Collegiate Pitchers Research Articles

Pitching kinematics have direct and indirect effects on pitch location in NCAA baseball.

Kinematics and release parameters are important factors of throw location, yet an understanding of their relationship has yet to be achieved. This study sought to explore this relationship. Kinematic data were collected for seventy-seven collegiate pitchers. Fifty-seven kinematic parameters were included in path analyses for horizontal (HPL) and vertical plate locations (VPL). Release angles were set as mediating variables (MED) between independent (IV) and dependent (DV) variables. Eleven kinematic variables directly (13 indirectly) affected VPL, while 23 directly affected HPL (10 indirectly). Linear mixed models revealed that lateral trunk flexion at ball release (BR) (R2=.908, BIC=-598, ICC=.528) best explained VPL. Trunk flexion at foot contact (FC) (R2=.944, BIC=-607, ICC=.776), mediolateral centre of mass (COM) displacement at FC (R2=.974, BIC=-573, ICC=.918), and BR (R2=.967, BIC=-593, ICC=.865), and pelvis rotation at BR (R2=.965, BIC=-588, ICC=.895) models were identified for HPL. Results indicate the relationship between pitching kinematics, release conditions, and throw location is complex. Biomechanics can influence release parameters, which in turn impacts throw location. This work may serve to understand better how biomechanics influence performance.

Peak Lower-Extremity Power Unadjusted for Body Mass Predicts Fastball Velocity in Collegiate Baseball Pitchers.

King, BW, Snow, TK, and Millard-Stafford, M. Peak lower-extremity power unadjusted for body mass predicts fastball velocity in collegiate baseball pitchers. J Strength Cond Res XX(X): 000-000, 2024-The relationship between lower-extremity power production and fastball velocity in collegiate pitchers remains unclear. This study aimed to evaluate the relationship between lower-extremity power and throwing velocity in 33 National Collegiate Athletic Association Division I baseball pitchers. Lower-extremity power was quantified using countermovement jump (CMJ) testing on force plates and the Wingate anaerobic cycling test. In-game fastball velocities were collected using TrackMan technology. Pearson correlations and linear regressions were used to evaluate the association between lower-body power and fastball velocity. The strongest predictor of peak fastball velocity was body mass ( r = 0.58, p = 0.0004), followed by lean mass ( r = 0.52, p = 0.002). Peak power (W) produced on the Wingate and CMJ tests were each statistically significant predictors of peak velocity ( r = 0.44, p = 0.011; r = 0.43, p = 0.014, respectively), but CMJ power relative to body mass ( r = 0.19), jump height ( r = 0.07), and Sparta Scores ( r = -0.06) were not ( p > 0.05). Linear regression indicated Wingate and CMJ absolute peak power tests each independently explained 19% of the variance in fastball velocity but added little to the model when combined with body mass (∼34 vs. 32% of total variance). Because total body mass and lower-body power are important predictors of pitching velocity, absolute power output is a more relevant predictor of baseball pitching velocity than lower-body power variables influenced by body mass (e.g., jump height and Sparta Score).

Tall and Fall Versus Drop and Drive Strategy in College Baseball Pitchers for Velocity and Elbow Valgus Torque

