Effect of Postural Metatarsal Bar Orthotic Element on Stability and Leg Muscular Activity. A Randomized Clinical Trial

Posturology allows to treat postural problems by using postural insoles, which will have an effect at the neurophysiological level. Pieces of 1 to 3 millimeters are inserted to stimulate specific receptors located on the sole of the foot, which will affect the muscular proprioception and modify the activation of the ascending muscle chains.

The hypothesis of this work is based on the fact that the use of postural insoles with a 2 millimeters metatarsal bar will influence the displacement of the center of pressure and the muscle activity of the leg when compared with a placebo insoles.

Participants will be healthy subjects and will be divided into two groups, control and experimental. Subjects in the control group will be given a pair of flat insoles (placebo insoles) with 1.2 millimeters polyester resin. Those of the experimental group will be made the same insoles but they will include by thermal fusion a metatarsal bar of 2 millimeters polyester resin in the metatarsal zone corresponding to the 1st, 2nd, 3rd and 4th metatarsal head.

Postural stability analysis will be performed with the force platform of the Biomechanics Institute of Valencia (IBV-Spain) and at the same time an electromyographic analysis in the dominant leg with a surface electromyograph system. Subjects will be assessed with their eyes open and closed under two situations, with footwear and with footwear and insoles.