Relationships Between Clinically Measured Upper-Extremity Physical Characteristics and Ball Spin Rate in Professional Baseball Pitchers

Background: The baseball-throwing motion requires a sequential order of motions and forces initiating in the lower limbs and transferring through the trunk and ultimately to the upper extremity. Any disruption in this sequence can increase the forces placed on subsequent segments. No research has examined if baseball pitchers with less lumbopelvic control are more likely to develop upper extremity injury than pitchers with more control. Purpose: To determine if baseball pitchers who sustain a chronic upper extremity injury have less lumbopelvic control before their injury compared with a group of pitchers who do not sustain an injury. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 49 asymptomatic, professional baseball pitchers from a single Major League Baseball organization participated. Lumbopelvic control was measured using an iPod-based digital level secured to a Velcro belt around each player’s waist to measure anteroposterior (AP) and mediolateral (ML) deviations (degrees) during single-leg balance with movement and static bridge maneuvers. During a competitive season, 22 of these pitchers developed upper extremity injuries, while the remaining 27 sustained no injuries. Separate 2-tailed t-tests were run to determine if there were significant differences in lumbopelvic control between groups ( P < .05). Results: There were no significant between-group differences for the stride leg (nondominant) during the bridge test in either the AP ( P = .79) or the ML ( P = .42) directions, or either direction during the drive leg bridge test ( P > .68). However, the injured group had significantly less lumbopelvic control than the noninjured group during stride leg balance in both the AP ( P = .03) and the ML ( P = .001) directions and for drive leg balance in both the AP ( P = .01) and the ML ( P = .04) directions. Conclusion: These results demonstrate that baseball pitchers with diminished lumbopelvic control, particularly during stride leg and drive leg single-leg balance with movement, had more upper extremity injuries than those with more control. Clinicians should consider evaluating lumbopelvic control in injury prevention protocols and provide appropriate exercises for restoring lumbopelvic control before returning athletes to competition after injury. Specific attention should be given to testing and exercises that mimic a single-limb balance task.

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The effects of shoulder laxity on upper extremity blood flow in professional baseball pitchers

Journal of Shoulder and Elbow Surgery ◽

10.1016/j.jse.2010.09.007 ◽

2011 ◽

Vol 20 (3) ◽

pp. 461-466 ◽

Cited By ~ 7

Author(s):

Steven C. Bast ◽

Fred A. Weaver ◽

Susana Perese ◽

Frank W. Jobe ◽

David C. Weaver ◽

...

Keyword(s):

Blood Flow ◽

Upper Extremity ◽

Professional Baseball ◽

Shoulder Laxity ◽

Baseball Pitchers

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Increased Shoulder Distraction Force and Shoulder Horizontal Abduction in Professional Baseball Pitchers With Discordant Torso Rotation Order

The American Journal of Sports Medicine ◽

10.1177/03635465211041381 ◽

2021 ◽

pp. 036354652110413

Author(s):

Joseph E. Manzi ◽

Brittany Dowling ◽

Joshua S. Dines ◽

Alexander Richardson ◽

Kathryn L. McElheny ◽

...

Keyword(s):

