.The CSA and MLD of the lumbar multifidus were measured on the normal side and the affected side.Subjects were divided by symptom duration: 1–30 days(group A),31–90 days(group B),and>90 days(group C).There were 17 cases in group A,22 in group B,and 54 in group C.Subjects were divided by the position relationship between the herniated nucleus pulpous and the nerve root: 18 cases L4 nerve root was compressed(L4 nerve root group),75 cases L5 nerve root was compressed(L5 nerve root group).Nerve compression was evaluated according to Pfirrmann and showed a severity of II in 8 cases,III in 38 cases,and IV in 47 cases.First,lumbar multifidus' CSA and MLD were compared between the normal side and the affected side,and then lumbar multifidus' CSA and MLD were compared in each group.RESULTS:1.In group A,the median lumbar multifidus' CSA was not significantly different between the diseased side and the normal side(P>0.05).In groups B and C,the normal side's lumbar multifidus CSA was significantly different form the affected side(P<0.05).In groups A,B,and C,the normal side's MLD was significantly different form the affected side(P<0.05).The MLD increased on the diseased side with the increase of lumbar disc herniation symptom duration.2.Lumbar multifidus CSA or MLD was no significantly difference between L4 nerve root group and L5 nerve root group on the normal side or the affected side(P>0.05).3.The median lumbar multifidus' CSA and MLD on the normal side and the affected side were no significantly different between nerve compression degrees(P>0.05).CONCLUSIONS:On the affected side lumbar multifidus' morphological changes correlates with the duration of lumbar disc herniation.Lumbar multifidus' morphological changes were irrelevant to degree of nerve root compression and the position relationship between the herniated nucleus pulpous and the nerve root.We can't accurately locate the position of the nucleus pulpous by observing the lumbar multifidus' morphological changes.