Overuse injuries in youth baseball players due to throwing are at an all-time high. Traditional methods of tracking player throwing load only count in-game pitches and therefore leave many throws unaccounted for. Miniature wearable inertial sensors can be used to capture motion data outside of the lab in a field setting. The objective of this study was to develop a protocol and algorithms to detect throws and classify throw intensity in youth baseball athletes using a single, upper arm-mounted inertial sensor. Eleven participants from a youth baseball team were recruited to participate in the study. Each participant was given an inertial measurement unit and was instructed to wear the sensor during any baseball activity for the duration of a summer season of baseball. A throw identification algorithm was developed using data from a controlled data collection trial. In this report, we present the throw identification algorithm used to identify over 17,000 throws during the 2-month duration of the study. Data from a second controlled experiment was used to build a support vector machine model to classify throw intensity. Using this classification algorithm, throws from all participants were classified as being "low," "medium," or "high" intensity. The results demonstrate that there is value in using sensors to count every throw an athlete makes when assessing throwing load, not just in-game pitches.

Purpose: To systematically review the available literature to further describe and report the available data on SLAP repair techniques and the association with outcomes. Methods: A systematic review of literature was performed on manuscripts describing type II SLAP repairs in athletes. Selection criteria included studies reporting exclusively type II SLAP tears without concomitant pathology, minimum 2-year postoperative follow-up, use of anchor fixation, and return to previous level of play data available. We extracted patient outcome as well as surgical construct details from each article. Average outcomes and return to play rates were calculated and substratified further by athlete type. Return to play rates were compared by repair constructs with the Student t test. Results: Initial search resulted in 107 articles. After exclusion criteria were applied, 17 articles were included in the final analysis. Overall, 84% of patients had good-to-excellent results. Of all athletes, 66% returned to previous level of play. There was significant variation in reported technique in terms of anchor number, location, material, suture type, and knotless versus knotted constructs. No significant difference was reported in outcomes in comparison of suture type (P-value .96) or knotted versus knotless constructs (P-value .91). Given the significant variability in reporting, no statistical analysis was felt able to be performed on anchor location and number. Conclusions: Repair of type II SLAP tears in athletes is a difficult problem to treat with overall low return to play despite a high rate of "good" outcomes when assessed by outcome measures. Significant variability exists in surgical technique, as well as reporting of surgical technique, potentially limiting the ability to define the best or most effective technique for SLAP repair. Level of Evidence: IV, systematic review of level III and level IV studies.

Background: Pitch count recommendations are used to reduce injury risk in youth baseball pitchers and are based chiefly on expert opinion, with limited scientific support. Furthermore, they only account for pitches thrown against a hitter and do not include the total number of throws on the day a player pitched. Currently, counts are recorded manually. Purpose: To provide a method using a wearable sensor to quantify total throws per game that is compliant with Little League Baseball rules and regulations. Study Design: Descriptive laboratory study. Methods: Eleven male baseball players (age, 10-11 years) from an 11U (players 11 years and younger) competitive travel team were evaluated over a single summer season. An inertial sensor was placed above the midhumerus of the throwing arm and was worn during baseball games across the season. A throw identification algorithm capturing all throws and reporting linear acceleration and peak linear acceleration was used to quantify throwing intensity. Pitching charts were collected and used to verify actual pitches thrown against a hitter in a game versus all other throws identified. Results: A total of 2748 pitches and 13,429 throws were captured. On the day a player pitched, he averaged 36 ± 18 pitches (23%) and 158 ± 106 total throws (pitches in game as well as all warm-up pitches and other throws during game). In comparison, on a day a player did not pitch, he averaged 119 ± 102 throws. Across all pitchers, 32% of all throws were low intensity, 54% were medium intensity, and 15% were high intensity. The player with one of the highest percentages of high-intensity throws did not pitch as their primary position, while the 2 players who pitched most often had the lowest percentages. Conclusion: Total throw count can be successfully quantified using a single inertial sensor. Total throws tended to be higher on days a player pitched compared with regular game days without pitching. Clinical Relevance: This study provides a fast, feasible, and reliable method to obtain pitch and throw counts so that more rigorous research on contributing factors to arm injury in the youth athlete can be achieved.