Background: Fastpitch softball is a popular sport for young females. However, data are limited describing youth pitching mechanics. Normative data describing pitching mechanics in the two youngest player pitch leagues are critical to gaining an improved understanding of proper mechanics in an attempt to establish injury prevention programs. Purpose: The purpose of this study was to examine pitching mechanics in Little League softball pitchers and examine the relationship of these mechanics and participant anthropometrics to ball velocity.

The aims of the present study were to examine quantitatively ground reaction forces, kinematics, and muscle activations during the windmill softball pitch, and to determine relationships between knee valgus and muscle activations, ball velocity and muscle activation as well as ball velocity and ground reaction forces. It was hypothesized that there would be an inverse relationship between degree of knee valgus and muscle activation, a direct relationship between ground reaction forces and ball velocity, and non-stride leg muscle activations and ball velocity. Ten female windmill softball pitchers (age 17.6 ± 3.47 years, stature 1.67 ± 0.07 m, weight 67.4 ± 12.2 kg) participated. Dependent variables were ball velocity, surface electromyographic (sEMG), kinematic, and kinetic data while the participant was the independent variable. Stride foot contact reported peak vertical forces of 179% body weight. There were positive relationships between ball velocity and ground reaction force (r = 0.758, n = 10, P = 0.029) as well as ball velocity and non-stride leg gluteus maximus (r = 0.851, n = 10, P = 0.007) and medius (r = 0.760, n = 10, P = 0.029) muscle activity, while there was no notable relationship between knee valgus and muscle activation. As the windmill softball pitcher increased ball velocity, her vertical ground reaction forces also increased. Proper conditioning of the lumbopelvic-hip complex, including the gluteals, is essential for injury prevention. From the data presented, it is evident that bilateral strength and conditioning of the gluteal muscle group is salient in the windmill softball pitch as an attempt to decrease incidence of injury.

ObjectiveTo characterise whether preseason screening of shoulder range of motion (ROM) is associated with the risk of shoulder and elbow injuries in overhead athletes.DesignSystematic review and meta-analysis.Data sourcesSix electronic databases up to 22 September 2018.Eligibility criteriaInclusion criteria were (1) overhead athletes from Olympic or college sports, (2) preseason measures of shoulder ROM, (3) tracked in-season injuries at the shoulder and elbow, and (4) prospective cohort design. Exclusion criteria were (1) included contact injuries, (2) lower extremity, spine and hand injuries, and (3) full report not published in English.ResultsFifteen studies were identified, and they included 3314 overhead athletes (baseball (74.6%), softball (3.1%), handball (16.1%), tennis (2.0%), volleyball (2.0%) and swimming (2.2%)). Female athletes are unrepresented (12% of the overall sample). Study quality ranged from 11 to 18 points on a modified Downs and Black checklist (maximum score 21, better quality). In one study, swimmers with low (<93°) or high (>100°) shoulder external rotation were at higher risk of injuries. Using data pooled from three studies of professional baseball pitchers, we showed in the meta-analysis that shoulder external rotation insufficiency (throwing arm <5° greater than the non-throwing arm) was associated with injury (odds ratio=1.90, 95% confidence interval 1.24 to 2.92, p<0.01).ConclusionPreseason screening of shoulder external rotation ROM may identify professional baseball pitchers and swimmers at risk of injury. Shoulder ROM screening may not be effective to identify handball, softball, volleyball and tennis players at risk of injuries. The results of this systematic review and meta-analysis should be interpreted with caution due to the limited number of studies and their high degree of heterogeneity.PROSPERO registration numberCRD42017072895.

Background: Injury prevalence has been well described among baseball athletes; similarly, a better understanding of injuries in softball athletes is needed. Purpose: To examine shoulder and elbow injury epidemiology among high school softball athletes in the United States. Study Design: Descriptive epidemiological study. Methods: Injury data were obtained from the National High School Sports-Related Injury Surveillance System, which captures data from a large national sample of US high schools. Annually, a random sample of 100 high schools provided a representative sample with respect to the 4 US Census geographic regions and 2 school sizes (cutoff point, 1000 students). Athletic trainers from participating schools reported data for athlete-exposures (AEs; practice or competition) and shoulder and elbow injuries from 2005-2006 through 2016-2017. Results: A total of 239 shoulder injuries and 85 elbow injuries occurred within 2,095,329 AEs. The overall shoulder injury rate was 1.14 per 10,000 AEs, whereas the overall elbow injury rate was 0.41 per 10,000 AEs. Injuries to the shoulder were more likely to occur during competition as compared with practice (rate ratio, 1.28; 95% CI, 0.99-1.65). Half of the shoulder (50.4%) and elbow 48.9% injuries were due to an overuse/chronic mechanism. Of the athletes sustaining an injury, 86.8% with shoulder injuries and 93.0% with elbow injuries returned to play within 21 days. Only 16.7% of shoulder injuries and 17.5% of elbow injuries were sustained by pitchers. Conclusion: Shoulder and elbow injury rates, time to return, and percentage of injuries among pitchers were far lower in high school softball than previously reported values for high school baseball. There were relatively low incidences of shoulder and elbow injuries in high school softball as compared with baseball, with few injuries requiring lengthy time to return to play.

