Objective:To explore the difference and clinical significance of paraspinal muscle degeneration between single-segment degenerative lumbar spondylolisthesis and degenerative lumbar spinal stenosis.Methods:From January 2014 to October 2020, a retrospective analysis of 30 patientswere diagnosed with L 4,5 degenerative lumbar spondylolisthesis, aged 61.63±8.42 years old (range 44 to 82 years old), body mass index 24.07±3.17 kg/m 2 and 30 patientswere diagnosed with L 4,5 degenerative lumbar spinal stenosis, aged 59.67±12.89 years old (range 31 to 80 years old), body mass index 25.29±3.48kg/m 2, both of them went on surgery in department of spine surgery, shengjing hospital, China Medical University.30 healthy people were selected from outpatient physical examination in the control group, aged 58.33±7.36 years old (range 52 to 83 years old), body mass index 25.72±2.58 kg/m 2. These three groups were all male. Select all patients with L 3,4, L 4,5 and L 5S 1 disc level axial MRI images, and use the deep learning automatic segmentation measurement system developed by our hospital and Shenyang Institute of Automation Chinese Academy of Sciences to measure multifidus muscle cross sectional area (MMCSA), erector spinae cross sectional area (ESCSA), multifidus muscle fatty infiltration rate (MMFIR) and erector spinae fatty infiltration rate (ESFIR). One-way ANOVA was used to test the imaging parameters of multifidus and erector spinae of the three groups, and LSD- t test was used to compare the imaging parameters in each segment of paraspinal muscles. Results:The gender of three groups were male, there was no significant difference in age ( H=5.303, P>0.05), and there was no significant difference in body mass index ( F=2.267, P>0.05). Multifidus muscle cross-sectional area in L 3,4: degenerative lumbar spondylolisthesis groupincreased 189.11 mm 2 compared with degenerative lumbar spinal stenosis group ( P=0.010). Multifidus muscle cross-sectional area in L 4,5: compared with healthy people group, degenerative lumbar spondylolisthesis group decreased 205.52 mm 2 ( P=0.002), while degenerative lumbar spinal stenosis group decreased 184.14 mm 2 ( P=0.006). Multifidus muscle cross-sectional area in L 5S 1: compared with degenerative lumbar spinal stenosis group, degenerative lumbar spondylolisthesis group decreased 174.93 mm 2 ( P=0.018); compared with healthy people group, degenerative lumbar spondylolisthesis group decreased 406.06 mm 2 ( P<0.001), while degenerative lumbar spinal stenosis group decreased 231.13 mm 2 ( P=0.002). Erector spinae cross sectional area in L 4,5: compared with healthy people group, degenerative lumbar spinal stenosis group decreased 398.70 mm 2 ( P=0.006). Erector spinae cross sectional area in L 5S 1: compared with degenerative lumbar spinal stenosis group, degenerative lumbar spondylolisthesis group decreased 500.02 mm 2 ( P<0.001); compared with healthy people group, degenerative lumbar spinal stenosis group decreased 455.37 mm 2 ( P<0.001). Compared with healthy group, the multifidus muscle fatty infiltration rate of degenerative lumbar spondylolisthesis group in L 3,4 increased 4.96% ( P=0.001). Compared with degenerative lumbar spinal stenosis group, the erector spinae fatty infiltration rate of degenerative lumbar spondylolisthesis group in L 5S 1 decreased 5.41% ( P=0.004). Compared with healthy group, the erector spinae fatty infiltration rate of degenerative lumbarspinal stenosis group in L 5S 1 increased 5.02% ( P=0.008) . Conclusion:Paraspinal muscle cross sectional area of each segment in degenerative lumbar spondylolisthesis group and degenerative lumbar spinal stenosis group decreased in different degrees. In degenerative lumbar spondylolisthesis group, the degree of multifidus muscle fat infiltration was more significant, while indegenerative lumbar spinal stenosis group,the degree of erector spinal fat infiltration was higher.

Objective:To analyze the incidence and epidemiological characteristics of traumatic spinal cord injury in China in 2018.Methods:Multi-stage stratified cluster sampling was used to randomly select hospitals capable of treating patients with spinal cord injury from 3 regions，9 provinces and 27 cities in China to retrospectively investigate eligible patients with traumatic spinal cord injury admitted in 2018. National and regional incidence rates were calculated. The data of cause of injury，injury level，severity of injury，segment and type of fracture，complications，death and other data were collected by medical record questionnaire，and analyzed according to geographical region，age and gender.Results:Medical records of 4，134 patients were included in this study，with a male-to-female ratio of 2.99∶1. The incidence of traumatic spinal cord injury in China in 2018 was 50.484 / 1 million （95% CI 50.122-50.846）. The highest incidence in the Eastern region was 53.791 / 1 million （95% CI 53.217-54.365）. In the whole country，the main causes of injury were high falls （29.58%），as well as in the Western region （40.68%），while the main causes of injury in the Eastern and Central regions were traffic injuries （31.22%，30.10%）. The main injury level was cervical spinal cord in the whole country （64.49%），and the proportion of cervical spinal cord injury in the Central region was the highest （74.68%），and the proportion of lumbosacral spinal cord injury in the Western region was the highest （32.30%）. The highest proportion of degree of injury was incomplete quadriplegia （55.20%），and the distribution pattern was the same in each region. A total of 65.87% of the patients were complicated with fracture or dislocation，77.95% in the Western region and only 54.77% in the Central region. In the whole country，the head was the main combined injury （37.87%），as well as in the Eastern and Central regions，while the proportion of chest combined injury in the Western region was the highest （38.57%）. A total of 32.90% of the patients were complicated with respiratory complications. There were 23 patients （0.56%） died in hospital，of which 17（73.91%） died of respiratory dysfunction. Conclusions:The Eastern region of China has a high incidence of traumatic spinal cord injury. Other epidemiological features include high fall as the main cause of injury cervical spinal cord injury as the main injury level，incomplete quadriplegia as the main degree of injury，head as the main combined injury，and respiratory complications as the main complication.