title: Lumbar intervertebral disk degeneration in athletes.
abstract: BACKGROUND
  Several studies have reported that physical loading related to competitive sports activities is associated with lumbar intervertebral disk degeneration. However, the association between types of sports activities and disk degeneration has not been clarified.
  
  
  OBJECTIVE
  The frequencies of disk degeneration may vary with the competitive sport because of the different postures and actions specific to each sport.
  
  
  METHODS
  Cross-sectional study (prevalence); Level of evidence, 3.
  
  
  METHODS
  Study participants were 308 well-trained university athletes (baseball players, basketball players, kendo competitors, runners, soccer players, swimmers) and 71 nonathlete university students (reference group). Disk degeneration was evaluated using T2-weighted magnetic resonance imaging. A self-reported questionnaire concerning low back pain was also conducted.
  
  
  RESULTS
  The proportions of the participants who had disk degeneration among the baseball players (odds ratio, 3.23) and the swimmers (odds ratio, 2.95) were significantly higher than among the nonathletes using logistic regression analysis. When all patients were grouped together, the association between lifetime experience of low back pain and participants with disk degeneration was significant, and a linear association between the degree of severest low back pain experienced and participants with disk degeneration, analyzed by a Cochran-Mantel-Haenszel test, was also significant.
  
  
  CONCLUSIONS
  Continuous competitive baseball and swimming activities during youth may be associated with disk degeneration. Furthermore, the study indicates that the experience of severe low back pain might be a predictor of disk degeneration in youth. The authors hope that preventive measures and management to protect against disk degeneration and low back pain in athletes will be established by further studies based on these results.
authors.affiliation: Department of Orthopaedic Surgery, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan. seikei@md.tsukuba.ac.jp
authors.forename: Mika
authors.initials: M
authors.lastname: Hangai
authors.forename: Koji
authors.initials: K
authors.lastname: Kaneoka
authors.forename: Shiro
authors.initials: S
authors.lastname: Hinotsu
authors.forename: Ken
authors.initials: K
authors.lastname: Shimizu
authors.forename: Yu
authors.initials: Y
authors.lastname: Okubo
authors.forename: Shumpei
authors.initials: S
authors.lastname: Miyakawa
authors.forename: Naoki
authors.initials: N
authors.lastname: Mukai
authors.forename: Masataka
authors.initials: M
authors.lastname: Sakane
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Ochiai
mesh_terms: D000293:Adolescent; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000473:pathology*; D007564:Japan / Q000453:epidemiology; D017116:Low Back Pain / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D013177:Sports; D011795:Surveys and Questionnaires; D016474:Weight-Bearing / Q000502:physiology; D055815:Young Adult