Relationship between paraspinal muscle crosssectional area and relative proprioceptive weighting ratio of older persons with lumbar spondylosis

Purpose: The purpose of this study was to examine the relationship between the paraspinal muscle cross-sectional area and the relative proprioceptive weighting ratio during local vibratory stimulation of older persons with lumbar spondylosis in an upright position. Subjects: In all, 74 older persons hospitalized for lumbar spondylosis were included. Methods: We measured the relative proprioceptive weighting ratio of postural sway using a Wii board while vibratory stimulations of 30, 60, or 240 Hz were applied to the subjects’ paraspinal or gastrocnemius muscles. Back strength, abdominal muscle strength, and erector spinae muscle (L1/L2, L4/L5) and lumbar multifidus (L1/L2, L4/L5) cross-sectional areas were evaluated. Results: The erector spinae muscle (L1/ L2) cross-sectional area was associated with the relative proprioceptive weighting ratio during 60Hz stimulation. Conclusion: These findings show that the relative proprioceptive weighting ratio compared to the erector spinae muscle (L1/L2) cross-sectional area under 60Hz proprioceptive stimulation might be a good indicator of trunk proprioceptive sensitivity.