Background: Depending on anthropometrics and coaching style, pitchers are taught to pitch with a stride strategy that are traditionally classified as “tall and fall” or “drop and drive” for the purpose of maximizing pitch velocity. Purpose/Hypothesis: The purpose of this study was to determine the effects of stride strategy (tall and fall vs drop and drive) in college baseball pitching on pitch velocity and elbow valgus torque. It was hypothesized that pitch velocity and elbow valgus torque would increase as pitchers aligned more with the tall and fall technique. Study Design: Controlled laboratory study. Methods: Markerless motion capture data were recorded on 64 collegiate pitchers (height, 1.89 ± 0.06 m; weight, 93.06 ± 9.44 kg) during game play at the host institution during the 2023 season. Peak magnitudes of body center of mass (COM) vertical displacement were determined using a straight-line trajectory between peak knee height and lead foot contact and used as a continuous variable. Pitchers were required to throw ≥4 fastballs during their outing to be included in the analysis. Multilevel modeling was used to determine associations between peak magnitudes of positive and negative vertical displacement of COM on pitch velocity and elbow valgus torque. Every fastball throughout the season with biomechanics data for each pitcher was included in the multilevel model. Results: Fastball velocity was mean ± SD 90.68 ± 2.90 mph (40.54 ± 1.29 m/s). Mean maximal negative vertical COM displacement was −0.91 ± 0.47 inches (−0.023 ± 0.012 m), which occurred 18.1% ± 5.75% of the way between peak knee height and stride foot contact. Mean maximal positive vertical COM displacement was 1.73 ± 1.14 inches (0.044 ± 0.029 m), which occurred 65.7% ± 7.8% of the time from peak knee height to stride foot contact. Positive COM displacement (β = 0.54; P < .001) and timing of peak positive COM displacement (β = 1.82; P = .023) reduced interpitcher variance by 9.9% and improved the ability of our model to predict fastball velocity. Negative COM displacement improved the ability of our model to predict ball velocity (β = −0.45; P = .021). Vertical COM displacement did not influence elbow valgus torque. Conclusion: Increasing vertical COM displacement in either the positive or the negative direction resulted in increased fastball velocity but did not result in greater elbow valgus torque. This indicates that the stride method may be used for performance enhancement but is unlikely to influence ulnar collateral ligament injury risk in college baseball pitchers. Clinical Relevance: Clinicians should not use stride mechanics as an injury risk indicator or diagnostic factor in injury etiology for college baseball pitchers.

Relationship of shoulder internal and external rotation peak force and rate of force development to throwing velocity in high school and collegiate pitchers

The purpose of this research was to characterize the difference between high school (HS) and collegiate pitcher’s throwing velocity, shoulder internal (IR) and external rotator (ER) maximum strength (Fmax) and rate of force development (RFD) and explore relationships between these measures. Competitive HS and collegiate pitchers (n = 26) participated in a single session assessment in which shoulder rotator isometric Fmax and RFD were quantified via a portable strain gauge device and throwing velocity via radar. Paired t-tests, stepwise linear regression models and correlational analyses were used to answer the questions of interest. No significant differences (p > 0.05) in pitching velocity were observed between HS and collegiate pitchers, and all pitchers were pooled into one sample for subsequent analyses. For both IR and ER models, the explained variance of Fmax with throwing velocity was small (R2 = 0.12–0.13). RFD and arm length did not contribute to the models. Large correlations (r ≥ 0.50; p < 0.001) were observed between IR and ER for Fmax and RFD measures, as well as between Fmax and RFD for IR and ER. In terms of throwing velocity, having strong IR and ER Fmax capabilities would seem more important than the ability to express force quickly in this cohort.

Kinematic Modeling of Pitch Velocity in High School and Professional Baseball Pitchers: Comparisons With the Literature.

Kinematic parameters predictive of pitch velocity have been evaluated in adolescent and collegiate baseball pitchers; however, they have not been established for high school or professional pitchers. To create multiregression models using anthropometric and kinematics features most predictive for pitch velocity in high school and professional pitchers and compare them with prior multiregression models evaluating other playing levels. Descriptive laboratory study. High school (n = 59) and professional (n = 337) baseball pitchers threw 8 to 12 fastballs while being evaluated with 3-dimensional motion capture (480 Hz). Using anthropometric and kinematic variables, multiregression models for pitch velocity were created for each group. A systematic review was conducted to determine previous studies that established kinematic models for ball velocity in youth, high school, and collegiate pitchers. Leg length was predictive of pitch velocity for high school and professional pitchers (P < .001 for both). When compared with previously established models for pitch velocity, almost all groups were distinct from one another when assessing age (P maximum < .001), weight (P max = .0095), and pitch velocity (P max < .001). Stride length was a significant predictor for the youth/high school pitchers, as well as the current study's high school and professional pitchers (P < .001 for all). Maximal shoulder external rotation (collegiate: P = .001; professional: P < .001) and maximal elbow extension velocity (high school/collegiate: P = .024; collegiate: P < .001; professional: P = .006) were shared predictors for the collegiate and current study's professional group multiregression models. Trunk flexion at ball release was a commonly shared predictor in the youth/high school (P = .04), high school/collegiate (P = .003), collegiate (P < .001), and the current study's professional group (P < .001). Youth, high school, collegiate, and professional pitchers had unique, predictive kinematic and anthropometric features predictive of pitch velocity. Leg length, stride length, trunk flexion at ball release, and maximal shoulder external rotation were predictive features that were shared between playing levels. Coaches, clinicians, scouts, and pitchers can consider both the unique and the shared predictive features at each playing level when attempting to maximize pitch velocity.

