Altered trunk position sense and its relation to balance functions in people post-stroke

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Biomechanics

Background:

• Trunk stability is crucial for balance and functional activities, relying on muscle strength, neural control, and proprioception.
• While trunk muscle strength deficits are known post-stroke, trunk position sense and its role in postural control remain unclear.
• Impaired trunk position sense can lead to instability, impacting overall motor control and function.

Purpose of the Study:

• To investigate whether trunk position sense is impaired in individuals with post-stroke hemiparesis.
• To quantify trunk repositioning errors in stroke survivors compared to healthy controls.

Main Methods:

• Twenty individuals with chronic stroke and 21 non-neurologically impaired controls participated.
• Trunk repositioning error during sitting flexion was measured using an electromagnetic movement analysis system (Flock of Birds).
• Clinical measures of balance (Berg Balance Scale) and postural control (Postural Assessment Scale for Stroke) were also assessed in the stroke group.

Main Results:

• Stroke survivors demonstrated significantly greater trunk repositioning errors in both the sagittal (6.9° vs 3.2°) and transverse (2.1° vs 1.0°) planes compared to controls.
• Significant negative correlations were found between trunk repositioning error and balance/postural control scores (Berg Balance Scale, Postural Assessment Scale for Stroke).

Conclusions:

• Individuals with post-stroke hemiparesis exhibit significant impairments in trunk position sense.
• Trunk position sense deficits correlate with poorer balance and postural control.
• Trunk position sense retraining targeting sagittal and transverse movements warrants investigation as a rehabilitation strategy.