Strong Correlation of Upper-Extremity Blood-Flow Volume With Grip Strength While in a Provocative Shoulder Position in Baseball Pitchers

Abstract

Context:Baseball players, specifically pitchers, with symptomatic neurovascular occlusion often initially complain of arm fatigue and loss of ball control and velocity. As the compression continues complaints may manifest in dull pain, paresthesia, and decreased grip strength.Objective:To determine the correlation between upper-extremity blood-flow volume and grip strength among baseball pitchers.Design:Cross-sectional.Setting:Athletic training room.Participants:66 professional baseball pitchers (age 21.6 ± 2.0 y, height 186.9 ± 5.7 cm, mass 91.3 ± 10.9 kg) before the start of spring training.Main Outcome Measures:Diagnostic ultrasound was used to measure upper-extremity blood-flow volume with the throwing shoulder in a resting position and in a provocative position. Grip strength was measured with participants seated and their throwing-arm elbow flexed to 90°. Pearson product–moment correlation coefficients were used to determine the strength of the relationships between blood-flow volume in the 2 arm positions and grip strength (P < .05).Results:No significant relationship was found between blood-flow volume in the resting position and grip strength (r = .03, P = .81); however, a strong positive correlation was found in the 2nd provocative position (r = .67, P = .001). This relationship indicates that as blood-flow volume tested in a provocative shoulder position decreases, so does grip strength.Conclusion:A strong positive relationship was found in pitchers, demonstrating that as upper-extremity blood-flow volume while in the provocative shoulder position decreases, so does grip strength.