Poster 169: Preliminary Outcomes of Revision UCL Repair With Suture Tape Augmentation for Failure of Primary UCL Reconstruction in Professional and Collegiate Pitchers

Objectives: Injury of the ulnar collateral ligament (UCL) is common in baseball players and pitchers, in particular. The gold standard surgical treatment has been UCL reconstruction with autograft, although, UCL repair with collagen-coated suture tape has shown promise as an alternative recently. The outcomes of UCL reconstruction and UCL repair are well-studied, demonstrating high rates of return to sport and a predictable postoperative course of recovery. However, revision UCL reconstructions with allografts do not demonstrate comparable outcomes when compared with primary procedures. This pilot case series reports on the preliminary outcomes of collegiate and professional pitchers who underwent revision UCL repair with collagen-coated suture tape following failure of primary UCL reconstruction. Methods: We performed a retrospective query of a prospectively collected data repository to identify patients at our institution who had undergone UCL repair with internal brace. Additional inclusion criteria included: 1) prior failed UCL reconstruction with autograft; 2) aged between 15 and 45 years; 3) at least 1-year post-operative. From the included cohort, we collected demographic, clinical, and surgical data from the electronic health record. We further collected patient-reported outcomes data using either a web-based database platform or via telephone, including the American Shoulder and Elbow Surgeons Elbow assessment form (ASES-E; satisfaction, pain, and function subscales), the Kerlan Jobe Orthopaedic Clinic Shoulder and Elbow score (KJOC), Andrews Carson score, and information on return-to-sport timing and success. To evaluate outcomes, we reported the proportions of athletes that were able to successfully return-to-sport at the preinjury level or higher as well as return-to-sport timing and level of competition. Additionally, we reported summary statistics for patient-reported questionnaires evaluated at follow-up (ASES-E, KJOC, and Andrews Carson). Results: A total of 10 patients met inclusion criteria, and all were professional or collegiate pitchers at the time of their revision UCL repair surgery (40% professional and 60% collegiate). The mean follow-up time was 3.0 years (Table 1; range: 1-5 years). Table 1 shows complete return-to-sport data. All patients were able to return-to-sport at the same or higher level, and the mean time from surgery to return-to-sport was 9.3 months. Table 2 shows complete patient-reported outcomes data. Mean scores on elbow-related function questionnaires were high (ASES-E Function = 35.8 out of a maximum best of 36; KJOC = 88.3 out of a maximum best of 100; Andrews Carson = 94.5 out of a maximum best of 100) and mean pain scores were low (ASES-E Pain = 1 out of a maximum worst score of 50). Conclusions: This pilot case series demonstrated promising results of a novel UCL repair approach utilizing collagen-coated suture tape for high-level pitchers with recurrent medial elbow instability following initial UCL reconstruction with autograft. Specifically, we found excellent return-to-sport success and patient-reported outcomes in this preliminary cohort. Further study is warranted with larger sample sizes to further evaluate outcomes following revision of UCL reconstruction with UCL repair utilizing internal bracing.

Countermovement Jump and Momentum Generation Associations to Fastball Velocity Performance Among Division I Collegiate Pitchers.

