title: Prevalence and Clinical Characteristics of Osteochondritis Dissecans of the Humeral Capitellum Among Adolescent Baseball Players.
abstract: BACKGROUND
  The prevalence and clinical characteristics of osteochondritis dissecans (OCD) of the humeral capitellum among adolescent baseball players are unknown.
  
  
  OBJECTIVE
  To determine the OCD prevalence in adolescent competitive baseball players and to investigate the clinical characteristics of these patients.
  
  
  METHODS
  Cross-sectional and case-control study; Level of evidence, 3.
  
  
  METHODS
  A total of 2433 baseball players (mean age, 14.5 ± 1.5 years) belonging to junior high school and high school baseball clubs were enrolled. Players completed a questionnaire, and the elbow of each player's throwing arm was assessed by ultrasonography. Participants with abnormal results on ultrasonography were further examined through radiographic study. The OCD lesions were classified into stages based on radiographic results, and demographic data were compared between players with and without OCD lesions.
  
  
  RESULTS
  Osteochondritis dissecans of the humeral capitellum was found in 82 (3.4%) elbows by ultrasonography. Players with an OCD lesion began playing baseball at an earlier age (P = .016), had a longer duration of competitive play (P = .0013), and had experienced more present (P = .0025) and past (P < .0001) elbow pain compared with players without a lesion. There were no differences between the 2 groups in the position played (P = .26). Sixty-eight patients underwent further radiographic examination for OCD (radiography, computed tomography, magnetic resonance imaging). Of these players, 10 (14.7%) were classified as having stage I OCD (radiolucent stage); 26 (38.2%), stage II (fragmentation stage); 9 (13.2%), stage III (loose body stage); 9 (13.2%), stage IV (residual stage); and 14 (23.5%), stage V (postoperative stage).
  
  
  CONCLUSIONS
  The prevalence of OCD of the humeral capitellum, including latent cases, was 3.4% among adolescent baseball players. Players with OCD lesions began playing baseball at earlier ages, had played for longer periods, and had experienced more elbow pain. The player's current baseball position may not be related to the existence of OCD lesions in adolescents.
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kida
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Morihara
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kotoura
authors.affiliation: Faculty of Health and Sports Science, Doshisha University, Kyoto, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Hojo
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Hisakazu
authors.initials: H
authors.lastname: Tachiiri
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Sukenari
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Iwata
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Ryuhei
authors.initials: R
authors.lastname: Furukawa
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Oda
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Arai
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan fjwr@koto.kpu-m.ac.jp.
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Fujiwara
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan Department of Rehabilitation, University Hospital, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Kubo
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D001484:Baseball / Q000293:injuries*; D016022:Case-Control Studies; D003163:Competitive Behavior; D003430:Cross-Sectional Studies; D004551:Elbow Joint / Q000503:physiopathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010008:Osteochondritis Dissecans / Q000175:diagnosis / Q000453:epidemiology* / Q000601:surgery; D010146:Pain / Q000209:etiology; D015995:Prevalence; D012307:Risk Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: adolescent; baseball; elbow; osteochondritis dissecans; prevalence; ultrasonography