Nobuyuki KAWATE

Department of Rehabilitation Medicine, Showa University School of Medicine

(Received 27 September 1996; accepted 7 January 1997)

Abstract: The sway paths of the center of gravity in the static-standing posture (CG-static-standing), the static-sitting posture (CG-static-sitting), and the voluntary shifting-sitting posture (CG-shifting-sitting) of hemiparetic stroke patients were analyzed with a gravicorder. Subjects were 51 patients who included 16 women and 35 men, whose mean age was 60.7±9.4 years. A control group of 46 healthy subjects included 27 women and 19 men whose mean age was 58.3±20.6 years. In the sway paths of CG-static-standing, subjects stood on the plate of a gravicorder in Romberg's posture and measurements were taken over 50 sec. For the sway paths of CG-static-sitting, subjects sat on a chair on the plate of a gravicorder and measurements were taken over 50 sec. In these studies, maximal anterior-posterior (AP) distance and right-left (RL) distance of the sway paths of the center of gravity were measured and analyzed. In the sway paths of CG-shifting-sitting, subjects performed voluntary anterior flexion and lateral flexion movements while sitting on the chair; these movements were repeated every 2 sec, and measurements were taken over 40 seconds. In this study, maximal AP distance in anterior flexion and maxmal RL distance in lateral flexion were measured and analyzed. Hemiparetic stroke patients were classified into groups according to standing ability and ambulatory activity: a standing-independent group (N = 40), a standing-impossible group (N = 11); an ambulatory-independent group (N = 31), an ambulatory-impossible group (N = 20). Eleven patients could not be measured in static-standing posture because they could not stand on the plate. However all patients could be measured while static-sitting or shifting-sitting posture. Maxmal RL distance of CG-static-standing and maximal AP, maximal RL distance of CG-static-sitting of the healthy subjects were significantly narrower than that of the patients (p<0.01). Maximal AP distance in anterior flexion and maxmal RL distance in lateral flexion of CG-shifting-sitting of the healthy subjects were wider than that of the patients (p<0.01). The sway paths of CG-static-sitting of patients tended to be narrower, and that of CG-shifting-sitting of patients were significantly wider owing to better standing ability and ambulatory activity. The measurements of the sway paths of the CG are usually made in a standing posture with a gravicorder. Unfortunately, patients who were unable to stand on the plate of a gravicorder could not be measured. We considered that with mesurements of sway paths of the CG in sitting posture, patients who cannot still stand can be measured and examined on the basis of the control of the CG. Objective measurements can be made with a gravicorder, in both stading posture and sitting posture.

Key words: hemiplegia, posture, the sway paths of the center of gravity