In the JournalsPerspective

Internal rotation loss, external rotation gain may increase medial UCL injury risk in pitchers

Rafael Escamilla
Rafael F. Escamilla

Results showed glenohumeral internal rotation loss, glenohumeral external rotation gain and total rotational motion deficit may be related to increased medial ulnar collateral ligament injury risk among baseball pitchers.

Rafael F. Escamilla, PhD, PT, CSCS, and colleagues matched 108 male high school, college and professional baseball pitchers with medial UCL injury with 108 baseball pitchers without medial UCL injury according to number, level of play and age. Researchers measured bilateral shoulder passive internal rotation/external rotation and calculated glenohumeral internal rotation loss, glenohumeral external rotation gain, total rotational motion and total rotational motion deficit.

Results showed pitchers with medial UCL injury had more glenohumeral internal rotation loss, glenohumeral external rotation gain and total rotational motion deficit. Researchers found a glenohumeral internal rotation loss greater than 18° in approximately 60% of pitchers in the medial UCL injury group vs. approximately 30% of pitchers in the control group for all pitching levels. Approximately 60% of pitchers in the medial UCL injury group and approximately 50% of pitchers in the control group had total rotational motion deficit greater than 5°, according to results. For glenohumeral internal rotation loss, glenohumeral external rotation gain, total rotational motion deficit and throwing shoulder external rotation, internal rotation and total rotational motion, researchers found no differences among high school, college and professional pitchers.

“Greater [glenohumeral internal rotation loss] GIRLoss and [total rotational motion deficit] TRMD in [medial UCL] MUCL-injured pitchers compared to uninjured pitchers implies these variables may be related to increased MUCL injury risk, especially since GIRLoss greater than 18° and TRMD greater than 5° demonstrate an increased MUCL injury risk,” Escamilla told Healio.com/Orthopedics. “Shoulder rotational motion and deficits do not vary among [high school] HS, [college] COLL and [professional] PRO levels of pitchers.” – by Casey Tingle

 

Disclosures: The authors report no relevant financial disclosures.

Rafael Escamilla
Rafael F. Escamilla

Results showed glenohumeral internal rotation loss, glenohumeral external rotation gain and total rotational motion deficit may be related to increased medial ulnar collateral ligament injury risk among baseball pitchers.

Rafael F. Escamilla, PhD, PT, CSCS, and colleagues matched 108 male high school, college and professional baseball pitchers with medial UCL injury with 108 baseball pitchers without medial UCL injury according to number, level of play and age. Researchers measured bilateral shoulder passive internal rotation/external rotation and calculated glenohumeral internal rotation loss, glenohumeral external rotation gain, total rotational motion and total rotational motion deficit.

Results showed pitchers with medial UCL injury had more glenohumeral internal rotation loss, glenohumeral external rotation gain and total rotational motion deficit. Researchers found a glenohumeral internal rotation loss greater than 18° in approximately 60% of pitchers in the medial UCL injury group vs. approximately 30% of pitchers in the control group for all pitching levels. Approximately 60% of pitchers in the medial UCL injury group and approximately 50% of pitchers in the control group had total rotational motion deficit greater than 5°, according to results. For glenohumeral internal rotation loss, glenohumeral external rotation gain, total rotational motion deficit and throwing shoulder external rotation, internal rotation and total rotational motion, researchers found no differences among high school, college and professional pitchers.

“Greater [glenohumeral internal rotation loss] GIRLoss and [total rotational motion deficit] TRMD in [medial UCL] MUCL-injured pitchers compared to uninjured pitchers implies these variables may be related to increased MUCL injury risk, especially since GIRLoss greater than 18° and TRMD greater than 5° demonstrate an increased MUCL injury risk,” Escamilla told Healio.com/Orthopedics. “Shoulder rotational motion and deficits do not vary among [high school] HS, [college] COLL and [professional] PRO levels of pitchers.” – by Casey Tingle

 

Disclosures: The authors report no relevant financial disclosures.

    Perspective
    Mark Schickendantz

    Mark Schickendantz

    This represents the best study to date on the subject of the relationship between shoulder range of motion and medial UCL injury. The data suggest that excessive loss of glenohumeral internal rotation, excessive gain of external rotation and excessive loss of total range of motion are correlated to an increased risk of medial UCL injury in baseball pitchers at the high school, college and professional level. The fact that the authors found no significant differences in any motion measurement across these three groups suggests that these changes in range of motion occur at a young age. 

    The value of these types of studies is in the clinical utility of the data. We don’t know how much of the change in motion in the thrower’s shoulder is attributable to bone and/or soft tissue and thus, can’t say how modifiable these changes might be. Nonetheless, it seems important that players be aware that these motions should be monitored and an effort should be made to at least maintain the motion that they have.

    • Mark Schickendantz, MD
    • Director
      Cleveland Clinic Sports Health Center
      Garfield Heights, Ohio

    Disclosures: Schickendantz reports no relevant financial disclosures.