Pitching Mechanics and the Relationship to Accuracy in Professional Baseball Pitchers

Background: Biomechanical predictors of pitching accuracy are underevaluated in baseball research. It is unclear how pitchers with higher accuracy differ in terms of kinematics and upper extremity kinetics. Purpose: To differentiate high- and low-accuracy professional pitchers by full-body kinematic and upper extremity kinetic parameters. Study Design: Descriptive laboratory study. Methods: In total, 121 professional baseball pitchers threw 8 to 12 fastballs while assessed with motion-capture technology (480 Hz). Pitchers were divided into high-accuracy (n = 33), moderate-accuracy (n = 52), and low-accuracy (n = 36) groups based on the absolute center deviation of each pitcher’s average pitch to the center of the pitching chart by greater or less than 0.5 SD from the mean, respectively. The 95% confidence ellipses with comparisons of major and minor radii and pitching probability density grids were constructed. Analysis of variance was used to compare kinematic and kinetic values between groups. Results: The absolute center deviation (14.5% ± 6.7% vs 33.5% ± 3.7% grid width; P < .001) was significantly lower in the high-accuracy compared with the low-accuracy group, with no significant difference in ball velocity (38.0 ± 1.7 vs 38.5 ± 2.0 m/s; P = .222). Lead knee flexion at ball release (30.6°± 17.8° vs 40.1°± 16.3°; P = .023) was significantly less for the high-accuracy pitchers. Peak normalized shoulder internal rotation torque (5.5% ± 1.0% vs 4.9% ± 0.7% body weight [BW] × body height [BH]; P = .008), normalized elbow varus torque (5.4% ± 1.0% vs 4.8% ± 0.7% BW × BH; P = .008), and normalized elbow medial force (42.9% ± 7.3% vs 38.6% ± 6.2% BW; P = .024) were significantly greater for the low-accuracy group compared with the high-accuracy group. Conclusion: Professional pitchers with increased accuracy experienced decreased throwing arm kinetics. These pitchers had increased lead knee extension at later stages of the pitch, potentially providing more stable engagement with the ground and transference of kinetic energy to the upper extremities. Professional pitchers can consider increasing lead knee extension at the final stages of the pitch to improve the accuracy of their throws and mitigate elbow varus torque. Clinical Relevance: Increased elbow varus torque, shoulder internal rotation torque, and elbow medial force in less accurate pitchers may contribute to increased injury risk in this group.

Cryoneurolysis for Digital Neuralgia in Professional Baseball Players: A Case Series

ObjectiveWe describe a non-surgical approach to refractory digital neuralgia using cryoneurolysis in a series of 3 professional baseball players.BackgroundThumb injuries are common in baseball players and can sometimes be challenging to effectively manage. Depending on the injury, current treatments include anti-inflammatories, immobilization, physical therapy, corticosteroid injections, and/or surgery. A subset of patients, however, fail nonoperative management yet do not have a clear indication for surgery. Cryoneurolysis or cyroanalgesia is an FDA-approved form of neuromodulation, which has been used safely and effectively on a variety of peripheral nerves. The mechanism of action involves percutaneous introduction of a small probe under local anesthetic to nerve tissue using ultrasound guidance. The probe is then cooled to −88°C using nitrous oxide, which results in secondary Wallerian degeneration. Axonal and myelin regeneration occurs completely in 3–6 months.Design/MethodsVisualization of the superficial radial sensory and ulnar digital nerve were obtained under ultrasound. The skin was prepared in sterile fashion. A 22-gauge 1-½ inch needle was then advanced with ultrasound guidance, and local anesthetic was applied. Both treatment sites were marked with skin marker. Cryoneurolysis was employed using a 5 mm tip. 60-second treatment cycles were performed at each site. Each of the cycles resulted in a 5 × 7 mm lesion visible as hypoechoic signal.ResultsAll 3 players endorsed significant and prolonged relief and were able to return to an elite level of play.ConclusionsThis manuscript is subject to all of the limitations of a case series, and larger rigorous studies are needed to illuminate causal inferences. Novel, complex technologies may also be more susceptible to placebo effect. Nonetheless, we are able to report marked efficacy and safety from cryoneurolysis of the ulnar digital nerve and the superficial radial sensory nerve in a small group of elite baseball players with refractory digital neuralgia.

Are Baseball Statistics an Appropriate Tool for Assessing Return to Play in Injured Pitchers? Analysis of Statistical Variability in Healthy Players

Background: Basic pitcher statistics have been used to assess performance in pitchers after injury or surgery without being validated. Even among healthy pitchers, the normal variability of these parameters has not yet been established. Purpose: To determine (1) the normal variability of basic and advanced pitcher statistics in healthy professional baseball pitchers and (2) the minimum pitches needed to predict these parameters. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Publicly available data from the MLB Statcast and PITCHf/x databases were used to analyze MLB pitchers during the 2015 and 2016 seasons who recorded a minimum of 100 innings without injury. Basic and advanced baseball pitcher statistics were analyzed. The variability of each parameter was assessed by computing the coefficient of variation (CV) between individual pitchers and across all pitchers. A CV <10 was indicative of a relatively constant parameter, and parameters with a CV >10 were generally considered inconsistent and unreliable. The minimum number of pitches needed to be followed for each variable was also analyzed. Results: A total of 118 pitchers, 55 baseball-specific statistical metrics (38 basic and 17 advanced), and 7.5 million pitches were included and analyzed. Of the 38 basic pitcher statistics, only fastball velocity demonstrated a CV <10 (CV = 1.5), while 6 of 17 (35%) advanced metrics demonstrated acceptable consistency (CV <10). Release position from plate and velocity from the plate were the 2 most consistent advanced parameters. When separated by pitch type, these 2 parameters were the most constant (lowest CV) across every pitch type. Conclusion: We recommend against utilizing nonvalidated statistical measures to assess performance after injury, as they demonstrated unacceptably high variability even among healthy, noninjured professional baseball pitchers. It is our hope that this study will serve as the foundation for the identification and implementation of validated pitcher-dependent statistical measures that can be used to assess return-to-play performance after injury in the future.

Progressive enlargement of thoracic ossification of the ligamentum flavum in professional baseball pitchers: a report of two cases

Both systemic and local factors might influence the development of ossification of the ligamentum flavum (OLF); however, whether specific physical activities play a role in the development of OLF remains unclear. This report presents two cases of thoracic radiculopathy owing to progressive enlargement of thoracic OLF within a few years in Japanese professional baseball pitchers. Two left-handed, Japanese, professional baseball pitchers in their 20s experienced thoracic radiating pain. Mild hypesthesia of the lower thoracic vertebral levels was observed, and an increase in the size of the OLF within a few years was identified in the lower thoracic spine using computed tomography and magnetic resonance imaging. Neither patient exhibited myelopathy and were, therefore, treated conservatively. Both patients were able to return to playing in top condition within 4 months after onset. The findings in these cases suggest that thoracic OLF might increase in size and become exacerbated in certain individuals, such as professional pitchers, who experience repeated, localized, mechanical stress on the thoracic spine, irrespective of age.