Upper Extremity ◽

Internal Rotation ◽

External Rotation ◽

Rotation Velocity ◽

Mean Difference ◽

Professional Baseball ◽

Pelvic Rotation ◽

Shoulder External Rotation ◽

Baseball Pitchers ◽

Distraction Force

Background: Inefficient energy transfer from the pelvis and trunk has been shown to increase compensation at the level of the shoulder. Kinetic chain sequencing of the core segments is underexamined in professional baseball pitchers, especially as it relates to changes in upper extremity kinetics. Purpose: To evaluate elbow and shoulder kinetics in a cohort of professional pitchers differentiated by instances of discordant pelvic to upper torso sequencing during the pitch. Study Design: Descriptive laboratory study. Methods: 285 professional baseball pitchers were evaluated using 3D motion capture (480 Hz). Pitchers were divided into “chronological” and “discordant” groups based on whether maximum pelvic rotation velocity occurred before (chronological) or after (discordant) maximum upper torso rotation velocity during the pitch motion. Pelvic, upper torso, and shoulder kinematic parameters, shoulder distraction force, shoulder internal rotation torque, and pitch efficiency (PE) were compared between groups. Results: Pitchers with discordant torso sequencing (n = 30; 110 pitches) had greater shoulder horizontal adduction at maximum external rotation (mean difference, 3.6°; 95% CI, −5.2° to −2.0°; t = −4.5; P < .001) and greater maximum shoulder external rotation (mean difference, 3.7°; 95% CI, 5.7° to 1.5°; t = −3.5; P < .001) than chronological pitchers (n = 255; 2974 pitches). PE did not differ between groups ( P = .856), whereas ball velocity was significantly faster in the discordant group (mean difference, 0.6 m/s; 95% CI, −1.1 to −0.3 m/s; t = −3.3; P = .0012). Chronological pitchers had significantly reduced shoulder distraction force (mean difference, −4.7% body weight (BW); 95% CI, −7.9% to −1.5% BW; t = −2.9; P = .004) with no difference in shoulder internal rotation torque ( P = .160). These kinematic and kinetic differences were not observed when accounting for interpitcher variability. Conclusion: Between pitchers, those who had a discordant pelvic to upper torso sequence experienced significantly greater shoulder distraction forces, potentially compensating by increasing maximum shoulder external rotation and horizontal abduction. Achieving maximal pelvic rotation velocity before maximal rotation velocity may be advantageous in preventing compensation at the upper extremity and excessive throwing arm loading. Clinical Relevance: Identifying risk factors for increased upper extremity forces has potential implications in injury prevention. Specifically, mitigating shoulder distraction forces may be beneficial in reducing risk of injury.

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Upper extremity blood flow changes in professional baseball pitchers between two consecutive seasons

Journal of Shoulder and Elbow Surgery ◽

10.1016/j.jse.2015.02.010 ◽

2015 ◽

Vol 24 (7) ◽

pp. 1069-1073 ◽

Cited By ~ 2

Author(s):

Kevin Laudner ◽

Noelle Selkow ◽

Nick Burke ◽

Keith Meister

Keyword(s):

Blood Flow ◽

Upper Extremity ◽

Professional Baseball ◽

Flow Changes ◽

Baseball Pitchers

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Pitching Mechanics and the Relationship to Accuracy in Professional Baseball Pitchers

The American Journal of Sports Medicine ◽

10.1177/03635465211067824 ◽

2022 ◽

pp. 036354652110678

Author(s):

Joseph E. Manzi ◽

Brittany Dowling ◽

Zhaorui Wang ◽

Andrew Luzzi ◽

Ryan Thacher ◽

...

Keyword(s):

Upper Extremity ◽

Internal Rotation ◽

Injury Risk ◽

Body Height ◽

Knee Extension ◽

High Accuracy ◽

Professional Baseball ◽

Significant Difference ◽

The Absolute ◽

Baseball Pitchers

Background: Biomechanical predictors of pitching accuracy are underevaluated in baseball research. It is unclear how pitchers with higher accuracy differ in terms of kinematics and upper extremity kinetics. Purpose: To differentiate high- and low-accuracy professional pitchers by full-body kinematic and upper extremity kinetic parameters. Study Design: Descriptive laboratory study. Methods: In total, 121 professional baseball pitchers threw 8 to 12 fastballs while assessed with motion-capture technology (480 Hz). Pitchers were divided into high-accuracy (n = 33), moderate-accuracy (n = 52), and low-accuracy (n = 36) groups based on the absolute center deviation of each pitcher’s average pitch to the center of the pitching chart by greater or less than 0.5 SD from the mean, respectively. The 95% confidence ellipses with comparisons of major and minor radii and pitching probability density grids were constructed. Analysis of variance was used to compare kinematic and kinetic values between groups. Results: The absolute center deviation (14.5% ± 6.7% vs 33.5% ± 3.7% grid width; P < .001) was significantly lower in the high-accuracy compared with the low-accuracy group, with no significant difference in ball velocity (38.0 ± 1.7 vs 38.5 ± 2.0 m/s; P = .222). Lead knee flexion at ball release (30.6°± 17.8° vs 40.1°± 16.3°; P = .023) was significantly less for the high-accuracy pitchers. Peak normalized shoulder internal rotation torque (5.5% ± 1.0% vs 4.9% ± 0.7% body weight [BW] × body height [BH]; P = .008), normalized elbow varus torque (5.4% ± 1.0% vs 4.8% ± 0.7% BW × BH; P = .008), and normalized elbow medial force (42.9% ± 7.3% vs 38.6% ± 6.2% BW; P = .024) were significantly greater for the low-accuracy group compared with the high-accuracy group. Conclusion: Professional pitchers with increased accuracy experienced decreased throwing arm kinetics. These pitchers had increased lead knee extension at later stages of the pitch, potentially providing more stable engagement with the ground and transference of kinetic energy to the upper extremities. Professional pitchers can consider increasing lead knee extension at the final stages of the pitch to improve the accuracy of their throws and mitigate elbow varus torque. Clinical Relevance: Increased elbow varus torque, shoulder internal rotation torque, and elbow medial force in less accurate pitchers may contribute to increased injury risk in this group.

