Imaging Characteristics of Chronic Lumbar Disc Herniation From the Perspective of Core Muscles and Subcutaneous Fat Tissue Thickness
Condition: Lumbar Disc Herniation
MeSH terms: Intervertebral Disc Displacement; Hernia
Study type: Observational

Summary: 
      Fat infiltration and atrophy of lumbar muscles are related to spinal degenerative conditions,
      which can be seen reliably on MRI scans of lumbar disc herniation (LDH) patients. The aim of
      this study was to investigate the relationship between the degeneration of core muscles,
      obesity and chronic LDH. Fifty-five healthy volunteers and fifty-five chronic LDH patients
      (the course of the disease is more than six months) were enrolled. Core muscle percent fat
      and subcutaneous fat tissue thickness(SFTT) were used as the outcome measure, and logistic
      regression and independent samples t-test as the analytical methods to compare the
      relationship of the following five independent variables (erector spinae, rectus abdominis,
      [transversus abdominal, internal abdominal oblique, and external abdominal oblique muscle],
      lumbar multifidus, and psoas major muscles) and SFTT with LDH.
    


Intervention name(s): Magnetic Resonance Hydrolipid Separation Imaging
Intervention type(s): Diagnostic Test
Intervention description(s): MRHS was used to measure different muscle percent fat of core muscles. MRHS, also called Dixon imaging, mainly used the different resonant frequency between the hydrogen nuclei in water and in fat to perform the data acquisition at different echo times (TE). The Dixon sequence basically acquires two images, one image with water and fat signals in-phase and the other with water and fat signals out-of-phase: the sum and subtraction of the two images allow the production of a water-only image and a fat-only image. Scanning equipment: 3.0T superconducting Siemens Skyra Scanner.
Scanning parameters: TR5.36ms, TE1.24ms, Flip Angle 9°, number of layers was 44-60, thickness of layer was 5.0 mm, layer interval 1.0mm, FOV50cm×50cm, the scanning time was 12s×5.
Observational model: Case-Control
Time perspective: Retrospective
Sampling method: Probability Sample
Study population: 
        Inclusion Criteria:

        ①patients who meet the diagnostic criteria for LDH based on overall consideration of their
        symptoms, signs, and radiological findings (MRI)； ②patients aged 20 to 55 years, including
        20 and 55 years, male or female; ③Patients with a history of LDH for 6 months and/or above;
        ④patients who have signed the informed consent.

        Exclusion criteria:

        ①patients with LDH causing radiculopathy or cauda equina syndrome; ②patients with other
        diseases such as spinal stenosis, ankylosing spondylitis that causes low back pain;
        ③patients with a previous history of spinal surgery, traumatic injury to the spine;
        ④patients with bone tuberculosis, osteoporosis and bone tumors; ⑤patients with other severe
        cardiovascular and cerebrovascular diseases, digestive and hematopoietic system diseases;
        patients with diabetes mellitus Autoimmune diseases or other metabolic diseases; patients
        with mental diseases;