Sakurai, M, Qiao, M, Szymanski, DJ, and Crotin, RL. Countermovement jump and momentum generation associations to fastball velocity performance among Division I collegiate pitchers. J Strength Cond Res 38(7): 1288-1294, 2024-The current study explored the relationships between countermovement jump (CMJ) profiles and baseball pitching performance. Nineteen Division I collegiate pitchers performed in-laboratory pitching and bilateral CMJs. Whole-body kinematics and ground reaction force were collected during both pitching and CMJ evaluations. Statistically significant correlations of concentric impulse and peak power in the CMJ test with fastball velocity were observed (r = 0.71 and 0.68). Concentric impulse in CMJ also showed a statistically significant correlation with linear momentum in the anterior-posterior direction during pitching (r = 0.68). Lean body mass and body mass showed statistically significant correlations with both of the 2 linear momentums during pitching (r = 0.71∼0.83), and concentric impulse in CMJ (r = 0.71 and 0.81). Pelvis and trunk pitching mechanics did not correlate with any of the CMJ variables at the statistically significant level, whereas the direction of the correlations varied (|r| < 0.45). Assessment of a baseball pitcher's CMJ should focus on concentric impulse and peak power because only these showed meaningful relationships with fastball velocity or momentum generation during pitching. An increase in lean body mass is also suggested to be able to generate more impulse and momentum. Baseball coaches, strength coaches, and clinicians are encouraged to include lower-body explosive training to enhance the force and power output capacity of baseball pitchers.

A Model for Causality of Pitching-related Overuse Injuries in Women's Fastpitch Softball.

Fastpitch softball is a popular women's sport, and athletes, particularly pitchers, are at high risk for overuse injury. Softball-related injury rates are low; however, the prevalence of overuse injuries is high. Injuries at the high school and collegiate levels occur early in the season, and approximately 50% of shoulder and elbow injuries in softball are attributable to overuse. Survey research showed 77% of high school pitchers pitch with pain, and 73% of collegiate pitchers reported an overuse injury in the previous season. Modifiable and non-modifiable intrinsic and extrinsic risk factors contribute to injury risk in a model that can be used in history taking, clinical examination, and management of softball-related injuries. In this manuscript, we present a scoping review of fastpitch softball injury research by competitive levels from 1990 to present. We also introduce a model for overuse injury causality in this athlete population. With this information, clinicians will be able to identify risk factors related to injury in softball pitchers. More research is needed to make evidence-based recommendations for injury prevention in this athlete population.

Comparison of glenohumeral and scapulothoracic kinematics between fastballs and curveballs during baseball pitching

ABSTRACT Shoulder injuries are common in baseball pitchers and primarily involve the glenohumeral joint. Past analyses have examined shoulder biomechanics during different pitch types simply as the motion of the upper arm relative to the thorax. In this study, glenohumeral and scapulothoracic kinematics were compared between fastballs and curveballs at key timepoints throughout a pitch. Upper extremity kinematics of thirteen collegiate pitchers were collected during fastball and curveball pitches with motion capture. A linear model approach was utilised to estimate scapular kinematics based on measurable humerothoracic motion. Glenohumeral kinematics were computed from the scapular and humeral motion data. Comparisons of scapulothoracic and glenohumeral kinematic variables at times of maximum glenohumeral external rotation, ball release, and maximum glenohumeral internal rotation between pitch types were made using paired t-tests with Benjamini-Hochberg corrections. There were no significant differences in glenohumeral kinematics. Fastballs elicited significantly less scapulothoracic internal rotation and more posterior tilt at maximum glenohumeral external rotation. Fastballs produced significantly less scapulothoracic internal rotation and anterior tilt at maximum glenohumeral internal rotation. This study provides further evidence that risk of injury to the glenohumeral joint may be consistent between fastballs and curveballs and offers insights into subtle differences in scapular kinematics between pitch types.

Exploratory Investigation Into the Impact of Bilateral and Unilateral Jump Characteristics on Ground Reaction Force Applications in Baseball Pitching.

