Effect of neck muscles and gluteus medius vibrations on standing balance in healthy subjects
Dr Stéphanie CHALLOIS LEPLAIDEURa, Mr Karim JAMALa, Mrs Emilie LEBLONGa, Mrs Lucie CHOCHINAa, Prof Isabelle BONANa
a CHU RENNES
Introduction: Muscle vibration can be used to improve the center of pressure (CoP) shift . Several muscle sites have been used for various diseases without that we know their respective interest.
Objective: To compare the effects and post-effects of neck muscle vibrations (NMV) and gluteus medius vibrations (GMV) on balance in healthy subjects
Methods: Thirteen healthy subjects, mean 23 years, right handed were tested on posturography, closed eyes, in standing position. They received successively left NMV and right GMV in a randomized order. The variation of the deviation of CoP on the médiolatéral plane was evaluated under vibration stimulation (5min) , at the end of the vibration and 5 minutes after .
Results: GMV induce a CoP movement to left side (9 responders) (mean 5.21 mm; SD 4.79; p = 0.003). At the end of the vibration, the effect remained sgnificant (mean 4.73, SD 4.02; p = 0.001) and after 5 minutes, the subjects restored their initial balance (mean 1.25, SD 6.82; p = 0.33). For NMV, a movement toward leftside was observed only in 5 subjects but this deviation seemed to be maintained at 5min. The CoP deviation was not significant during (p = 1), immediately after ( p = 0.72), and after 5 minutes of NMV (p = 0.89).
Discussion: GMV cause a lateral shift in 70% of the subjects of nearly 5 mm. The effect of NMV was lower and less constant (only 5 responders) but sustainable. This could be explained by a sensorimotor peripheral action for GMV while NMV would involve high level body representation in space.
Keywords : balance, posture , vibration