The Effect Of Modic Changes On The Treatment Of Lumbar Disc Herniation By Percutaneous Endoscopic Lumbar Discectomy

ObjectiveA retrospective study to analyze the effect of Modic changes on the treatment of lumbar disc herniation(LDH)by Percutaneous Endoscopic Lumbar Discectomy(PELD).Methods152 patients suffered from LDH with or without Modic changes treated in our hospital from January 2017 to December 2018 were included in the study.All patients underwent PELD treatment.According to the lumbar spinal Magnetic Resonance Imaging(MRI),the patients were divided into Modic changes group(group A)and non Modic changes group(group B).According to the signal changes of the endplate on MRI,it can be divided into three types:Modic Ⅰ,ModicⅡ and Modic Ⅲ;According to the height of vertebral body accumulated by the abnormal changes of the endplate in the midsagittal position of MRI,Modic changes were divided into three degrees,mild,moderate and severe.The patients were followed up by telephone and outpatient consultation for one year.Visual Analog Scale(VAS)pain scores and modified Macnab criterion were recorded before surgery,1 day after surgery,1,3,6,12 months after surgery,and statistical analysis was conducted.Results137 patients got the final follow-up.There were 70 patients in group A,and 67 in group B.There were 30 type Ⅰ Modic changes,40 type Ⅱ Modic changes;There were 39 cases of mild Modic changes,27 cases of moderate Modic changes,and 4 cases of severe Modic changes.There were no significant differences in the number of cases,gender,average age,mean body mass index and pathological segment between the two groups(P>0.05).Postoperative VAS scores at one day,1,3,6 and 12 months of low back pain and leg pain in the two groups were significantly lower than the preoperative one,the differences were statistically significant(P<0.05).Postoperative VAS scores of low back pain were higher in group A than in group B at 1,3,6 and 12 months(P<0.05).At 3,6 and 12 months after surgery,The modified Macnab criterion in group B were higher than that in group A with statistically significant differences(P<0.05).The Postoperative VAS scores at one day,1,3,6 and 12 months of low back pain and leg pain between type Ⅰ Modic changes and ⅡModic changes were no statistically significant differences(P>0.05).There were no significant differences in the modified Macnab criterion between typeⅠ and type Ⅱ Modic changes 1,3,6,12 months after operation(P>0.05).There were no statistically significant differences on VAS scores of low back pain before and 1 day after surgery and 1,3,6 and 12 months after surgery among different degrees of Modic changes(P>0.05).The differences on leg pain VAS scores of at 1,3,and 6 months after surgery were statistically significant between mild Modic changes and severe Modic changes,so were between moderate Modic changes and severe Modic changes(P<0.05).1,3,6,12 months after the surgery,there were no statistically significant differences among the modified Macnab criterion in Modic changes of different degrees(P>0.05).There were 10 cases(7.3%)recurred during the follow-up of the two groups,7 cases recurred in Modic group,3 cases in non Modic group,and there was no significant correlation between Modic changes and the recurrence after PELD(χ2=1.543,P>0.05).ConclusionPELD is a safe and effective technique on the treatment of LDH with Modic changes,but Modic changes can affect the relief of postoperative low back pain.There is no significant difference in postoperative pain intensity between different types or varying degrees of Modic changes,but severe Modic changes may affect the relief of postoperative leg pain.Modic changes is not a risk factor for postoperative recurrence of lumbar disc herniation treated by PELD.