Comparative Study Of Elastic Ultrasound Of Thoracolumbar Fascia Between Patients With Chronic Low Back Pain And Normal People

BackgroundChronic low back pain(CLBP),also known as chronic non-specific low back pain,a syndrome where the main symptoms are pain and discomfort in the lower back,lumbosacral and buttocks.CLBP is a very common musculoskeletal system disease.Most chronic low back pain cannot be accurately diagnosed with tissue structural lesions,and the specific pathological mechanism is not clear.However,chronic low back pain not only causes the physical pain of patients.As time goes by,the patients have fear and anxiety about pain and naturally avoid activities that cause pain.The quality of life of the patients are reduced.Eventually the inability to work leads to disability and a huge waste of social medical resources.Studies have reported that the imbalance of the functional state of muscle tissue is an importantfactor leading to low back pain.The thoracolumbar fascia(TLF)is located in the thoracic and lumbar segments of the spine.It is the deep fascia of the back and is formed by a complex arrangement of multiple layers of fascia and aponeurosis.The posterior layer of thoracolumbar fascia(PLF)is mainly composed of the aponeurosis of the latissimus dorsi and serratus posterior inferior muscle,which plays an important role in the stability of the spine and pelvis.The role of TLF in LBP has attracted more and more attention.Foreign studies have found that patients with chronic or recurrent CLBP have thickened lumbar connective tissue and reduced TLF shear strain measured by ultrasound,suggesting that TLF may be involved in the pathophysiology of CLBP.However,there are no experimental studies on the assessment of TLF changes in CLBP patients in China.ObjectivesIn this study,Strain elastography(SE)was used to observe the difference in TLF thickness and elasticity index(EI)between healthy people and CLBP patients.And the aim of our study was to analyze the changes of TLF thickness and El in CLBP patients.At the same time combined with body mass index(Body mass index,BMI)and observation indicators of CLBP patients such as Oswestry disability index(ODI)questionnaire,Roland-Morris disability questionnaire(RMDQ),simple McGill pain questionnaire,lumbar JOA score form.We analyzed the correlation between the thickness of TLF and the changes of EI in CLBP patients with various observation indicators,to provide new ideas for the diagnosis and treatment of CLBP.MethodsOur study enrolled 22 CLBP patients(10 males and 12 females)who met the inclusion criteria and came to the Pain Department of Jinan Central Hospital from July 2020 to December 2020.According to the age of the patients,the CLBP patients were divided into two groups:young group and middle-aged group.Young group:10 people aged 30-45 years old.Middle-aged group:age 46-60 years old,a total of 12 people.22 healthy controls(9 males and 13 females)matching the gender,age,education level and BMI of the CLBP group were selected as the healthy group.The subjects in the healthy group were divided into two groups according to their age:the young group and the middle-aged group.Young group:10 people aged 30-45 years old.Middle-aged group:aged 46-60 years old,a total of 12 people.We recorded the subjects gender,age,years of low back pain(years),height,weight,physical examination,concomitant diseases and other basic information.We assessed the patient scores on each scale.The SE technology was used to measure the thickness and EI of the posterior layer of the thoracolumbar fascia(PLF)in bilateral L4/5 facet joint(FJ),L5/S1FJ,and between the two facet joints in the healthy group and CLBP patients.SPSS26.0 software was used for statistical analysis of the measurement data.Measurement datas were calculated as mean±standard deviation.Independent sample t-tests were used to compare the fascia thickness and E between the CLBP group and the healthy group.The Paired-samples t-test was used to analyze the difference in the E and thickness of the bilateral fascia of the waist between the two groups.Pearson correlation analysis was used to check the correlation between the data in the CLBP group.P<0.05 indicates a significant difference,P<0.01 indicates a very significant difference.Results1.Results of healthy group:There was no statistical difference in PLF thickness and EI between the left and right sides of healthy subjects(P>0.05);there was no significant difference in PLF thickness between different genders(P>0.05);The difference in the EI of PLF at the right L4/5FJ of different genders was statistically significant(P<0.05),and the EI of women was significantly higher than that of men.There was no statistically significant difference in the EI of PLF at the left and right L4/5FJ-L5S/1FJ,L5/S1FJ of different genders(P>0.05);The difference in PLF thickness between different age groups was not statistically significant(P>0.05);The difference in the EI of PLF at the right L4/5 facet joint between the two groups was statistically significant(P<0.05),and the EI of the middle-aged group was significantly greater than that of the young group.There was no statistically significant difference in the EI of PLF between different age groups in other parts(P>0.05);BMI was positively correlated with the PLF thickness of L4/5FJ-L5/S1FJ(r=-0.457,P<0.05)and the PLF thickness of L5/S1FJ(r=-0.572,P<0.01).2.Results of the CLBP group:There was no statistically significant difference in the thickness and EI of the bilateral PLF(P>0.05);There was no statistically significant difference in PLF thickness and EI between male and female(P>0.05);The difference in PLF thickness and EI between the young group and the middle-aged group was not statistically significant(P>0.05);In the PLF data on the left,there was a correlation between the RMDQ score and the EI of PLF at L4/5FJ and the EI of PLF at L5/S1FJ.There was a correlation between PRI and the EI of PLF at L5/S1FJ.The RMDQ score was negatively correlated with the EI of PLF at L4/5FJ(r=-0.494,P<0.05)and L5/S1FJ(r=-0.610,P<0.01).Pain Rating Index(PRI)was negatively correlated with the EI of PLF at L5/S1FJ(r=-0.510,P<0.05);In the PLF data on the right,there was a correlation between the RMDQ score and the EI of the PLF at L4/5FJ and the EI of the PLF between L4/5FJ-L5/S1FJ.There was correlation between the PRI evaluation and the EI of PLF at L5/S1FJ and the EI of PLF between L4/5FJ-L5/S1FJ.The level of RMDQ score and the EI of PLF at L4/5FJ(r=-0.545,P<0.01)and between L4/5FJ-L5/S1FJ(r=-0458,P<0.05)were negative related.The PRI evaluation was negatively correlated with the EI of PLF at L5/S1FJ(r=-0.500,P<0.05)and the EI of PLF between L4/5FJ-L5/S1FJ(r=-0.428,P<0.05).3.Comparison between the healthy group and the CLBP group:There was no statistical difference between the two groups in gender,age,height,weight,and BMI(P>0.05);There was a significant difference in PLF thickness between CLBP group and healthy group(P<0.05),CLBP group was significantly higher than healthy group;The E of PLF between the CLBP group and the healthy group was significantly different(P<0.05),and the EI of PLF in the CLBP group was significantly lower than that of the healthy group.Conclusion1.Strain elastography can be used as a non-invasive,non-radiation,real-time imaging technology for TLF inspection.2.The average PLF thickness of male is higher than that of female;The EI of PLF at L4/5FJ on the right side of female is significantly higher than that of male;BMI is positively correlated with PLF thickness.CLBP patients have thicker PLF thickness than healthy people,and EI is larger than healthy people,while RMDQ and PRI are negatively correlated with PLF EI.The study confirmed the results of PLF positive changes in CLBP.