The etiology of Little League Elbow involves the high valgus torque of the throwing motion, which generates tensile and shearing stresses at the medial elbow.1 The apophyseal cartilage at the medial epicondyle sustains repetitive trauma, which leads to the injury.2 Repetitive microtrauma may cause this injury due to insult at the hypertrophic zone of cartilage, which is active during adolescent growth spurts.1 It is commonly sustained by baseball pitchers between 9 and 14 years old.3 The medical epicondyle may arise from more than one ossification center and is commonly the last epiphyseal center to fuse with the humeral shaft, sometimes as late as 15 or 16 years of age.4 The medial epicondyle serves as the attachment site of the flexor muscle origins and the ulnar collateral ligament. In this age group, the apophysis is the area of highest potential for injury or disruption, whereas similar forces in a skeletally mature athlete may result in an ulnar collateral ligament tear or medial epicondylitis.
Little League Elbow is seen more commonly in boys. This is likely due to their increased participation in youth baseball and the specific forces that act on their hypertrophic cartilage during the throwing motion. It is also seen in other sports that involve overhead throwing mechanics, including polo, volleyball, and football (especially among quarterbacks). However, similar conditions are seen in male and female athletes in other regions of the body, such as distal radial epiphysitis, olecranon apophysitis, proximal humeral epiphysitis (Little League Shoulder), iliac apophysitis, tibial tubercle apophysitis (Osgood-Schlatter Disease), apophysitis of the os calcis (Sever’s Disease), and apophysitis of the proximal fifth metatarsal (Iseline’s Disease).1
Risk factors for development of Little League Elbow include age, activity level (pitch count), and position. Pitchers are at greatest risk, followed by catchers, infielders, and least often outfielders.4 Catchers often do not have limitations on pitch counts received but may sustain injury to the medial epicondyle due to the increased stress placed on the elbow when throwing from a squatted position.5 The condition occurs most commonly in the dominant arm and in youth with a family history of osteochondrosis.4
Patients with Little League Elbow present with medial elbow pain and may complain of loss of velocity or strength. They may also have an objective decreased throwing distance. Common findings on physical examination include point tenderness over the medial epicondyle and hypertrophy over the medial epicondyle.5 Pain is often insidious in onset, and the injury goes unreported until progressive throwing leads to increased pain and a loss of power or control. Pain is exacerbated during early and late cocking of throwing motion.4 Sudden onset or a “pop” may indicate an avulsion.
Physical examination should include bilateral comparison of the elbows, with attention to the presence of swelling and tenderness. Range of motion should be full; flexion contracture greater than 15° is consistent with an avulsion fracture,4 as is ecchymosis. Ulnar collateral ligament integrity should be tested with valgus stress applied at 20° of elbow flexion. Neurologic sensation should be normal, with attention to sensation along the ulnar nerve distribution, including testing of Tinel’s sign at the cubital tunnel and interosseous muscle strength of the hand (dorsal abductors and palmar adductors) to rule out ulnar nerve injury.
Anteroposterior and lateral radiographic views should be obtained in patients with athletic elbow injuries, especially if there is decreased range of motion.4 Bilateral studies are helpful for comparison. Plain films may demonstrate widening of the growth plate or irregularity of the medial epicondyle ossification center but are normal in many cases. Radiographs should be assessed for presence of an avulsed epicondylar fragment or anterior and posterior fat pads (“sail sign”), which signify the presence of an effusion. Any concern for ulnar collateral ligament tear or laxity should be promptly evaluated with magnetic resonance imaging.
The key component of treatment involves restriction from throwing. Commonly, a minimum period of 4 to 6 weeks of rest is needed.1 Gradual return to throwing may be undertaken if the patient is asymptomatic following this prescribed rest period, with avoidance of aggravating pitches, specific restrictions of pitch counts, and attention to pitching mechanics.1
Patients who are caught early and have a mild case may be allowed to bat and play an infield position that involves less throwing, such as first base. More recalcitrant cases may require a period of immobilization or, in the case of significantly displaced avulsion injuries, operative reduction and fixation. A rehabilitation program, including a graduated return to throwing protocol, is often needed to restore strength and endurance.
Prevention of Little League Elbow is focused on adherence to pitch counts and limitation of breaking pitches such as the screwball, curve ball, and slider before 14 years of age.3,4,6–9 Little League Baseball and USA Baseball detail specific numbers of pitch counts allowed by age level.6,9 Warm-up pitches are not included in pitch counts; however, rules permit a returning pitcher to have 8 preparatory pitches or 1 minute per inning, whichever comes first.9
There are no limitations on the number of innings a pitcher should play; however, Little League Baseball does not allow a pitcher to pitch in more than 1 game per day.9 USA Baseball suggests that pitch count recommendations can be converted into batter limitation by dividing by 5.6 Both organizations agree that absolute pitch counts are the most accurate way to prevent injury.
