TURNING DYSFUNCTION AFTER STROKE AND ITS ASSOCIATION TO TRUNK CONTROL

Y.-C. Teng¹, P.-J. Liang¹, S.-C. Lee²

Background: Turning is a challenging task and has been reported as one of the activities that most frequently leads to falling after stroke. Patients with stroke need more time and a greater number of steps to complete turns than age-matched healthy control groups indicating turning dysfunction. Recent studies showed that turn duration and steps were highly correlated with trunk control using the Functional Assessment for Control of Trunk (FACT). However, the underlying mechanism has still been under investigation. The correlation of trunk range of motion (ROM), trunk muscle strength and turning performance remains unknown.

Purpose: The aim of the study was to investigate the correlation between turning performance and trunk control.

Methods: Stroke patients were recruited from an out-patient clinic, department of physiotherapy, regional hospital. The inclusion criteria were survivors of a single and unilateral stroke with hemiparesis experienced at least 6 months prior to their participation in the study, and able to walk independently over 10 meters without walking aids or orthoses. All participants were evaluated for turning performance and trunk control. They were instructed to turn on the spot 360 degrees toward both sides. Duration and center of mass (COM) angular velocity during turns were measured by three inertial sensors which were fixed on upper shoes and lower trunk. Trunk ROM including trunk flexion, extension, side bending and rotation were measured by the tape while the trunk muscle strength including trunk flexors, extensors, side flexors and rotators by the MicroFET 3 dynamometer. The Trunk Impairment Scale (TIS) was used to assess the motor impairment of the trunk after a stroke including static sitting balance, dynamic sitting balance and coordination subscales.

Results: A total of 28 patients with stroke were recruited in this study (age 59±9 years, 29% female, post-stroke duration 66±56 months, 57% left affected side, 43% ischemic stroke). Duration and COM angular velocity during turns toward affected side were significantly longer (4.72±2.04 vs 3.57±1.96 s, p=0.037) and slower (121.28±33.76 vs 138.49±39.75 degree/s, p=0.009) than toward sound side. Turn duration toward affected side was significantly correlated with trunk flexors strength (r=0.382, p=0.019), side flexors strength (r=0.397, p=0.041), dynamic sitting balance (r=0.393, p=0.043) and coordination of trunk movement (r=0.498, p=0.008). The COM angular velocity during turns toward affected side was significantly associated with trunk flexion (r=0.550, p=0.003) and rotation ROM (r=0.409, p=0.034). Turn duration toward sound side only significantly correlated with trunk rotators strength (r=0.390, p=0.044).    

Conclusion(s): Stroke patients had the greater difficulties in turning toward affected side by showing the longer duration and reduced COM displacement. The trunk ROM, muscle strength and control could affect turning performance, especially toward affected side. This could explain the most falls occurring when they turned toward the affected side.

Implications: These findings are expected to contribute to the development of effective strategies for enhancing turning ability through improvement of trunk ROM, trunk strength and trunk control for clinical physiotherapy practice.

Funding, acknowledgements: The study was supported by a grant from the Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation (TCRD-TPE-109-09).

Keywords: Stroke, Trunk, Turns

Topic: Neurology: stroke

Did this work require ethics approval? Yes

Institution: Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation

Committee: Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation

Ethics number: 08-XD-051