Lis, R, Szymanski, DJ, Qiao, M, and Crotin, RL. An exploratory investigation into the impact of bilateral and unilateral jump characteristics on ground reaction force applications in baseball pitching. J Strength Cond Res XX(X): 000-000, 2022-Jump tests are effective, valid, and reliable in examining lower-body power that can influence ground reaction forces (GRFs) in baseball pitching. Relationships between drive and stride leg GRFs and fastball velocities while pitching from the wind-up and stretch were evaluated for performance influences across the following conditions: (a) lower-body GRFs from unilateral countermovement jumps (UCMJ) and bilateral countermovement jumps (BCMJ) and (b) BCMJ and drive and stride leg UCMJ height. Nineteen Division I collegiate baseball pitchers (age; 19.9 ± 1.5 years, height; 1.86 ± 0.06 m, body mass; 90.7 ± 13.8 kg) completed BCMJ and UCMJ tests and threw four-seam fastballs from a pitching mound with 2 embedded force plates. Three moderate associations (r ≥ 0.47) were statistically significant (p < 0.05) for BCMJ and UCMJ heights to pitching GRFs. Stride leg UCMJ height was significantly greater than drive leg UCMJ height, p < 0.01, η2 = 0.34. Wind-up and stretch GRFs were statistically similar. Fastball velocities showed a statistically significant association that was moderately high with wind-up and stretch stride leg anterior-posterior GRFs (r ≥ 0.65, p < 0.01). Collegiate pitchers jumped significantly higher with their stride leg, and the sum of vertical unilateral jump height of both legs was significantly greater (27%) than BCMJ height to indicate greater single-leg dominance in jumping. Although stride leg height was higher, improving stride leg jumping performance may be functionally more important in producing greater momentum into foot strike that has the potential to increase fastball velocity.

Bilateral Humeral Retrotorsion Angle Measured Using an Ultrasound-Assisted Technique in Asian Baseball Players.

Repetitive pitching is thought to restrict the physiological derotation process of the humeral head. Some studies have reported that side-to-side differences in the humeral retrotorsion angle (ΔHRA) occur between the ages of 9 and 11 years in baseball players. However, it remains unclear whether the ΔHRA in Asian baseball players depends on pitching skill or competitive level. To evaluate the ΔHRA in Asian collegiate and professional baseball players and to determine the effects of pitching activity on the physiological derotation process of the humeral head. Cross-sectional study; Level of evidence, 3. We evaluated 128 shoulders in 64 Asian baseball players who were stratified into 4 groups as follows: 13 professional pitchers; 9 professional fielders; 8 collegiate pitchers; and 34 collegiate fielders. The throwing and nonthrowing side HRA was assessed using an ultrasound-assisted technique, and the ΔHRA was compared among the 4 groups. In addition, Pearson correlation analysis was used to assess the relationship between ΔHRA and glenohumeral range of motion, baseball starting age, and fastball velocity in pitchers. The HRA was significantly greater in the throwing arm than in the nonthrowing arm in each group, with no significant differences among the groups. There was no correlation between ΔHRA and range of motion or fastball velocity. There was a significant negative correlation between baseball starting age and ΔHRA in professional fielders (r = -0.633; P = .036). The findings of the present study provide evidence that in Asian baseball players, the HRA was significantly greater in the throwing arm than in the nonthrowing arm. There were no clear associations between HRA and pitching ability or competitive level.

Collegiate baseball pitchers demonstrate a relationship between ball velocity and elbow varus torque, both within and across pitchers

ABSTRACT High elbow varus torque during baseball pitching has been identified as a potential cause of ulnar collateral ligament injury in baseball pitchers. In general, elbow varus torque increases as ball velocity increases across pitchers. However, studies incorporating within-subject analyses report that not all professional pitchers have a positive relationship between elbow varus torque and ball velocity (T-V relationship). It remains unknown whether collegiate pitchers show the same trend as professionals in their T-V relationships. The current study investigated the T-V relationship of collegiate pitchers focusing on both across and within pitchers. Division 1 collegiate pitchers (n = 81) were assessed for elbow torque and ball velocity during pitching. Both across- and within-pitcher T-V relationships were significant (p < 0.05) using linear regression. However, more variance in elbow varus torque was explained using the within-pitcher relationship (R2 = 0.29) than the across-pitcher relationship (R2 = 0.05). Of the 81 pitchers, nearly half (n = 39) had significant T-V relationships, while the other half (n = 42) did not. Our findings indicate that the T-V relationship should be assessed on an individual basis as T-V is pitcher-specific.

Pitching mechanics and performance of adult baseball pitchers: A systematic review and meta-analysis for normative data.

