Paraspinal muscles density: a marker for degenerative lumbar spinal stenosis?

Abstract

BackgroundThe condition of paraspinal muscles is known to be associated with some variables such as age, gender, and low back pain. It is generally agreed that these muscles play an important role in the stability and functional movements of the lumbar vertebral column. Although spinal instability has been shown to play an essential role in degenerative lumbar spinal stenosis (DLSS), the role of paraspinal muscles remains elusive. The main purpose of this study was to shed light on the relationship between the condition of paraspinal muscles and symptomatic DLSS.MethodsTwo sample populations were studied. The first included 165 individuals with DLSS (age range: 40–88, sex ratio: 80 M/85 F) and the second 180 individuals without spinal stenosis related symptoms and low back pain (age range: 40–99, sex ratio: 90 M/90 F). Measurements were taken at the middle part of L3 vertebral body, using CT axial images (Philips Brilliance 64). Muscles density was measured in Hounsfield units (HU) using a 50 mm2 circle of the muscle mass at three different locations and the mean density was then calculated. The cross-sectional area (CSA) was also measured using the quantitative CT angiography method. Analysis of Covariance (adjusted for body mass index and age) was performed in order to determine the relationship between the condition of paraspinal muscles and symptomatic DLSS.ResultsIndividuals in the stenosis group had higher muscle density as compared to the control group. The CSA values for the erector spinae (both sexes) and psoas (males) muscles were significantly greater in the stenosis group as compared to their counterparts in the control group. Additionally, density of multifidus (both sexes) and erector spinae (males) muscles was significantly associated with symptomatic DLSS.ConclusionsOur results show that individuals with symptomatic DLSS manifest greater paraspinal muscles density and CSA (erector spinae), compared to the control group. Density of multifidus increases the likelihood of symptomatic DLSS.

Changes in the macroscopic morphology of hip muscles in low back pain

“…Abbas et al. () assessed the psoas major muscle density in patients with degenerative lumbar spinal stenosis and noted that the mean psoas major muscle density was significantly higher in patients compared to controls.…”

“…; Abbas et al. ). Considering the stabilizing function of the psoas major muscle together with the back extensor muscles, hypertrophy of the psoas major muscle might be due to its increased activity, with increased levels of instability associated with degenerative disorders of the lumbar spine (Zhao et al.…”

“…Conditions of muscle such as density, CSA size, and fatty infiltration can be attained via medical imaging modalities providing non‐invasive, direct, reliable, and quantitative information (Abbas et al. ). CT scan and MRI have been employed for measuring CSA and the degeneration rate of muscles in patients with muscular dystrophy (Abbas et al.…”

“…CT scan and MRI have been employed for measuring CSA and the degeneration rate of muscles in patients with muscular dystrophy (Abbas et al. ). The findings obtained from direct and objective examination of muscles will contribute to the explanation of the pathogenesis of LBP, as well as its diagnosis and treatment (Akima et al.…”

Correlations between low back pain and functional capacity among the elderly

“…The static and dynamic stability of the spine is made possible by the joint action of passive tissues and contractile elements 4,5 . Impaired function of the spinal muscles can result in muscle fatigue, due to the excessive overloads that are imposed on the passive elements of the lumbar spine (intervertebral discs, capsules and ligaments) promoting the plastic deformation of these structures, which are sensitive to distension, and triggering low back pain 6 .…”