Abstract
It is difficult for cerebrovascular disease patients to maintain the standing position while holding the shoulder in the flexed position and flexing the shoulder. It is thought that center-of-gravity line deviates from the base of support because holding the shoulder in the flexed position or flexing the shoulder influence the body alignment and generate addtional forces. The center of plantar pressure moves toward the center of gravity line to avoid leaving the base of support. Therefore, clarifying the movement pattern of the center of plantar pressure while holding the shoulder in the flexed position and flexing the shoulder is important when we perform a physical therapy evaluation for patients with instability in standing. In this study, trace of the center of plantar pressure movement during holding the shoulder in the flexed position and flexing the shoulder in standing was investigated to evaluate postural control in healthy subjects. We analyzed the trace of the center of plantar pressure in standing as follows: 1) The center of plantar pressure average displacement with change of the shoulder flexion angle (0°, 30°, 60°, 90°, 120°, 150° and 180°); 2) The trace pattern of the center of plantar pressure in flexing the shoulder. We found trace patterns of center of plantar pressure which are common to subjects holding the shoulder flexed at 30°, 60° and 90°. Also, in the pattern classification of trace patterns of the center of plantar pressure during flexing the shoulder, we identified 5 patterns as follows: front S pattern, front reverse S pattern, rear S pattern, front C pattern and front reverse C pattern. We think that a force was generated by holding the shoulder in the flexed position and that flexing the shoulder was related to some of the patterns produced. It is important that the trace pattern of center of plantar pressure is ealuated while holding the shoulder in the flexed position and flexing the shoulder.
