Comparison of Pitching Motion of High School Baseball Pitchers

Background: Understanding the relationship between the temporal phases of the baseball pitch and subsequent joint loading may improve our understanding of optimal pitching mechanics and contribute to injury prevention in baseball pitchers. Purpose: To investigate the temporal phases of the pitching motion and their associations with ball velocity and throwing arm kinetics in high school (HS) and professional (PRO) baseball pitchers. Study Design: Descriptive laboratory study. Methods: PRO (n = 317) and HS (n = 54) baseball pitchers were evaluated throwing 8 to 12 fastball pitches using 3-dimensional motion capture (480 Hz). Four distinct phases of the pitching motion were evaluated based on timing of angular velocities: (1) Foot-Pelvis, (2) Pelvis-Torso, (3) Torso-Elbow, and (4) Elbow-Ball. Peak elbow varus torque, shoulder internal rotation torque, and shoulder distraction force were also calculated and compared between playing levels using 2-sample t tests. Linear mixed-effect models with compound symmetry covariance structures were used to correlate pitch velocity and throwing arm kinetics with the distinct temporal phases of the pitching motion. Results: PRO pitchers had greater weight and height, and faster ball velocities than HS pitchers ( P < .001). There was no difference in total pitch time between groups ( P = .670). PRO pitchers spent less time in the Foot-Pelvis ( P = .010) and more time in the Pelvis-Torso ( P < .001) phase comparatively. Shorter time spent in the earlier phases of the pitching motion was significantly associated with greater ball velocity for both PRO and HS pitchers (Foot-Pelvis: B = −6.4 and B = −11.06, respectively; Pelvis-Torso: B = −6.4 and B = −11.4, respectively), while also associated with increased shoulder proximal force (Pelvis-Torso: B = −76.4 and B = −77.5, respectively). Decreased time in the Elbow-Ball phase correlated with greater shoulder proximal force for both cohorts (B = −1150 and B = −645, respectively) with no significant correlation found for ball velocity. Conclusion: Significant differences in temporal phases exist between PRO and HS pitchers. For all pitchers, increased time spent in the final phase of the pitching motion has the potential to decrease shoulder distraction force with no significant loss in ball velocity. Clinical Relevance: Identifying risk factors for increased shoulder and elbow kinetics, acting as a surrogate for loading at the respective joints, has potential implications in injury prevention.

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Four-year trend in shoulder and elbow injuries in competitive level high school baseball pitchers: A repeated cross-sectional survey

JSES International ◽

10.1016/j.jseint.2021.04.006 ◽

2021 ◽

Author(s):

Tsuyoshi Sasaki ◽

Hitoshi Shitara ◽

Tsuyoshi Tajika ◽

Takuro Kuboi ◽

Tsuyoshi Ichinose ◽

...

Keyword(s):

High School ◽

Cross Sectional Survey ◽

Cross Sectional ◽

Elbow Injuries ◽

Baseball Pitchers

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An analysis of pre-season risk factors for low back injury in high-school baseball pitchers: a prospective study

Scientific Reports ◽

10.1038/s41598-021-90988-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kurumi Nakase ◽

Hitoshi Shitara ◽

Tsuyoshi Tajika ◽

Takuro Kuboi ◽

Tsuyoshi Ichinose ◽

...

Keyword(s):

High School ◽

Shoulder Function ◽

Whole Body ◽

Back Injury ◽

Low Back ◽

Shoulder Range Of Motion ◽

Low Back Injury ◽

Significant Independent Risk Factor ◽

Elbow Injuries ◽

Baseball Pitchers

AbstractPitching motion requires whole-body coordination; therefore, poor control of the lower extremities, pelvis and trunk may cause shoulder and elbow injuries. However, few studies have described the relationship between the shoulder joint function and low back injury in high-school baseball pitchers. A total of 128 healthy high school pitchers underwent pre-season medical checkups, where their shoulder range of motion and shoulder strength were measured. The participants completed a self-recorded daily questionnaire regarding the presence of low back pain. Pitchers were divided into injured and non-injured groups. Low back injury was observed in 13 participants (13.4%). In the injured group, horizontal adduction on the dominant shoulder was significantly less than in the non-injured group. A logistic regression analysis showed that horizontal adduction on the dominant side was a significant independent risk factor for low back injury during the season. It is important to recognize that restriction of the shoulder function not only causes shoulder and elbow injuries but can also risk low back injury.

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Daily Players’ Satisfaction with Pitching Performance Could Predict Shoulder and Elbow Injuries in High-school Baseball Pitchers: A Prospective Time-to-event Study

10.21203/rs.3.rs-163670/v1 ◽

2021 ◽

Author(s):

Hitoshi Shitara ◽

Tsuyoshi Tajika ◽

Takuro Kuboi ◽

Tsuyoshi Ichinose ◽

Tsuyoshi Sasaki ◽

...

