Dynamic analysis of trunk flexion after stroke

Abstract

Objective: To quantify trunk movement and lower-extremity weight bearing in patients with stroke-associated hemiparesis compared with healthy subjects.

Design: Controlled study with 2 groups: persons with hemiparesis and healthy controls.

Setting: Geriatric center offering rehabilitation services.

Participants: A convenience sample of 15 persons with poststroke hemiparesis (age, 69.4+/-12.0y; > or =3mo poststroke; total motor function range, 63-95/100) on the Fugl-Meyer Assessment and of 13 healthy persons (age, 67.8+/-7.5y).

Interventions: Subjects were seated on a chair placed on a forceplate with their feet on 2 additional forceplates. A target was placed directly in front of or at a 45 degrees angle from the midline at 66% of the nonparetic/dominant arm length. Subjects' task was to touch the target with their forehead. Main outcome measures Amplitude and speed of trunk movements, displacement of the global center of pressure (COP), and percentage of body weight distributed on the buttocks and the feet.

Results: Despite speed and amplitude comparable to that of the healthy subjects (NS), subjects with hemiparesis (HS) had less COP displacement (HS, 33.7+/-6.9; NS, 40.5+/-9.2), resulting in a lower weight-bearing value on the feet (HS for the paretic foot, 2.3%+/-3.6%; HS for the nonparetic foot, 2.2%+/-2.9%; NS for the nondominant foot, 5.4%+/-3.4%; NS for the dominant foot, 5.2%+/-4.0%).

Conclusions: The similar amplitude of trunk flexion with a decreased displacement of COP and a lower weight bearing on the feet suggest smaller anterior displacement of the body mass. It is possible that trunk movements in persons with hemiparesis are executed by the upper trunk with very little anterior tilt of the pelvis.