Do variations in paraspinal muscle morphology and composition predict low back pain in men?

Area of Science:

• Musculoskeletal health
• Biomedical imaging
• Epidemiology

Background:

• Low back pain (LBP) is a common condition with multifactorial causes.
• The role of paraspinal muscle morphology in LBP development and persistence remains debated.
• Previous studies have yielded inconsistent findings regarding muscle size, composition, and asymmetry as LBP predictors.

Purpose of the Study:

• To investigate whether paraspinal muscle morphology variations predict the onset and progression of LBP.
• To examine the association between muscle characteristics and LBP frequency, intensity, and sciatica over 15 years.
• To clarify the long-term predictive value of muscle morphology in a population-based sample.

Main Methods:

• A population-based longitudinal study of 99 Finnish men.
• Baseline assessment included structured interviews, physical examination, and magnetic resonance imaging (MRI) of paraspinal muscles (multifidus and erector spinae) at L3-L4 and L5-S1.
• Follow-up interviews were conducted at 1 and 15 years to assess LBP status.

Main Results:

• Few paraspinal muscle parameters predicted changes in LBP frequency, intensity, or sciatica over 1 and 15 years.
• Findings were inconsistent across different muscles and spinal levels.
• Greater fatty infiltration in multifidus and erector spinae muscles at L5-S1 was linked to a higher risk of persistent LBP at 1-year follow-up.
• Associations were not confounded by body mass index or physical activity levels.

Conclusions:

• Paraspinal muscle morphology variations identified via MRI have a limited role in predicting short- and long-term LBP in men.
• Fatty infiltration at L5-S1 may be a specific indicator for persistent LBP risk.
• Further research is needed to fully understand the complex relationship between muscle structure and LBP.