Contribution of the multifidus muscle for control of upright posture in subjects with spina bifida occulta.

CONTEXT The multifidus muscle plays a role in controlling lumbosacral position and postural sway. One of its attachment sites is the exact site of spina bifida occulta (SBO). OBJECTIVE To investigate the role of the muscle for postural control in SBO. DESIGN Cross-sectional cohort. PARTICIPANTS Eighty subjects with SBO (38 in minor; 42 in major) and controls. INTERVENTIONS N/A. MAIN OUTCOME MEASURES Subjects stood upright on a platform at 0 degrees and on an inclined surface (10 degrees and 20 degrees) with feet in plantarflexion/dorsiflexion, together with eyes open and closed. The platform system measured posture to obtain sway area and sway mean for statistics. RESULTS Upon sway area/mean, the group differences of major/minor SBO vs. control were all significant. Sway means of minor SBO were lower than those of major SBO at corresponding inclined degrees. CONCLUSIONS Subjects with SBO demonstrated increased sway as compared to controls.