Fig. 1 Radiographic classification of osteochondrosis of the humeral capitellum. Stage I was characterized by translucency (left). In stage II, nondisplaced fragments were present (middle). Loose bodies and sclerotic change indicated stage III (right). Reproduced with permission from Matsuura T, Kashiwaguchi S, Iwase T, Takeda Y, Yasui N: Conservative treatment for osteochondrosis of the humeral capitellum. Am J Sports Med, 2008, in press.


Published 5/1/2008
Carolyn Rogers

Elbow overuse injuries common in young baseball players

Elbow overuse injuries are on the rise among young baseball players, according to a paper presented at the 75th AAOS Annual Meeting in San Francisco.

“Our study found that 40 percent of child and adolescent baseball players had elbow pain and about 20 percent had osteochondral lesions,” reported Tetsuya Matsuura, MD. “The medial epicondyle was the most vulnerable area.”

Tournament players examined
“We examined the elbow joints of 1,802 baseball players at a summer tournament in Japan in 2006,” Dr. Matsuura said. The average age of the players was 10.7 years (range: 8 to 12 years old). Both boys and girls were included in the study.

The three-step examination process included a questionnaire, a physical examination, and a radiographic examination.

Approximately 2 weeks prior to the tournament, the players completed a questionnaire regarding their age, hand dominance, playing position, years of playing, numbers of pitches, and pain during or after throwing practice.

Of the 1,802 young baseball players, 717 (39.8 percent) reported elbow pain. These players then received a physical examination of the elbows—including range of motion, tenderness, and valgus stress test; 482 (67.2 percent) had range-of-motion limitations, tenderness of the elbow, or valgus stress pain.

Radiographic examination of both elbows was recommended for 150 players (Fig. 1). Of these, 121 players (80.7 percent) were found to have osteochondral lesions. Although osteochondrosis of the medial epicondyle was most commonly found, lesions on the capitellum and trochlea were also identified.

“Young individuals possess an elbow complex composed of epiphyseal plates that continue to develop until the age of 17,” Dr. Matsuura said. “The problem with most young baseball players centers on the physis (in the pitching arm), which has been identified as the weakest link in the musculotendinous unit in the child and adolescent. Our results support this theory.”

Dr. Matsuura’s co-investigators were Shinji Kashiwaguchi, MD; Takenobu Iwase, MD; Naoto Suzue, MD; and Natsuo Yasui. Disclosure information for the authors can be found online at

Carolyn Rogers is a staff writer for AAOS Now. She can be reached at