Relationship of hand strength with paretic upper extremity function and activities of daily living performance in patients with subacute stroke

BACKGROUND: Muscle weakness is the most common impairment in the upper extremity (UE) after a stroke. Understanding the relationship between hand strength and functional outcomes would be advantageous in clinical settings for the development of efficient rehabilitation programs. PURPOSE: To determine the relationship of hand strength with paretic UE function and activities of daily living (ADL) performance. METHODS: Twenty-six patients with hemiparetic stroke (mean age 51.38±12.64 years) participated in this cross-sectional study. Hand strength was assessed on both the more affected and less affected sides. An electronic dynamometer and isokinetic dynamometer were used to measure static grip and pinch strength, and dynamic grip strength, respectively. The relationships of hand strength with paretic UE function (Fugl-Meyer Motor Assessment, FMA) and ADL performance (Modified Barthel Index, MBI) were analyzed. RESULTS: Hand strength on the more affected side had a moderate to high correlation with UE function (r=0.62-0.77, P<0.001), in comparison hand strength on the less affected side had low correlation with UE function (r=0.39-0.44, P<0.05). Hand strength on the less affected side had a moderate to high correlation with ADL performance (r=0.61-0.75, P<0.001), while, hand strength on the more affected side had low correlation with ADL performance (r=0.42; P=0.03). Regression analysis showed that static grip and pinch strength on the more affected side contributed 71% of the variance in FMA scores, and static grip and pinch strength on the less affected side accounted for 73% of the variance in MBI scores. CONCLUSION: Hand strength on the more affected side is associated with paretic UE function and hand strength on the less affected side is associate with ADL performance.