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Early Cocking Phase Mechanics and Upper Extremity Surgery Risk in Starting Professional Baseball Pitchers

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967115581594 ◽

2015 ◽

Vol 3 (4) ◽

pp. 232596711558159 ◽

Cited By ~ 9

Author(s):

Wiemi A. Douoguih ◽

Donald L. Dolce ◽

Andrew E. Lincoln

Keyword(s):

Upper Extremity ◽

Professional Baseball ◽

Baseball Pitchers

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Correlation of Range of Motion and Glenohumeral Translation in Professional Baseball Pitchers

Yearbook of Sports Medicine ◽

10.1016/s0162-0908(08)70297-6 ◽

2006 ◽

Vol 2006 ◽

pp. 61-62

Author(s):

R.C. Cantu

Keyword(s):

Range Of Motion ◽

Professional Baseball ◽

Baseball Pitchers

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The Relationship between Scapular Upward Rotation and Shoulder Internal and External Rotation Isokinetic Strength in Professional Baseball Pitchers

Healthcare ◽

10.3390/healthcare9060759 ◽

2021 ◽

Vol 9 (6) ◽

pp. 759

Author(s):

Byung Gon Kim ◽

Seung Kil Lim ◽

Sunga Kong

Keyword(s):

External Rotation ◽

Professional Baseball ◽

Isokinetic Strength ◽

Strength Ratio ◽

Shoulder Injury ◽

Isokinetic Dynamometer ◽

Normal Range ◽

History Of ◽

Baseball Pitchers ◽

The Relationship

This study aims to assess the relationship between scapular upward rotation (SUR) across varying humeral-elevation angles (HEAs) and shoulder isokinetic strength and ratio in professional baseball pitchers. The subjects were professional baseball pitchers (n = 16) without a history of shoulder injury in the last six months. The subject’s SUR angles were measured with the humerus elevated at HEAs of 0° (at rest), 60°, 90°, and 120° to the scapular plane. Shoulder isokinetic strength was evaluated for shoulder internal rotation (IR) and external rotation (ER) strength (PT%BW and TW%BW), and the ER/IR strength ratios were determined at 60, 120 and 180°/s using an isokinetic dynamometer. The SUR angle at an HEA of 0° was positively correlated with IR strength at 120°/s (r = 0.535) and 180°/s (r = 0.522). The SUR angle at an HEA of 60° was negatively correlated with the ER/IR strength ratios at 60°/s (r = −0.505) and 120°/s (r = −0.500). The SUR angle at an HEA of 90° was negatively correlated with the ER/IR strength ratios at 60°/s (r = −0.574; r = −0.554) and 120°/s (r = −0.521; r = −0.589) as well as with ER strength at 180°/s (r = −0.591, r = −0.556). The SUR angle at an HEA of 120° was negatively correlated with ER strength at 60°/s (r = −0.558), 120°/s (r = −0.504; r = −0.524), and 180°/s (r = −0.543) and the ER/IR strength ratio at 60°/s (r = −0.517). In this study, we found that the ratio of isokinetic strength between ER and IR became closer to the normal range on increasing the SUR angle. In particular, an HEA of 90°, which resembles the pitching motion, showed a clear relationship between SUR, shoulder ER, and the ratio of ER/IR isokinetic strength in professional baseball pitchers.

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