A biomechanical analysis of youth pitching mechanics.
ABSTRACT It is estimated that nearly 6% of youth baseball participants seek medical attention for injuries sustained during play. Most injuries are overuse injuries, and 26% are to the shoulder or upper arm. By quantifying youth pitching biomechanics, knowledge can be gained concerning the manner in which these injuries are sustained during play.
Sixteen healthy right hand-dominant baseball pitchers participated in this study. After digitization of 21 bony landmarks, kinematic calculations were conducted using the 3-dimensional coordinates from each video frame. Data were time normalized, forcing major temporal components of the movement to occur at specific intervals. Segment-based reference frames were established, and resultant joint kinetics were projected onto each reference frame. Kinetic data were normalized and calculated along or about the anterior/posterior, medial/lateral, and proximal/distal axes.
Maximum trunk rotation and external shoulder rotation were observed during arm cocking. Each of the remaining kinematic parameters peaked after ball release. All maximum values for joint kinetics were measured during arm cocking with the exception of compressive forces experienced at the shoulder and elbow, which peaked after the instant of ball release.
Data produced in this study indicate that youth pitchers initiate trunk rotation early in the movement, which can lead to shoulder hyperangulation. Opposing torques at each end of the humerus also produce a large net torque about the longitudinal axis of the humerus during late arm cocking and may increase humeral retrotorsion in youth pitchers. Underdeveloped musculature in the rotator cuff may lead to difficulty controlling throwing-arm deceleration, causing an increase in horizontal adduction across the torso.
An improved understanding of youth pitching mechanics is gained from the data collected, analyzed, and discussed in this study. Through increases in the knowledge pertaining specifically to the mechanics of youth pitchers, the opportunity to develop pitching mechanics specifically designed for preventing injuries in little league pitchers arises.
This study is a Level 4 study describing youth pitching biomechanics and how they relate to possible injuries.
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ABSTRACT: Pitchers may be at greater risk of injury in comparison to other overhead throwing athletes due to the repetition of the pitching motion. It has been reported that approximately 30% of all baseball injuries occur in the lower body. This may be related to limited hip mobility, which can compromise pitching biomechanics while placing excessive stress on the trunk and upper quarter. Hip motion and strength measurements have been reported in professional baseball pitchers but have not been reported in collegiate pitchers. The purpose of this study was to report preliminary findings for passive hip motion and isometric hip muscle strength in collegiate pitchers and compare them to previously published values for professional level pitchers. Cross sectional study. Twenty-nine collegiate baseball pitchers (age = 20.0 + 1.4 years, height = 1.88 + 0.06 m; weight = 89.3 + 10.7 kg; body mass index = 25.3 + 2.5 kg/m2) were recruited. Subjects were assessed for hip internal rotation (IR) and external rotation (ER) passive motion, hip anteversion or retroversion, gluteus maximus, gluteus medius, hip internal rotator, hip external rotator strength, and lumbo-pelvic control with the prone active hip rotation test as described by Sahrmann. Statistical analysis included calculation of subject demographics (means and SD) and use of a two-tailed t-test (p >0.05). Fifty-two percent of the right-handed and 50% of the left-handed pitchers demonstrated poor lumbo-pelvic motor control with an inability to stabilize during active hip IR and ER even though isolated strength deficits were not detected at a significant level. There were no significant differences in hip passive motion or gluteus medius strength between right and left-handed pitchers. Differences did exist between collegiate data and previously published values for professional pitchers for IR motion measured in prone and gluteus maximus strength. Hip retroversion was present in 55% of the pitchers primarily in both limbs with four of the pitchers presenting with retroversion singularly in either the stride or trail limb where the ER rotation motion was greater than the IR. Assessing mobility and muscle strength of the lower quarter in isolation can be misleading and may not be adequate to ensure the potential for optimal pitching performance. These findings suggest that lumbo-pelvic control in relation to the lower extremities should be assessed as one functional unit. This is the first study to explore hip motion, strength, and lumbo-pelvic control during active hip rotation in collegiate baseball pitchers. 2.
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ABSTRACT: Overuse injuries of the shoulder and elbow are common in the skeletally immature throwing athlete. This review goes beyond describing the classic imaging findings of Little League shoulder and elbow and probes deeper into new insights suggesting a unifying etiology of metaphyseal or metaphyseal equivalent injury as the cause of many of the bony lesions described. Injury patterns change depending on the athlete's skeletal maturation, and the spectrum of abnormalities is reviewed.Seminars in musculoskeletal radiology 11/2014; 18(5):469-77. DOI:10.1055/s-0034-1389264 · 0.95 Impact Factor
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ABSTRACT: Adolescent baseball players, especially pitchers, are at increased risk for shoulder and elbow injuries as their level of competition increases. The intersection of the adolescent growth spurt with the high levels of elbow valgus and shoulder rotational torques placed upon the arm during overhand pitching predisposes the shoulder and elbow to physeal injuries. Little League shoulder and Little League elbow syndromes most commonly represent pathology at the physeal regions of the proximal and distal humerus and proximal ulna sustained from repetitive loads caused by overhead throwing. There is a growing understanding that these injuries occur on a wide spectrum from delayed physeal closure and physeal widening to acute transphyseal fracture. Although operative intervention is infrequently required, patient and parent counseling can be complex. Health care professionals who care for adolescent baseball players also can play an important role in prevention. Appropriate counseling requires a comprehensive understanding of the clinical, radiographic, and biomechanical aspects of these injuries. This review summarizes these major concepts, focusing on the best available evidence from recent biomechanical and clinical studies on shoulder and elbow injuries in adolescent baseball pitchers.The Physician and sportsmedicine 09/2014; 42(3):100-111. DOI:10.3810/psm.2014.09.2081 · 1.49 Impact Factor