The aim of this systematic review was to critically review and synthesise the findings from primary studies on pitching mechanics and performance of healthy adult baseball pitchers. Systematic review with meta-analysis. Eight English- and Japanese-language databases were systematically searched from inception to 22nd July 2022. In total, 29 descriptive biomechanical studies were included. Overall study quality was moderate. In subgroup analyses, professional pitchers showed significantly higher stride length, peak shoulder internal rotation velocity, peak shoulder proximal force and ball velocity compared to collegiate pitchers. Conversely, collegiate pitchers were found to have significantly higher peak pelvis rotation velocity. Available normative data suggested potentially heterogeneous pitching mechanics and performance between professional and collegiate pitchers. However, the findings in this review should be interpreted cautiously. Since statistical heterogeneity was significant within most data sets, more detailed subgroup analyses are required. Additionally, more high-quality studies utilising measurement systems with established reliability are required to obtain accurate data in baseball pitching mechanics and performance.

Sensor Location Matters When Estimating Player Workload for Baseball Pitching.

Estimating external workload in baseball pitchers is important for training and rehabilitation. Since current methods of estimating workload through pitch counts and rest days have only been marginally successful, clubs are looking for more sophisticated methods to quantify the mechanical loads experienced by pitchers. Among these are the use of wearable systems. While wearables offer a promising solution, there remains a lack of standards or guidelines for how best to employ these devices. As a result, sensor location and workload calculation methods vary from system to system. This can influence workload estimates and blur their interpretation and utility when making decisions about training or returning to sport. The primary purpose of this study was to determine the extent to which sensor location influences workload estimate. A secondary purpose was to compare estimates using different workload calculations. Acceleration data from three sensor locations-trunk, throwing upper arm, and throwing forearm-were collected from ten collegiate pitchers as they threw a series of pitches during a single bullpen session. The effect of sensor location and pitch type was assessed in relation to four different workload estimates. Sensor location significantly influenced workload estimates. Workload estimates calculated from the forearm sensor were significantly different across pitch types. Whole-body workload measured from a trunk-mounted sensor may not adequately reflect the mechanical loads experienced at throwing arm segments. A sensor on the forearm was the most sensitive to differences in workloads across pitch types, regardless of the calculation method.

Clinical shoulder measurements related to joint loads in collegiate pitchers

Pitchers are prone to upper extremity injury due to repetitive high joint loads. Clinical measures of shoulder strength and range of motion (ROM) have shown links to injury risk in pitchers, however, these factors have rarely been studied in relation to throwing joint loads. The purpose of this study was to identify which clinical ROM and isokinetic strength variables were related to peak shoulder and elbow joint torques in collegiate pitchers. Thirty-three healthy collegiate pitchers participated in this study. Fastball velocity, shoulder concentric and eccentric strength, and passive shoulder ROM variables were analyzed using a Lasso regression to determine what factors influenced shoulder internal rotation torque and elbow varus torque. Fastball velocity was selected by the Lasso as indicator of increased shoulder and elbow torque. Passive shoulder external rotation ROM was also selected as an important factor in joint loading with increased shoulder external rotation ROM being related to lower joint loads. The bilateral ratio of shoulder internal rotator concentric strength was related to peak shoulder and elbow torques with an increase in the bilateral ratio of shoulder strength leading to reduced joint torques. Increases in the eccentric external rotator to concentric internal rotator strength (functional ratio) of the dominant arm and increases in dominant arm eccentric internal rotator strength were both related to increases in each joint torque. Results from the study indicate that pitch speed, passive shoulder external rotation ROM, and the isokinetic shoulder strength profile including internal rotator strength and functional strength ratio of pitchers are related to joint loading during the pitch and may be important to monitor in relation to injury risk and/or during rehabilitation. These results provide insight into the role that both shoulder ROM and rotator cuff strength play in the dynamic stabilization of the elbow and shoulder during pitching.

