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The instant of foot contact is an important transition point during the pitch cycle between the linear portion of the pitch, as a pitcher strides down the mound and the rotational portion of the pitch. Understanding the implications of lead foot angle at foot contact is an essential information needed to assist pitching coaches in their work with individual pitchers. Therefore, the purpose of this study was to determine the association between lead foot progression angle at foot contact and ball velocity, elbow varus moment, and pelvic rotation. Kinematic and kinetic data were collected from 99 collegiate pitchers and analyzed using a random intercept, mixed-effects regression model. Significant associations were found between lead foot progression angle at foot contact and elbow varus moment (P =.004), as well as pelvic rotation throughout the pitching motion (P <.001). The data indicate that increased lead foot internal rotation at foot contact is associated with increases in the elbow varus moment but is not associated with ball velocity. This study provides scientific evidence that the rotational positioning of the lead foot can affect both pelvic motion and upper-extremity joint moments. [ABSTRACT FROM AUTHOR]

Researchers have postulated that the rise in the incidence of pitching injuries is partially due to poor pitching mechanics. A topic that is often debated revolves around the correct positioning of the elbow in relationship to the body. Therefore, this study attempts to understand the associations of vertical or horizontal elbow positon with upper extremity joint moments, and ball velocity, and how elbow position is influenced by trunk position. Motion analysis data from 99 collegiate pitchers were analysed for this study. A random intercept, mixed-effects regression model was used to determine if statistically significant associations existed between elbow position and upper extremity joint moments and ball velocity. Results indicated that visual impressions of the elbow position were highly correlated with trunk position, whereas kinematic definitions of elbow position were correlated to the glenohumeral angle. Visual vertical and horizontal elbow position was associated with increased elbow varus moments (p = 0.001) and ball velocity (p = 0.019), respectively. Whereas kinematic elbow position was not associated with either upper extremity joint moments or ball velocity. Therefore, what coaches visually interpret as an improperly positioned elbow may actually be a combination of lateral lean, anterior tilt, and over rotation of the trunk. [ABSTRACT FROM AUTHOR]

The incidence of elbow injury experienced by baseball pitchers is on the rise. Biomechanical investigations focusing on the acceleration phase of the pitch have yet to elucidate a singular cause for these injuries. Leading to the question is there an additional significant stress on the elbow during other phases of the pitch? This study sought to determine the magnitude of the elbow varus moment during the deceleration phase of the pitching cycle for the fastball, curveball, slider and change-up. Eighty-seven collegiate-level pitchers were evaluated using motion analysis techniques to determine the magnitude of the elbow varus moment occurring during the deceleration phase. The results indicated that the elbow varus moment during the deceleration phase of the pitch was typically between 40% and 50% of the peak acceleration phase moment and was greatest when throwing a slider. Results also indicated that more pitchers experienced deceleration phase moments in excess of 50% of the acceleration moment when throwing breaking pitches. These moments which are the result of the pitchers' need to rapidly decelerate their arm produce an additional significant elbow varus moment that results in additional stress to the elbow. [ABSTRACT FROM AUTHOR]

Background: The incidence of upper extremity injury in baseball pitchers has increased over the past decade. This has resulted in a large body of research mainly focused on the kinematic and kinetic patterns of the elbow and shoulder to elucidate the cause of these injuries, with little attention on studying the associations of forearm rotation and upper arm joint moments. Hypothesis: There will be significant differences in forearm kinematics and kinetics when comparing the fastball pitch with the curveball pitch. There will be a positive association between forearm kinetics, specifically supination and pronation moments, and the elbow varus moment. Study Design: Descriptive laboratory study. Methods: A total of 78 pitchers were recruited for this study, and they underwent a pitching analysis using motion analysis techniques. A random-intercept, mixed-effects regression model was used to determine differences in forearm kinematics and kinetics when pitching a fastball compared with a curveball, as well as to determine if associations existed between forearm supination and pronation moments and the elbow varus moment. Results: There were a number of significant differences in forearm position when pitching a fastball compared with a curveball, with the curveball producing a more supinated forearm position. Significant associations were found between increasing forearm supination moments and an increase in elbow varus moment for both the fastball and the curveball (P = .002 and P < .001, respectively). For every 1-N·m increase in the supination moment, there was a 1-N·m and 1.1-N·m increase in the elbow varus moment for the fastball and curveball, respectively. Conclusion: The results demonstrated that the forearm position was not associated with the elbow varus moment. However, the supination moment was associated with the elbow varus moment. Clinical Relevance: On the basis of these findings, pitching coaches and trainers can understand the implications of proper lower arm pitching mechanics in the later portion of the pitch cycle as a potential risk of injury and, therefore, can develop coaching strategies to reduce incorrect positioning, especially when players are pitching the curveball. [ABSTRACT FROM AUTHOR]

Left-handed baseball pitchers are thought to have a number of theoretical advantages compared to right-handed pitchers; however, there is limited scientific research detailing differences in the pitching mechanics of right- and left-handed pitchers. Therefore, this study sought to understand whether any kinematic and kinetic differences existed between right- and left-handed baseball pitchers. A total of 52 collegiate pitchers were included in this study; 26 left-handed pitchers were compared to 26 age-, height-, weight- and ball velocity-matched right-handed pitchers. Demographic information, passive shoulder range of motion and kinematic and kinetic data were obtained for each pitcher participating in the study. Results indicated that left-handed pitchers did not have a glenohumeral internal rotation deficit as compared to right-handed pitchers. Kinematic analysis indicated that elbow flexion, horizontal glenohumeral abduction and wrist coronal plane motion were significantly different between the two study cohorts. It was also noted that left-handed pitchers had increased elbow varus moments. The findings of this study suggest that pitching coaches should be aware that there are biomechanical differences between left- and right-handed pitchers. [ABSTRACT FROM AUTHOR]

Background: The incidence of upper extremity injuries in baseball pitchers is increasing. Over the past decade there has been a great deal of research attempting to elucidate the cause of these injuries, focusing mainly on the mechanics of the pitching arm with no examination of other key segments, such as the trunk. This is surprising, as coaches will often comment on trunk position in an effort to improve pitching outcomes. Purpose: To determine the association between contralateral trunk lean and ball velocity and the moments about the elbow and glenohumeral joint. Study Design: Descriptive laboratory study. Methods: A total of 99 pitchers were recruited for this study and underwent a pitching analysis using 3-dimensional motion analysis techniques. A random intercept mixed-effects regression model was used to determine if statistically significant associations existed between contralateral trunk lean (away from the pitching arm side) and ball velocity, as well as the elbow varus moment and glenohumeral internal rotation moment. Results: The results demonstrated that the greatest contralateral trunk lean occurs around the time of the peak elbow varus moment. Statistically significant associations were found between contralateral trunk lean and increased ball velocity (P = .003) indicating that for every 10 increase in contralateral lean, ball velocity increased 0.5 m/s. Results also indicated that for every 10 increase in contralateral lean, elbow varus moments increased by 3.7 Nm and glenohumeral internal rotation moments increased by 2.5 Nm (P \ .001 for both). Conclusion: Study findings indicate that the positioning of the trunk plays a substantial role in pitching performance and pitcher injury potential. This work helps to demonstrate the importance of proper trunk mechanics in pitching and highlights the need for future research to understand the contribution of the trunk to pitching mechanics. Clinical Relevance: Pitching coaches and trainers can use the results of this study to stress the importance of proper trunk mechanics in pitching. Specifically, improving core strength and trunk control in an effort to maintain a more upright posture through the pitching cycle can reduce upper extremity joint stresses. [ABSTRACT FROM AUTHOR]