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Fast-pitch softball has become an increasingly popular sport for female athletes. There has been little research examining the windmill softball pitch in the literature. The purpose of this study was to describe the muscle activation patterns of 3 upper extremity muscles (biceps, triceps, and rhomboids [scapular stabilizers]) and 2 lower extremity muscles (gluteus maximus and medius) during the 5 phases of the windmill softball pitch. Data describing muscle activation were collected on 7 postpubescent softball pitchers (age 17.7 ± 2.6 years; height 169 ± 5.4 cm; mass 69.1 ± 5.4 kg). Surface electromyographic data were collected using a Myopac Jr 10-channel amplifier (RUN Technologies Scientific Systems, Laguna Hills, CA, USA) synchronized with The MotionMonitor™ motion capture system (Innovative Sports Training Inc, Chicago IL, USA) and presented as a percent of maximum voluntary isometric contraction. Gluteus maximus activity reached (196.3% maximum voluntary isometric contraction [MVIC]), whereas gluteus medius activity was consistent during the single leg support of phase 3 (101.2% MVIC). Biceps brachii activity was greatest during phase 4 of the pitching motion. Triceps brachii activation was consistently >150% MVIC throughout the entire pitching motion, whereas the scapular stabilizers were most active during phase 2 (170.1% MVIC). The results of this study indicate the extent to which muscles are activated during the windmill softball pitch, and this knowledge can lead to the development of proper preventative and rehabilitative muscle strengthening programs. In addition, clinicians will be able to incorporate strengthening exercises that mimic the timing of maximal muscle activation most used during the windmill pitching phases.

Strength deficits in the quadriceps and hamstrings have been linked to several lower extremity injuries. The most common protocol used in testing for these deficits is isokinetic strength testing, which is both costly and time consuming. Therefore, the purpose of this study was to employ common vertical and horizontal power field tests to identify those protocols that best predict lower extremity strength deficits. Data describing 22 healthy collegiate graduate students' vertical and horizontal power were collected using standard field tests (i.e., 2 feet vertical jump, single leg vertical jump, 40-, 50-, and 60-yd runs). In addition, data describing each subject's lower extremity strength deficits were collected by using the Biodex 840-000 Multi Joint System Isokinetic Dynamometer (Biodex Medical Systems, Shirley, NY, USA) set to report peak torque at 60° · s of flexion and extension and 180° · s of flexion and extension. Regression analyses indicated that 3 of the 4 strength deficit parameters could be predicted from a linear combination of field test results (p < 0.05). Of the strength deficits measured, hamstring deficits at flexion velocities of both 60° · s and quadriceps strength deficits at 60° · s were those that could be predicted using field test results. The results of this study, by increasing the diagnostic power of the clinician, may make it easier to develop strength training protocols designed specifically to target weak musculature in the lower extremity. This targeting of specific musculature, in an effort to return symmetrical strength to the lower extremity, may ultimately decrease the likelihood of lower extremity injury in college-aged men and women.

Background: Impaired trunk motion during pitching may be a risk factor for upper extremity injuries. Specifically, increased forces about the shoulder and elbow have been observed in pitchers with excessive contralateral trunk lean during pitching. Because of the difficulty in identifying abnormal trunk motions during a high-speed task such as pitching, a clinical screening test is needed to identify pitchers who have impaired trunk motion during pitching. Hypothesis/Purpose:The purpose of this study was to determine the relationship between the degree of lateral trunk lean during the single-leg squat and amount of trunk lean during pitching and if trunk lean during pitching can be predicted from lean during the single-leg squat.Study Design: Controlled Laboratory Study; Cross-sectional.Methods: Seventy-three young baseball pitchers (11.4 ± 1.7 years; 156.3 ± 11.9 cm; 50.5 ± 8.8 kg) participated. An electromagnetic tracking system was used to obtain trunk kinematic data during a single-leg squat task (lead leg) and at maximum shoulder external rotation of a fastball pitch. Pearson correlation coefficients for trunk lean during the single-leg squat and pitching were calculated. A linear regression analysis was performed to determine if trunk lean during pitching can be predicted from lean during the single-leg squat.Results: There was a positive correlation between trunk lean during the single-leg squat and trunk lean during pitching (r= 0.53; p<0.001). Lateral trunk lean during the single-leg squat predicted the amount of lateral trunk lean during pitching (R 2 = 0.28; p< 0.001).Conclusions: A moderate positive correlation was observed between trunk lean during an SLS and pitching. Trunk lean during the single-leg squat explained 28% of the variance in trunk lean during pitching. Level of Evidence: Diagnosis, level 3