Proximal humeral epiphysiolysis (a.k.a. Little League shoulder) is most commonly seen in adolescent throwing athletes from ages 11 to 16 years (1,4). The pathology is a widening of the physis, resulting in a Salter-Harris I fracture (see Figure) (8). Biomechanically, due to weaker developing epiphyseal plates, torque during maximum external shoulder rotation and excessive laxity may predispose the young thrower to this type of injury (9,10).
Important information to elicit includes whether the athlete is a pitcher or catcher, the number and type of pitches thrown per game and season, the frequency of pitching, and the number of leagues in which the athlete competes. The quality, severity, and specific location of pain experienced as well as when the pain occurs during pitching motion are important information to obtain (4). Patients typically present with pain occurring in the shoulder that has progressively worsened over several months while throwing hard (1). The most consistent physical examination finding is tenderness over the proximal humeral physis (1).
While anterior-posterior radiographs in internal and external rotation with widening of the proximal humeral physis is the hallmark of Little League shoulder, there also may be fragmentation of the lateral metaphysis, sclerosis, cystic changes, and demineralization of the proximal humeral metaphysis (2). Additionally, widening of the physis does not necessarily correlate to symptoms. An important pearl is to always obtain comparison radiographs of the nonthrowing shoulder. Magnetic resonance imaging (MRI) studies also have been used for further imaging detail with success (2). However, MRI is typically not indicated unless there is suspicion of additional injury and/or no improvement with rest for at least 3 wk (3).
Nonoperative treatment typically begins with 6 wk of complete rest. If the patient is asymptomatic at rest, nonthrowing physical therapy may begin at week 7. At 3 months, if asymptomatic, a progressive throwing program with subsequent return to play is standard.
Overuse throwing injury can be minimized by following national recommendation guidelines, which major league baseball has now endorsed, on pitch counts, rest days, pitch type based on age, use of radar guns, and yearly arm rest recommendations (4–7,11).
1. Carson WG Jr, Gasser SI. Little leaguer’s shoulder. A report of 23 cases. Am. J. Sports Med.
1998; 26: 575–80.
2. May MM, Bishop JY. Shoulder injuries in young athletes. Pediatr. Radiol.
2013; 43: S135–40.
3. Obembe OO, Gaskin CM, Taffoni MJ, Anderson MW. Little leaguer’s shoulder (proximal humeral epiphysiolysis): MRI findings in four boys. Pediatr. Radiol.
2007; 37: 885–9.
4. Osbahr DC, Kim HJ, Dugas JR. Little league shoulder. Curr. Opin. Pediatr.
2010; 22: 35–40.
5. Pitch Smart USA Baseball Web site [Internet]. Available from: http://m.mlb.com/pitchsmart
. Accessed 2014 Nov 18.
6. Parks ED, Ray TR. Prevention of overuse injuries in young baseball pitchers. Sports Health
. 2009; 1: 514–7.
7. Ray TR. Youth baseball injuries: recognition, treatment, and prevention. Curr. Sports Med. Rep.
2010; 9: 294–8.
8. Robinson TW, Corlette J, Collins CL, Comstock RD. Shoulder injuries among US high school athletes, 2005/2006-2011/2012. Pediatrics
. 2014; 133: 272–9.
9. Sabick MB, Kim YK, Torry MR, et al. Biomechanics of the shoulder in youth baseball pitchers: implications for the development of proximal humeral epiphysiolysis and humeral retrotorsion. Am. J. Sports Med.
2005; 33: 1716–22.
10. Walton J, Paxinos A, Tzannes A, et al. The unstable shoulder in the adolescent athlete. Am. J. Sports Med.
2002; 30: 758–67.
11. Zaremski JL, Krabak BJ. Shoulder injuries in the skeletally immature baseball pitcher and recommendations for the prevention of injury. PM R
. 2012; 4: 509–16.