Determinants of Biomechanical Efficiency in Collegiate and Professional Baseball Pitchers

Background: Biomechanical efficiency, defined as fastball velocity per unit of normalized elbow varus torque, is a relatively new metric applied to improving the performance and health of baseball pitching. Purpose/Hypothesis: The purpose of this work was to evaluate kinematic parameters influencing biomechanical efficiency among professional and collegiate pitchers. Kinematic differences were compared between pitchers of high and low biomechanical efficiency. We hypothesized that professional pitchers would have greater biomechanical efficiency than collegiate pitchers. Study Design: Descriptive laboratory study. Methods: A deidentified biomechanical database of 545 pitchers (447 professional, 98 collegiate) was analyzed. A multivariate linear regression model was used to evaluate significant findings a priori with α = .05. Additionally, biomechanical differences were identified between competition levels and between high and low biomechanical efficiency groups using Mann-Whitney U test (α = .05). Results: Competition level and 11 (of 21) kinematic variables explained 27% of the variance in biomechanical efficiency, with most of the predictors being throwing arm kinematics (elbow flexion at stride foot contact [SFC]: β, −1.47; SE, 0.26; shoulder abduction at SFC: β, −1.78; SE, 0.39; shoulder external rotation at SFC: β, 0.60; SE, 0.22; maximum external rotation [MER] angle: β, 1.82; SE, 0.42; shoulder horizontal adduction at MER: β, −3.42; SE, 0.71) (all P≤ .05). Professional pitchers had greater biomechanical efficiency than collegiate pitchers (711.0 ± 101.0 vs 657.0 ± 99.3, respectively; P < .001; d = 0.53). Compared with the low-efficiency group, the high-efficiency group had significantly lower normalized elbow varus torque with greater weight and height (high: 0.047 ± 0.004 %wt*ht vs. low: 0.063 ± 0.006 %wt*ht, P <.001; d = 3.20). At the instant of SFC, the high-efficiency group demonstrated greater shoulder external rotation and less elbow flexion, shoulder abduction, and pelvic rotation. The high-efficiency group also had greater MER and less shoulder horizontal adduction at MER, trunk side tilt at ball release, and knee excursion from foot contact to ball release. Conclusion: Professional pitchers had greater biomechanical efficiency than collegiate pitchers. Biomechanical efficiency was also affected by 11 kinematic variables identified in this study. Pitchers with higher efficiency had distinct differences in arm position, trunk side tilt, and lead-knee extension range of motion in the delivery. Thus, pitchers and baseball organizations should focus on these factors to lower normalized elbow varus torque relative to ball velocity.

Evaluation of approaches to estimate scapular kinematics during baseball pitching

ABSTRACT Biomechanical analyses of pitching possess limitations in accurately measuring dynamic scapular orientation and are thus unable to distinguish between glenohumeral and scapulothoracic contributions to global shoulder motion. In lieu of direct measurement, several methods to estimate scapular kinematics have been developed. This study evaluated the ability of the linear model and the double calibration acromion marker cluster (D-AMC) approaches to estimate scapular kinematics throughout a full-speed pitching motion. Each approach’s estimates were compared against scapulothoracic range of motion limits established in a non-pitching biplane fluoroscopy study involving various functional arm movements that approximate physiological limits of scapular motion. Fourteen healthy collegiate pitchers participated. Motion capture measured upper extremity joint kinematics during full-speed fastball pitches. Linear model and D-AMC approaches estimated scapulothoracic kinematics during each pitch. Linear model estimates of scapulothoracic kinematics were largely within established physiological limits on each scapular axis of motion while D-AMC estimates exceeded fluoroscopy-established bounds for more subjects and by larger, less physiologically plausible amounts. These findings demonstrate that the linear model outperforms the D-AMC and suggest that it is a viable approach to estimate scapular kinematics during pitching. Finally, these results offer additional evidence to support the accepted pattern of scapular kinematics during pitching.

