Evaluation The Lumbar Dorsal Muscle By MRI And Its Correlation With Quality Of Life In Middle-aged And Elderly People

Background and objectives:Lumbar dorsal muscle plays an important role in the dynamic balance and functional movement of the spine.Lumbar dorsal muscle degeneration is closely related to lumbar degenerative disease(LDD).Accurate evaluation of lumbar dorsal muscle is very important for understanding the pathogenesis,evaluation and treatment decision of LDD.At present,the commonly used muscle evaluation methods include tissue biopsy,electromyography,muscle strength endurance measurement and imaging evaluation,but there is still a lack of evaluation methods and unified standards that can accurately reflect the quality of life of the middle-aged and elderly people.Magnetic resonance imaging(MRI)has the advantages of non-radioactivity and high contrast resolution of soft tissue,so it has become a common method to qualitatively evaluate the changes of muscle morphology and the degree of steatosis.Searching for the detection sequence and evaluation parameters of lumbar dorsal muscle MRI reflecting the health-related quality of life of middle-aged and elderly people has become the focus of research.Accurate evaluation of lumbar dorsal muscle degeneration can provide new ideas and theoretical basis for the pathological mechanism,evaluation criteria,treatment and rehabilitation of LDD.The purpose of this study was to explore the MRI method to evaluate the degree of lumbar dorsal muscle degeneration in middle-aged and elderly people.Optimization of detection sequences and methods based on their correlation with health-related quality of life.Providing a scientific basis for further improving the MRI evaluation technology of the degree of lumbar dorsal muscle degeneration in the middle-aged and elderly population.Methods:This study is a cross-sectional clinical study,which has passed the ethical approval of clinical research in Southwest Hospital and the examination and approval of China Clinical trial Registration Center.The health-related quality of life(HRQOL)of all subjects was assessed by Roland-Morris questionnaire(RMQ)and 36-Item Short Form Health Survey(SF-36).The cross-sectional area(CSA),functional cross-sectional area(FCSA),relative cross-sectional area(RCSA),relative functional cross-sectional area(RFCSA)and fat infiltration ratio(FIR)of lumbar dorsal muscles in L1～S1 segment were measured and calculated by Image J software combined with 3.0T lumbar MRI T2 WI images.The correlation between MRI parameters of lumbar dorsal muscle and HRQOL was analyzed by Pearson or Spearman,the efficiency of each parameter was evaluated by receiver operating characteristic(ROC)curve,and the influence of MRI evaluation parameters of lumbar dorsal muscle on HRQOL was analyzed by Logistic regression.35 subjects with L1～S1 segmental multifidus FIR were evaluated by 3.0T lumbar MRI T2 WI sequence combined with Image J software and chemical shift-encoding water-fat imaging(Dixon)sequence,respectively.MRI T2 WI sequence combined with Image J software and single-voxel MR spectroscopy(SMRS)were used to evaluate the FIR of multifidus of L4/5 segment in 67 subjects.Finally,the correlation between FIR of multifidus and HRQOL was evaluated by Pearson or Spearman correlation analysis.Results:111 subjects were included according to the inclusion and exclusion criteria,including 20 males and 91 females,with an average age of 61.95 ±8.44 years.All the subjects completed the T2 WI sequence detection of L1～S1 segment,of which 67 subjects completed the SMRS sequence detection of L4/5 segment and 35 subjects completed the Dixon sequence detection of L1～S1 segment.The results of lumbar MRIT2 WI sequence images combined with Image J software analysis suggest that:A significant positive correlation was found between RCSA and RFCSA of lumbar dorsal muscle and SF36 scores in L1～S1 Segments(both P <0.05),with the largest correlation between RFCSA in L4/5 segment and SF-36(r=0.582,P <0.01),the smallest correlation between FCSA in L2/3 segment and SF-36(r=0.213,P<0.05).The FIR of lumbar dorsal muscle was significantly negatively related between L1～S1 segment and SF-36 scores(all P <0.01),with the largest absolute correlation coefficient for L1/2 FIR(r=-0.498,P<0.01).FCSA,RCSA and RFCSA of lumbar dorsal muscle in L1～S1 segments were significantly negatively associated with RMQ scores(both P <0.05),with the largest significant correlation between RFCSA in L4/5 segment and RMQ(r =-0.639,P <0.01),the smallest significant correlation value between FCSA in L2/3 segment and RMQ(r=-0.200,P<0.05).The FIR of lumbar dorsal muscle was significantly positive related between L1～S1 segment and RMQ scores(all P <0.01),with the largest correlation coefficient for L1/2 FIR(r=0.551,P<0.01).Among the parameters reflecting the size of the lumbar dorsal muscle,the L4/5 segment RFCSA evaluated the SF-36 and RMQ with the largest AUC respectively(0.807,0.876,all P<0.05).Among the parameters reflecting the fat infiltration in the lumbar dorsal muscle,the L1/2 segment FIR evaluated the SF-36 and RMQ with the largest AUC,respectively(0.770,0.818,all P <0.05).Multivariate Logistic regression analysis was conducted with age,sex,BMI,L4/5RFCSA and L1/2FIR as independent variables and SF-36 or RMQ as dependent variables.The results showed that the association of RFCSA with SF-36 and RMQ in the L4/5 segments remained statistically significant after adjust for age,gender and BMI(P <0.05).Comparison of T2 WI sequence and SMRS sequence to evaluate the correlation between FIR and health-related quality of life score(SF-36 and RMQ)of L4/5 segmental multifidus.The FIR evaluated by T2 WI sequence was moderate negatively correlated with SF-36(r=-0.443,P<0.05)and moderate positively correlated with RMQ(r=-0.433,P<0.05).The FIR evaluated by SMRS sequence was weakly negatively correlated with SF-36(r=-0.247,P<0.05)and weakly positively correlated with RMQ(r=-0.271,P<0.05).Comparison of T2 WI sequence and Dixon sequence to evaluate the correlation between FIR and health-related quality of life score(SF-36 and RMQ)of L1～S1 segmental multifidus.The results showed that there was a moderate negative correlation between FIR and SF-36 in each segment of L1～L4 in Dixon sequence group(r is respectively-0.496,-0.410,-0.429,all P<0.05).There was a weakly negative correlation between FIR and SF-36 in each segment of L1～L4 in T2 WI sequence group(r is respectively-0.342,-0.362,-0.385,all P<0.05).There was a weak negative correlation between the two sequences in L4/5 segment,but there was no significant correlation in L5/S1segment(P>0.05).The correlation between FIR of multifidus in L1/2 segment and RMQ was moderately positive in Dixon sequence(r=0.419,P<0.05)and weakly positive in T2 WI sequence(r=0.386,P<0.05).There was no significant correlation between FIR of multifidus and RMQ in other segments(P>0.05).Conclusions:1.The degree of lumbar dorsal muscle degeneration assessed by MRI is closely related to the health-related quality of life of the middle-aged and elderly people.Compare to cross-sectional area,functional cross-sectional area,relative cross-sectional area,fat infiltration rate,the relative functional cross-sectional area is the best correlation parameter.2.Compared with the MRI results of different segments of lumbar vertebrae,the relative functional cross-sectional area of lumbar dorsal muscle in L4/5 segment had the strongest correlation with health-related quality of life.3.The degree of lumbar dorsal muscle degeneration evaluated by three kinds of MRI sequence has a certain correlation with the health-related quality of life of the middle-aged and elderly people.Compared with T2 WI sequence and SMRS sequence,the detection result of Dixon sequence has the strongest correlation.