Keyword(s):

High School ◽

Event Study ◽

Operating Characteristics ◽

Time To Event ◽

Elbow Injury ◽

Shoulder Range Of Motion ◽

Elbow Injuries ◽

Characteristics Analysis ◽

Baseball Pitchers ◽

The Relationship

Abstract The relationship between baseball pitchers’ satisfaction with their own performance and the incidence of shoulder and elbow injuries is unclear. We analyzed the relationship between daily satisfaction scores before injury and incidence of shoulder/elbow injury in high-school baseball pitchers in this prospective, time-to-event study. We collected baseline data on baseball experience, height, weight, elbow and shoulder range of motion, and shoulder muscle strength. The 108 enrolled participants aged 15-17 years were divided into satisfied (88) and unsatisfied (22) groups based on the Receiver operating characteristics analysis results that revealed the cutoff value to be 4 points. The incidence of injury was 10.2% and 50.0% in the satisfied and unsatisfied groups, respectively. We observed that high-school baseball pitchers with a low satisfaction significantly increased the risk of shoulder and elbow injuries: these players had a 7.3-times greater risk of injuries and a 1.9-times earlier occurrence of injuries than pitchers who are satisfied with their performance. High-school baseball pitchers who had low satisfaction with their pitching performance had higher risk of shoulder and elbow injuries and lower time to injury than satisfied pitchers. Daily evaluation of players’ self-satisfaction could predict shoulder and elbow injuries in high-school baseball pitchers.

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Relationship between tightness of the hip joint and shoulder/elbow injury in high school baseball pitchers: a prospective study

Scientific Reports ◽

10.1038/s41598-020-76894-6 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Noritaka Hamano ◽

Hitoshi Shitara ◽

Tsuyoshi Tajika ◽

Tsuyoshi Ichinose ◽

Tsuyoshi Sasaki ◽

...

Keyword(s):

High School ◽

Risk Factor ◽

Lower Limb ◽

External Rotation ◽

Elbow Pain ◽

Elbow Injury ◽

Hip Range Of Motion ◽

Baseball Pitchers ◽

A Prospective Study ◽

The Relationship

AbstractSome studies have reported that upper limb tightness is a risk factor for shoulder/elbow pain in high school baseball pitchers; but there has been insufficient research on the relationship between lower limb tightness and shoulder and elbow pain in pitchers. This study aimed to clarify the correlation among pre-season hip range of motion (ROM) and shoulder and elbow disorders in high school baseball pitchers. We surveyed 125 high school pitchers. Hip ROM was measured in the supine and prone positions. After the season, based on their answers to the self-recorded questionnaire, a “shoulder or elbow injury” was defined as any condition resulting in the pitcher being considered disabled for ≥ 8 days. An independent t-test and logistic regression analysis were used for statistical analysis. Eleven disabled pitchers (9%) were identified during the season. In the injured group, the ROM of the plant side hip with 90° flexed external rotation was smaller than that in the non-injured group. Preseason limited ROM in the plant side hip with 90° flexed external rotation was a risk factor for the occurrence of shoulder/elbow pain in the season.

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Effects of Mound Versus Flat-Ground Pitching and Distance on Arm Mechanics and Elbow Torque in High School Pitchers

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967120969245 ◽

2020 ◽

Vol 8 (12) ◽

pp. 232596712096924

Author(s):

Brittany Dowling ◽

Kathryn D. McElheny ◽

Christopher L. Camp ◽

Daphne I. Ling ◽

Joshua S. Dines

Keyword(s):

High School ◽

Mixed Effects Models ◽

Multivariable Model ◽

Linear Mixed Effects ◽

Study Results ◽

Ball Velocity ◽

Surrogate Measure ◽

Baseball Pitchers ◽

The Impact ◽

Flat Ground

Background: Although the monitoring of a pitcher’s throwing arm workload has become a hot topic in both research and the pitching world, the impact of mound height and distance still remains unclear. Purpose: To compare the kinetics and kinematics between pitches from a mound and flat ground at 2 different distances. Study Design: Descriptive laboratory study. Methods: A total of 21 healthy high school varsity baseball pitchers (age, 16.2 ± 1.3 years; weight, 73.6 ± 11.0 kg; height, 181.3 ± 6.4 cm) participated in this study. Players were fitted with a motusBASEBALL sensor and sleeve. Each pitcher was instructed to pitch 5 fastballs under 4 conditions: mound at 60.5 ft (regulation distance), flat ground at 60.5 ft, mound at 50.5 ft, and flat ground at 50.5 ft. Linear mixed-effects models were used to account for both intra- and interplayer variability. A multivariable model was used to evaluate the association of mound pitching, flat-ground pitching, and their distances (50.5 ft and 60.5 ft), and their interaction to arm speed, arm slot, arm rotation, elbow varus torque, and ball velocity. Results: There were no statistically significant effects of mound, flat-ground, or distance variation on arm speed or shoulder rotation. Arm slot was significantly higher (+3.0°; P = .02) on pitches from the mound at 60.5 ft compared with 50.5 ft. Elbow varus torque was lower (–1.5 N·m; P = .02) on mound pitches at 60.5 ft compared with 50.5 ft. Pitches thrown from the mound displayed significantly faster ball velocity compared with flat-ground pitches at both distances ( P < .01 for both), with pitches at 60.5 ft having higher velocity (+0.7 m/s; P < .01). Conclusion: Contrary to long-standing notions, the study results suggest that pitching from the mound does not significantly increase stress on the elbow compared with flat-ground pitching. Lower elbow varus torque and faster ball velocity at the regulation distance compared with the reduced distance indicate that elbow stress and ball velocity may not correlate perfectly, and radar guns may not be an appropriate surrogate measure of elbow varus torque. Clinical Relevance: A better understanding of the kinetic and kinematic implications of various throwing programs will allow for the designing of programs that are driven by objective data with aims directed toward injury prevention and rehabilitation in baseball pitchers.

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