Efficacy Of Proteus Motion Training To Increase Fastball Velocity In Collegiate Pitchers

Efficacy Of Proteus Motion Training To Increase Fastball Velocity In Collegiate Pitchers

Pelvis and Trunk Energy Flow in Collegiate Softball Pitchers With and Without Upper Extremity Pain

Background: The softball pitch is a full-body motion, where efficient proximal to distal energy flow through the kinetic chain is said to reduce stress at the upper extremity. Although altered trunk kinematic parameters are associated with upper extremity pain in softball pitchers, further research is needed to determine whether differences exist in proximal energy flow between softball pitchers with and without pain. Hypothesis/Purpose: To examine pelvis and trunk energy flow during the acceleration phase of the pitch in collegiate softball pitchers with and without upper extremity pain. It was hypothesized that those with upper extremity pain would have less energy flowing into the proximal ends of the pelvis and trunk as well as less energy flowing out of the distal ends of the pelvis and trunk during the acceleration phase when compared with pitchers who did not have upper extremity pain. Study Design: Descriptive laboratory study. Methods: A total of 54 female National Collegiate Athletic Association Division I softball pitchers (age, 20.2 ± 2.0 years; height, 173.5 ± 6.9 cm; weight, 78.5 ± 11.5 kg) were assigned to pain (n = 17) and pain-free (n = 38) groups. Participants pitched 3 maximal effort rise-balls for a strike, and the average of the 3 trials was used for analysis. Kinematic data were collected at 100 Hz using an electromagnetic tracking system. A segment power analysis was performed to quantify energy flow for the pelvis and trunk. The Mann-Whitney U test was used to compare pelvis and trunk energy flow during the acceleration phase of the pitch as well as pitch velocity between collegiate softball pitchers with and without upper extremity pain. Results: No significant differences were found between pelvis and trunk energy flow during the acceleration phase or pitch velocity between collegiate softball pitchers with and without upper extremity pain (all P values >.057). Conclusion: Previous research determined that kinematic parameters differ between collegiate pitchers with and without upper extremity pain. However, the current study found no difference in pelvis and trunk energy flow or pitch velocity. Although altered kinematics in collegiate pitchers with upper extremity pain may serve as compensation patterns to maintain pitch velocity and proximal energy flow, future research is needed to confirm this postulation. Clinical Relevance: The lack of energy flow differences between upper extremity pain groups suggests that pitchers may adapt their biomechanics to maintain trunk and pelvis energy flow patterns. Coaches, athletes, and clinicians should know that movement adaptations can allow for maintained performance levels but may result in the presence of pain that may manifest in other deleterious and injury-susceptible biomechanics.

Sonographic morphological and qualitative deficits in the elbow ulnar collateral ligament and ulnohumeral joint in throwing arms of asymptomatic collegiate baseball pitchers.

The ulnar collateral ligament (UCL) supports the medial elbow against valgus torque and is commonly injured in baseball pitchers. Changes in UCL morphology and pathology occur with long-term pitching, with more severe findings at higher competition levels. We examined the bilateral differences and the relationship between UCL morphology, pathology, and ulnohumeral joint laxity in asymptomatic collegiate pitchers using ultrasound. Division I college pitchers (n = 41) underwent ultrasound scans of their bilateral medial elbows, both at rest and in a valgus-stressed position. The presence of enthesopathy, calcifications, and degeneration was assessed qualitatively. UCL thickness and ulnohumeral joint gap were measured with online calipers. The bilateral differences were analyzed using paired t-tests and chi-square analysis, and the relationships between thickness, gapping, and degenerative changes were analyzed using regression analyses. The throwing arm demonstrated greater distal UCL thickness (mean difference (MD) = 0.2mm (95%CI = 0.1-0.3), p < 0.01), resting and stressed gap (MD = 0.3mm (95%CI = 0.0-0.7), p = 0.04; MD = 0.4 (95%CI = 0.0-0.9), p = 0.02), and greater prevalence of degeneration and enthesopathy (p = 0.03) compared bilaterally. Enthesopathy and calcifications predicted increased distal UCL thickness (p = 0.04; p = 0.02). Degenerative scores predicted increased stressed-resting ulnohumeral joint gap (p < 0.01). In the throwing arms of collegiate pitchers, ultrasound demonstrated UCL thickening, enthesopathy/intra-ligamentous calcification, and greater laxity of the ulnohumeral joint relative to the non-throwing arm. Degeneration of the UCL, not thickness, was related to greater elbow joint gapping. This study demonstrates the utility of ultrasound for examining sonographic characteristics of the UCL in a sample of college pitchers.