Professional Baseball Player Type and Geographic Region of Origin Impacts Shoulder External and Internal Rotation Strength

Context:Posterior shoulder tightness has been associated with altered shoulder range of motion (ROM) and several pathologic entities in baseball players. This tightness is hypothesized to be the result of the cumulative stress placed on the posterior shoulder during the deceleration phase of the throwing motion. The role of the posterior shoulder static restraints is to absorb this load while the glenohumeral (GH) external rotators eccentrically decelerate the arm after ball release and therefore also help dissipate this force. As such, the authors hypothesized that if the GH external rotators are weak, an excessive amount of this deceleration force is placed on the static restraints, which may lead to subsequent tightness.Objective:To compare the relationship between GH external-rotation strength and posterior shoulder tightness as measured by GH horizontal-adduction and internal-rotation ROM.Design:Descriptive study.Setting:Laboratory.Participants:45 professional baseball players.Main Outcome Measures:GH external-rotation strength and GH horizontal-adduction and internalrotation ROM.Results:GH external-rotation strength showed no relationship with either GH horizontal-adduction ROM (r2 = .02, P = .40) or GH internal-rotation ROM (r2 = .002, P = .77).Conclusion:There is little to no relationship between GH external-rotation strength and posterior shoulder tightness in professional baseball players. The posterior static restraints of the shoulder may absorb a large majority of the deceleration forces during the throwing motion. Although strengthening of the posterior shoulder dynamic restraints should not be overlooked, routine stretching of the static restraints may be more beneficial for decreasing posterior shoulder tightness and the subsequent risks associated with this tightness, although future research is warranted.

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Ulnar-Sided Digital Nerve Tumor of the Thumb in the Professional Baseball Player Who Uses Grip-Adjusting Batting Equipment: A Report of 2 Cases

The Journal Of Hand Surgery ◽

10.1016/j.jhsa.2020.10.028 ◽

2021 ◽

Author(s):

John Pinski ◽

Michael Guss ◽

Nicholas Coccoluto ◽

Peter Asnis ◽

Matthew Leibman

Keyword(s):

Professional Baseball ◽

Baseball Player ◽

Digital Nerve ◽

Nerve Tumor

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Relationship between Glenohumeral Internal Rotation Deficit and Shoulder Conditions in Professional Baseball Pitchers

Journal of Shoulder and Elbow Surgery ◽

10.1016/j.jse.2020.10.041 ◽

2020 ◽

Author(s):

Kohei Yamaura ◽

Yutaka Mifune ◽

Atsuyuki Inui ◽

Hanako Nishimoto ◽

Takashi Kurosawa ◽

...

Keyword(s):

Internal Rotation ◽

Professional Baseball ◽

Glenohumeral Internal Rotation Deficit ◽

Baseball Pitchers

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Hip external and internal rotation strength: Consistency over time and between sides

Isokinetics and Exercise Science ◽

10.3233/ies-2008-0304 ◽

2008 ◽

Vol 16 (2) ◽

pp. 107-111 ◽

Cited By ~ 2

Author(s):

Richard W. Bohannon ◽

Jeremy Vigneault ◽

Jon Rizzo

Keyword(s):

Internal Rotation ◽

Rotation Strength ◽

Over Time

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The influence of testing positions and resistance locations on muscle activities during shoulder internal rotation strength measurements in young healthy adults

Journal of Orthopaedic Science ◽

10.1016/j.jos.2021.08.004 ◽

2021 ◽

Author(s):

Yu Ito ◽

Hisashi Matsumoto ◽

Tomoya Ishida ◽

Shota Shimizu ◽

Naomi Oizumi ◽

...

Keyword(s):

Internal Rotation ◽

Healthy Adults ◽

Rotation Strength

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An Interview with Jim Eisenreich

CNS Spectrums ◽

10.1017/s109285290000078x ◽

1999 ◽

Vol 4 (3) ◽

pp. 18-20

Author(s):

Mark L. Fuerst

Keyword(s):

Los Angeles ◽

Tourette Syndrome ◽

Role Model ◽

Correct Diagnosis ◽

Professional Baseball ◽

Baseball Player ◽

Team Physician ◽

Professional Athlete ◽

Minor Leagues

Seventeen years after professional baseball player Jim Eisenreich first developed symptoms of Tourette syndrome (TS), the correct diagnosis was finally made.At age 6, his rapid eye blinking led to a diagnosis of hyperactivity. “I was told I would grow out of it,” says the 39-year-old Eisenreich, who may have played his last game as a Los Angeles Dodger. “I knew I was different even then.”In the early 1980s, Eisenreich's condition first became public. Since then, his achievements as a professional athlete have made him a role model for other TS patients.Sports were always a haven for him as he grew up. “I found peace, comfort, and security in sports. Whatever the season, I played the sport—football, baseball, hockey,” says Eisenreich. “Socially, I didn't go to the movies or go out much with girls.”After 2 years in the minor leagues, he was called up by the Minnesota Twins in 1982 as an outfielder. During the season, a TS specialist recognized his grunting and sniffling as signs of the disease. “I had no idea what the specialist was talking about, and the Twins doctors dismissed it because I didn't have copralalia,” he says. The Twins team physician (an internist) prescribed a sedative. Then Eisenreich tried Inderal, which caused hyperventilation, and Catapres, which caused depression.

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Shoulder Rotation Function following the Sup-ER Protocol in Children with Brachial Plexus Injuries

Hand ◽

10.1177/1558944720937365 ◽

2020 ◽

pp. 155894472093736

Author(s):

Leeor S. Yefet ◽

Doria Bellows ◽

Marija Bucevska ◽

Rebecca Courtemanche ◽

Kim Durlacher ◽

...

Keyword(s):

Cohort Study ◽

Brachial Plexus ◽

Range Of Motion ◽

Internal Rotation ◽

External Rotation ◽

Cross Sectional ◽

Elbow Function ◽

Rotation Strength ◽

Rotation Function

Background: Our group previously developed an upper extremity repositioning (Sup-ER) protocol for brachial plexus birth injuries (BPBIs) that may improve supination and external rotation (ER) at 2 years of age. Questions were raised about the potential for the protocol to cause internal rotation (IR) deficits. The goal of this study was to explore the longer-term outcomes of the Sup-ER protocol and investigate IR/ER function. Methods: This prospective cross-sectional cohort study examined 16 children older than 4 years of age with significant enough BPBI to be treated with the Sup-ER protocol. Total shoulder and elbow function were assessed, including passive and active ranges of motion and strength of IR and ER. Results: Range of motion (ROM) for most active movements was decreased in the affected compared to unaffected arm. Notably, IR passive ROM was similar in the affected (78.7°) and unaffected arm (82.8°). External rotation strength of the affected arm was weaker (42.8 N) compared to the unaffected arm (57.9 N). IR strength had a greater deficit in the affected (43.2 N) arm compared to the unaffected arm (72.2 N), but both ER and IR showed less deficit than described in the literature. Conclusions: Despite differences in ranges of motion between the affected and unaffected arms, ROMs for the affected arm were comparable to the functional limits as reported in the literature. The Sup-ER protocol shows potential to optimize long-term shoulder rotation function in children with BPBI without compromising IR.

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