Trunk biomechanics during walking after sub-acute stroke and its relation to lower limb impairments.

ABSTRACT

BACKGROUND: Trunk function and lower limb strength seem to be the primary predictors for functional independence in acute stroke patients. Gaining a better understanding of their relationship during walking aids in the identification of intrinsic trunk control deficits and underlying lower limb deficits resulting in compensatory trunk movements. METHODS: Fifty-seven subjects with stroke and 57 age- and gender-matched subjects without disability were included. Participants underwent an instrumented gait analysis with a standard total body Plug-In-Gait model, a clinical examination of the lower limbs based on range of motion, strength, muscle tone and several clinical assessment scales such as the Trunk Impairment Scale, Tinetti test and Functional Ambulation Categories. Spatiotemporal parameters and joint angular time profiles were compared between healthy adults and stroke survivors with severe and mild to moderate lower limb impairments. Spm1d was used to compare the joint angular time profiles between groups. FINDINGS: Truncal deviations are present during hemiplegic walking, sub-acute stroke survivors walked with increased thoracic tilt, a neutral frontal position of the pelvis during stance, a pelvic hike during swing, and a more rotated position without crossing of the midline. Patients with more severe lower limb impairments had more pronounced deficits in truncal motion. INTERPRETATION: Setting accurate rehabilitation goals is of major importance during stroke, as well as understanding the underlying mechanisms and causes of the truncal impairments. Although more compensatory trunk deviations were seen in participants with severe lower limb impairments, they should not be considered as the sole contributor of trunk impairments during walking. Results of this study suggest that intrinsic trunk deficits during walking are also present after stroke.