Little Leaguer's Shoulder

Little Leaguer's shoulder is a term that sports docs are quite familiar with, yet these same docs often are unable to recall the specifics of the patient presentation that helps distinguish it from other causes of adolescent shoulder pain such as tendinitis. Like many childhood and adolescent articular complaints, it is assumed that at some point comparative radiographs will be ordered in an effort to detect any epiphyseal injury. The problem is that, according to a recent study,¹ the average kid with Little Leaguer's shoulder had symptoms for over seven months before being diagnosed! This recent descriptive study of 23 cases of Little Leaguer's shoulder (LLS) fleshes out the "typical" patient presentation.

Although the exact cause of LLS is unknown, it is known that pitchers are more commonly affected. It is assumed that the strong rotational force imposed on the proximal humeral physis is the primary cause. Yet, it seems to be a timing of elements. Most players are affected during their growth phase (ages 9-16, but primarily ages 11-14). The condition is clearly related to how often the player throws, and to some degree how hard. As players develop higher levels of coordination, the amount of force and frequency of throw increase and coincide with their growth spurt. The proximal humeral physis is at its weakest during this growth spurt.

Although the pivotal evaluation is radiographic, this study indicates that given a specific profile, history and examination findings may provide a fairly accurate diagnostic impression.

Player Profile

• Male pitcher around 14 years of age (basemen second most common, with outfielders and catchers least affected)
  
• Involved in youth or adolescent baseball
  
• Either playing continuously for 12 months on a single team or playing for six months on more than one team
  
• Pain of gradual onset (small percentage had sudden onset)
  
• Pain at the proximal humerus felt only when throwing hard
  
• Pain unrelated to a specific phase of throwing (in most cases)
  
• Pain for an average of seven months (wide range from one week to two years in the current study)

Examination Findings

• Swelling and loss of range of motion are uncommon findings
  
• Tenderness over the proximal humerus is the most consistent finding (specific tenderness over the lateral aspect of the proximal humerus was found in 70% of patients in this study)
  
• In this study, the only weakness detected was in external rotation
  
• Various muscle testing positions increased the pain, however, the two most common were external rotation testing and the "empty can" test (thumbs down abduction)

Radiographic Findings

• The most consistent finding is widening of the proximal humeral physis
  
• Additional findings include demineralization, sclerosis of the proximal humeral metaphysis and fragmentation of the lateral aspect of the proximal humeral metaphysis
  
• Bilateral views are recommended due to the variation in the "look" of the epiphyses
  
• AP internal and external views are recommended (author's note: always consult with a chiropractic or medical radiologist when there is any doubt)
  
• It may take several months for the widening of the proximal humeral physis to "heal" radiographically

Management

Although there is no agreed upon management recommendation, it is clear that rest is essential. How long, however, is debatable. In the current study, an average of three months was used with three caveats.

1. The radiographic "healing" may take longer than three months, however, it should not prevent the initial rehabilitation phase of return to easy throwing;
2. A gradual return to throwing is needed with pain as the limiting factor; and
3. Recovery time varies and in some cases may take as long as 12 months before the pitcher can return to throwing full force (following the season).

In the current study, resistance exercises often caused pain and therefore were not used as a primary approach to the return-to-play rehabilitation prescription. An interval training approach has been developed by Axe et al.² These recommendations are based on age and pitch speed.

Although there are Little League rules regarding how often a pitcher can pitch, what is not often acknowledged are the practice sessions and the player who plays for more than one team. Also, adherence to the rules is variable. A good resource that can be given to coaches and parents is an article by Andrews and Feisig³ on how many pitches should be allowed (written for the parent).

Complications of Little Leaguer's shoulder include the rare avascular necrosis, loose bodies, and early closure of the epiphysis.

Play ball!

References

1. Carson WG, Gasser SI. Little Leaguer's shoulder: a report of 23 cases. Am J Sports Med 1998,26:4;575-580.
2. Axe MJ, Snyder-Mackler L, Konin JG, et al. Development of a distance-based interval throwing program for Little League-aged athletes. Am J Sports Med 1996;24:594-602.
3. Andrew JR, Feisig G. How many pitches should I allow my child to throw? USA Baseball News April 1996, p. 5.