Progressive Elbow Magnetic Resonance Imaging Abnormalities in Little League Baseball Players Are Common: A 3-Year Longitudinal Evaluation

Abstract

Background: Prior studies have revealed magnetic resonance imaging (MRI) evidence of elbow pathology in single-season evaluation of competitive youth baseball players. The natural history of these findings and risk factors for progression have not been reported. Purpose: To characterize the natural history of bilateral elbow MRI findings in a 3-year longitudinal study and to correlate abnormalities with prior MRI findings, throwing history, playing status, and physical examination. Study Design: Cohort study; Level of evidence, 2. Methods: A prospective study of Little League players aged 12 to 15 years was performed. All players had preseason and postseason bilateral elbow MRI performed 3 years before this study. Players underwent repeat bilateral elbow MRI, physical examination, and detailed assessment of throwing history, playing status, and arm pain. Imaging was read by a blinded musculoskeletal radiologist and compared with prior MR images to assess for progression or resolution of previously identified pathology. Results: All 26 players who participated in the previous single-season study returned for a 3-year assessment. At the completion of the study, 15 players (58%) had dominant arm MRI pathology. Eighty percent (12/15 players) of MRI findings were new or progressive lesions. Players with postseason MRI pathology at the beginning of the study were more likely to have MRI pathology at the 3-year follow-up than players with previously normal postseason MRI ( P < .05), although 6 of the 14 players (43%) with previously normal MRI developed new pathology. Year-round play was a significant predictor of tenderness to elbow palpation ( P = .027) and positive MRI findings at 3 years ( P = .047). At the 3-year follow-up, 7 players (27%) reported having throwing elbow pain and 3 had required casting. Additionally, differences were noted in the dominant arm’s internal and external rotation in those that continued to play baseball ( P < .05). Conclusion: Dominant elbow MRI abnormalities are common in competitive Little League Baseball players. Year-round play imparts significant risk for progression of MRI pathology and physical examination abnormalities.

Optogenetic-induced muscle loading leads to mechanical adaptation of the Achilles tendon enthesis in mice

“…( 65 ) showed that the expression of integrins in tendon did not correlate with the increase of loading dose, suggesting an overuse-induced ECM damage that regulates mechanosensitivity. Our findings model the structural and mechanical changes similar to those occurring in pediatric apophyseal pathologies and in young athletes ( 66 , 67 ). This study provides the first small animal model of pediatric apophyseal pathologies and can be leveraged for future systematic examination of mechanisms of injury and repair in the growing skeleton.…”

Risk factor for elbow symptom manifestation in young baseball players with asymptomatic medial elbow abnormalities: a prospective cohort study

“…However, the authors did not find significant correlations between progressive abnormal MRI findings and throwing history (including years of play, primary position of play, months of play per year, and physical examination findings, such as shoulder ROM, shoulder strength, and shoulder and elbow instability). Holt et al 11 also reported that year-round play was a significant predictor of positive MRI findings at 3 years; however, the MRI findings included both new lesions and pre-existing lesions, which do not reflect the progression of abnormal MRI findings. Thus, it remains unclear which factors influence the progression of elbow abnormalities on US or MRI.…”

“…Holt et al 11 prospectively evaluated the progression of MRI-detected elbow abnormalities in 26 Little League players (aged 12 to 15 years) to determine whether pitchers, catchers, or year-round players (defined as ≥ 8 months per year) with continued play would have more severe and progressive elbow abnormalities on MRI at the 3-year follow-up. The authors found that 57.7% of players displayed dominant elbow MRI pathology at the 3-year follow-up, with 80.0% of these patients developing new or progressive abnormal findings, compared to the findings of prior MRI studies.…”

Common Upper Extremity Injuries in Pediatric Athletes

“…This injury occurs almost exclusively in throwing athletes such as baseball players, during the cocking phases of throwing when valgus stress on the medial elbow is maximal [ 8 , 10 , 11 ]. Approximately 20–50% of youth baseball players report elbow pain, and recent radiographic assessments of the medial elbow using ultrasonography and MRI have reported medial epicondyle abnormalities ranging from 10 to 50% on the throwing side [ 2 , 3 , 30 •, 31 – 36 ].…”