Little League Baseball also has recommendations regarding “a game of rest” from pitching after exceeding a certain number of pitches, and it recommends that a retiring pitcher not take over as the catcher for the team.9 Furthermore, it is often recommended by Little League Baseball that a pitcher have 3 days of rest from the position of pitcher following a game spent pitching. The rest period does not begin until midnight of the day pitched; it does not matter if the game was in the morning. The American Sports Medicine Institute and USA Baseball further recommend against year-round pitching so that baseball pitchers have a period of “active rest” between their seasons.9
Two recent studies have demonstrated that the velocity of pitches may be just as important in injury causation at the elbow and shoulder. Specifically, there was higher moment measured at the elbow and shoulder joints with fastballs compared with curveballs.10,11 However, this should not be taken as a clearance for younger players to throw breaking pitches.
These pitches have been associated with increased rates of injury as well, and even Dr. Andrews of the American Sports Medicine Institute stated “It [the American Sports Medicine Institute study] may do more harm than good—quote me on that.... There are still some unknown questions.”12 An area of baseball where there is near uniform agreement is the strict adherence to pitch counts based on age. There does seem to be convincing evidence that limitation of pitch counts can decrease or prevent injury. An example is shown in the Table.
Table: Pitch Count Recommendations by Age
Little League Elbow is an often preventable overuse injury to the medial epicondylar growth plate in skeletally immature athletes. Due to its insidious presentation, coaches and parents should be educated to recognize the signs and symptoms of this condition. Athletic trainers, physicians, and health care providers covering baseball may assist not only in prevention, but also in early recognition of Little League Elbow.
Athletes should never be encouraged to throw through pain. Athletes younger than 14 years old should not attempt or be encouraged to throw breaking pitches. Recently, the importance of pitch velocity and the association of greater injury rates with fastball pitches has become an area of concern. More research is likely to be done in the future to continue to delineate injury mechanics and association. With proper recognition, followed by rest and gradual return to activity, Little League Elbow is often self-limited, heals well, and will allow a resumption of normal activity levels and pitch velocity.
- Frush TJ, Lindenfeld TN. Peri-epiphyseal and overuse injuries in adolescent athletes. Sports Health. 2009;1:201–211.
- Cain EL Jr, Dugas JR, Wolf RS, Andrews JR. Elbow injuries in throwing athletes: A current concepts review. Am J Sports Med. 2003;31:621–635.
- Children’s Memorial Hospital, Sports Medicine. “Little League elbow” (medial epicondylar apophysitis). Children’s Memorial Hospital Web site. http://www.childrensmemorial.org/depts/sports-medicine/little-league-elbow.aspx. Accessed April 8, 2010.
- Lin S, Crovetti G, Hosey RG, Armsey TD. Little leaguer’s elbow (medial epicondylitis/apophysitis). In: Bracker MD (ed.). 5 Minute Sports Medicine Consult. Philadelphia, PA: Lippincott Williams & Wilkins; 2001:342–343.
- Hang DW, Chao CM, Hang YS. A clinical and roentgenographic study of Little League elbow. Am J Sports Med. 2004;32:79–84. doi:10.1177/0095399703258674 [CrossRef]
- American Sports Medicine Institute. 2006. USA Baseball Medical & Safety Advisory Committee Guidelines: May 2006. American Sports Medicine Institute Web site. http://www.asmi.org/asmiweb/usabaseball.htm#Counts. Accessed April 8, 2010.
- Lyman S, Fleisig GS, Andrews JR, Osinski ED. Effect of pitch type, pitch count, and pitching mechanics on risk of shoulder pain in youth baseball pitchers. Am J Sports Med. 2002;30:463–468.
- Mehlhoff TL, Bennett JB. Sports specific problems: Elbow injuries; little league elbow. In: Mellion MB, Walsh WM, Madden C, Putukian M, Shelton GL, eds. Team Physician’s Handbook. 3rd ed. Hanley & Belfus; 2002:423–424.
- Little League Pitch Count Questions and Answers: Revised for 2008. Little League Online. http://www.littleleague.org/Assets/forms_pubs/PitchCount_faq_08.pdf. Accessed April 8, 2010.
- Nissen CW, Westwell M, Ounpuu S, et al. A biomechanical comparison of the fastball and curveball in adolescent baseball pitchers. Am J Sports Med. 2009;37:1492–1498. doi:10.1177/0363546509333264 [CrossRef]
- Dun S, Loftice J, Fleisig GS, Kingsly D, Andrews JR. A biomechanical comparison of youth baseball pitchers: is the curve-ball potentially harmful?Am J Sports Med. 2008;36:686–692. doi:10.1177/0363546507310074 [CrossRef]
- Hyman M. Studies show that the curve-ball isn’t too stressful for young arms. The New York Times. http://www.nytimes.com/2009/07/26/sports/baseball/
Pitch Count Recommendations by Age
|PITCHING LIMIT||9 TO 10 YEARS||11 TO 12 YEARS||13 TO 14 YEARS|
|Pitches per game||50||75||75|
|Pitches per week||75||100||125|
|Pitches per season||1000||1000||1000|
|Pitches per year||2000||3000||3000|