ATTENTION OF POSTURAL CONTROL ON FOOT SOMATOSENSOR DISTURBANCE CAUSED BY THE COMPRESSION OF BLOOD VESSELS

Abstract

This study aimed to compare the center of foot pressure (CFP) during different ischemia periods by cuff compression. Ten healthy young adult males held their CFP for 1 min before and after cuff compression (250 mmHg) of lower limb blood vessels during two different compression periods (10 min and 26 min). Two-point discrimination thresholds and electric stimulus perception thresholds of each subject's right foot sole were measured during cuff compression to examine changes in the perceived level of cutaneous and proprioceptive sensation by blood flow inhibition. In addition, oxygenation kinetics in the anterior tibial muscle tissue was examined by near-infrared spectroscopy during cuff compression. The CFP was evaluated by using 36 parameters. CFP deflection tended to increase after cuff compression and to be larger over a long ischemic time (26 min) as compared with a short ischemic time (10 min). The proprioceptive perception threshold using electric stimulation showed a significant interaction and was higher after 26 min ischemia than at the initial timepoint and after 10 min ischemia. The delta[Oxy Hb/Mb], delta[Deoxy Hb/Mb] and Tissue oxygenation index (TOI) changed significantly after both ischemic conditions than at the initial condition. There was no significant difference in the Tissue oxygenation index and delta[Deoxy Hb/Mb] between both ischemic conditions. Many parameters regarding the deflection velocity and anteroposterior and lateral deflection had significantly larger values after 26 min ischemia than at the initial time point and after 10 min ischemia. Postural deflection may not be affected by the oxygen deficiency of muscle tissues caused by the compression of blood vessels for 10 min, but strongly affected by the cutaneous and proprioceptive sensation disturbances occurring from compression lasting over 10 min.