Maximal grip force in chronic stroke subjects and its relationship to global upper extremity function

Area of Science:

• Neurorehabilitation
• Clinical Biomechanics
• Stroke Recovery Research

Background:

• Recordable grip strength is a sensitive indicator of upper limb recovery in acute stroke.
• Grip strength is a prognostic factor for long-term recovery after stroke.
• The reliability and utility of grip strength measures in chronic stroke require further investigation.

Purpose of the Study:

• To assess the reliability of maximal voluntary grip force (MVGF) measurements.
• To examine the relationship between paretic grip strength deficit and upper extremity function in chronic stroke patients.

Main Methods:

• Bilateral MVGF was measured three times over three weeks using a strain gauge dynamometer in 15 chronic stroke subjects and 10 controls.
• Paretic MVGF deficit was calculated relative to the nonaffected hand's MVGF.
• Upper extremity function was evaluated using Fugl-Meyer, TEMPA, Box and Block, and finger-to-nose tests.

Main Results:

• MVGF measurements showed high reliability (ICC >0.86) and low standard error in both groups.
• Stroke subjects exhibited significantly impaired paretic MVGF compared to controls (p <0.01).
• Paretic MVGF deficit strongly correlated with performance on all four upper extremity function tests, explaining 62-93% of the variance.

Conclusions:

• Normalized paretic maximal grip strength is a reliable and valuable outcome measure for upper extremity function in chronic stroke.
• Grip strength assessment provides significant insights into functional deficits and recovery potential post-stroke.
• This measure can aid in tracking recovery and guiding rehabilitation strategies for stroke survivors.