Effects of fine plantar stimulation in bilateral pelvic instability: Preliminary study

Introduction This study experiments the incidence of a 2 mm thin median bar (BM®) and truncated median bar (BMt®) plantar relief in bilateral pelvic instabilities, considering the effect of the presence or not of plantar afferences inefficiency on unipedal stabilometric performance [1] . Method Eleven subjects with bilateral pelvic instability at the unipedal pelvic stability test (TSPU) [1] and with a right dominant foot were evaluated. Randomized measurements were performed in bipodal stance on force platform (Medicapteurs©, Fusyo®, France) for 31.6 sec at 40 Hz and then in unipedal stance for 5 sec at 40 Hz on each foot, eyes open and eyes closed under three conditions: – Control; – BM® – BMt®. Repeated and factorial variance analyses were then carried out. The population was divided into two groups according to their Plantar Quotient (PQ) greater or less than 100 determined by the bipodal registrations [2] . Results Seven subjects showed a QP greater than 100 and 4 subjects a QP less than 100. The BM® and BMt® stimuli enhanced the Surface of the Centre of Pressure (CoP) on the right foot with eyes closed. Taking into account the QP, subjects with a QP greater than 100 were enhanced on the surface of the CoP with BMt® only. In this condition, both median bars (BM® and BMt®) enhanced the subjects if their QP was less than 100. Conclusion This study on bilateral pelvic instabilities with thin plantar stimuli confirms their therapeutic interest in these dysfunctions of postural control and illustrates fundamental interest of two notions: – foot dominance and; – efficiency or inefficiency of plantar afferences. These results require further research that considers these intra and inter individual differences.