Background: Although lower extremity biomechanics has been correlated with traditional metrics among baseball players, its association with advanced statistical metrics has not been evaluated. Purpose: To establish normative biomechanical parameters during the countermovement jump (CMJ) among Major League Baseball (MLB) players and evaluate the relationship between CMJ-developed algorithms and advanced statistical metrics. Study Design: Cohort study; Level of evidence, 3. Methods: MLB players in 2 professional organizations performed the CMJ at the beginning of each baseball season from 2013 to 2017. We collected ground-reaction force data including the eccentric rate of force development (“load”), concentric vertical force (“explode”), and concentric vertical impulse (“drive”) as well as the Sparta Score. The advanced statistical metrics from each baseball season (eg, fielding independent pitching [FIP], weighted stolen base runs [wSB], and weighted on-base average) were also gathered for the study participants. The minimal detectable change (MDC) was calculated for each CMJ variable to establish normative parameters. Pearson coefficient analysis and regression trees were used to evaluate associations between CMJ data and advanced statistical metrics for the players. Results: A total of 151 pitchers and 138 batters were included in the final analysis. The MDC for “load,” “explode,” “drive,” and the Sparta Score was 10.3, 8.1, 8.7, and 4.6, respectively, and all demonstrated good reliability (intraclass correlation coefficient > 0.75). There was a weak but statistically significant correlation between the Sparta Score and wSB ( r = 0.23; P = .007); however, there were no significant correlations with any other advanced metrics. Regression trees demonstrated superior FIP with higher Sparta Scores in older pitchers compared with younger pitchers. Conclusion: There was a positive but weak correlation between the Sparta Score and base-stealing performance among professional baseball players. Additionally, older pitchers with a higher Sparta Score had statistically superior FIP compared with younger pitchers with a similar Sparta Score after adjusting for age.

Magnetic Resonance Imaging (MRI) and Ultrasound (US) imaging are both routinely used in the assessment of rotator cuff pathology. Factors influencing the frequency of use of the respective technologies include access to equipment, provider preference, and cost. The purpose of our study was to compare the accuracy of in clinic ultrasound with that of MRI in diagnosing pathology of the rotator cuff in a large sample size with limited exclusionary criteria. 500 patient profiles assessed by each imaging type, MRI and ultrasound, who then proceeded to arthroscopic surgery were gathered and analyzed for interobserver agreement between the image interpretation and the surgical observations. While ultrasound displayed slightly higher sensitivity and specificity ratings in the diagnosis of full tears (0.90 and 0.92 vs. 0.86 and 0.91), MRI had a higher sensitivity (0.87 vs. 0.80) and Ultrasound had a higher specificity (0.86 vs. 0.76) for general cuff damage. The Weighted Kappa Values for both MRI (0.699) and Ultrasound (0.668) both indicate a substantial strength of agreement between the image interpretation and surgical findings. While there was a balanced distribution of errors observed in the MRI category, the most common error made in the Ultrasound assessment was a false negative assessment of a partial tear. The data indicate that in a clinical setting Ultrasound imaging is a cost-effective and accurate alternative to MRI and can be a valuable addition to the diagnostic assessment of rotator cuff injury and pathology.

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Intra-articular glenohumeral joint injections are commonly performed in the clinical setting for diagnostic and therapeutic purposes. Multiple approaches are described, including the anterior and posterior approaches and the less studied superomedial (Neviaser) approach. The purpose of this study was to determine the length of needle required to enter the shoulder joint via the Neviaser approach by radiography and magnetic resonance imaging (MRI) measurements. Additionally, the authors sought to identify any correlation between needle length and body mass index (BMI). They performed a retrospective review of 101 consecutive patients evaluated by one faculty member at their institution. Inclusion criteria were age older than 50 years, no previous shoulder surgery, no history of acromioclavicular joint injury, and having a true anteroposterior radiograph and MRI within 1 year of each other. Using a digital imaging system, the Neviaser approach needle path was drawn for both images, and the lengths were measured. Correlation coefficients for needle length and BMI were calculated. The images of 58 (57.4%) male patients and 43 (42.6%) female patients were evaluated (average BMI, 31.2 kg/m 2 ). The average needle length measurement was 4.27 cm on radiograph and 3.9 cm on MRI. Correlation coefficients were r =0.36 ( P =.0002) using radiographs and r =0.53 ( P <.0001) using MRIs. When using the Neviaser approach, there is a moderate positive correlation between BMI and the measured distance between skin and the glenohumeral joint when assessed on MRI, and a weak positive correlation on radiographs. The authors conclude that an injection needle of 2 inches or greater is required to reliably access the shoulder joint, and this length may increase with increasing BMI. [ Orthopedics . 2020;43(4):e215–e218.]