Figure 1

Representative MRI and US images of the LMF ACSA at lumbar vertebral bodies L3-L5. (A) Sagittal MRI image with identified lumbar vertebral bodies L3-L5; (B) Transversal MRI images of LMF ACSA at L3, L4 and L5; (C) Transversal panoramic US images of LMF ACSA at L3, L4 and L5. MRI magnetic resonance imaging, US ultrasound, LMF ACSA lumbar multifidus anatomical cross-sectional area.