title: [Acute and overuse injuries in soccer - what about the evidence level?].
abstract: OBJECTIVE
  Over the last years, several studies on harmful events (h. e.) in soccer have been published. The aim was to develop a ranking of these studies according to their evidence, and to analyse the data with respect to the number of study participants, athletes' status, gender distribution, and genesis of harmful events in soccer.
  
  
  METHODS
  Between 1976 and 2011, the data bases MEDLINE, EBMR, and SPOTLIT were scanned by the keywords/combinations: soccer, acute injuries, overuse injuries, training, and match. In doing so, 644 initially potential relevant articles were found. On the basis of the QUORUM standard, 78 potentially relevant articles were filtered out, and an EVIDENCE BASED LEVEL (EBL) was assigned. The results were rated according to importance and shown descriptively, because the heterogeneity of the study inhibited meta-analytical evaluation.
  
  
  RESULTS
  23 % of the publications could be assigned to EBL 2a - 2c, 27 % to EBL 3a and 3b, and 50 % to EBL 4 and 5. The studies comprised altogether 22 294 male and 2375 female athletes; 87 % of the male and 29 % of the female were professional athletes. 7 usable publications with a total of 8011 h. e. in men and 6 publications with 1055 h. e. in women dealt with contact/non-contact genesis of h. e.. 46 % male (72 % female) athletes suffered from h. e. caused by contact events, and 54 % male (28 % female) athletes suffered from h. e. caused by non-contact events. The distribution of acute and overuse injuries was analysed in 9969 h. e. in men (11 publications), and in 624 h. e. in women (5 publications). On average, the number of acute injuries (90 % male, 86 % female) was much higher than that of overuse injuries. The prevalence of h. e. with respect to training or match playing was analysed in 11 studies with 10 078 h. e. in men, and in 4 studies with 546 harmful events in women. 35 % of men's h. e. occurred during training and 65 % during matches, whereas 60 % of the women's h. e. occurred during training and 40 % during matches.
  
  
  CONCLUSIONS
  The number of athletes included in the studies is quite low in relation to the number of active athletes. Studies of professional athletes are over-represented. Independent of gender, there are more acute injuries than overuse injuries, whereas the distribution of harmful events with respect to genesis and occurrence during training and match is gender-specific. The studies' evidence level is quite low in relation to the socio-economic significance of this kind of sport; the studies' evidence is higher for women.
authors.affiliation: Chirurgisch-Orthopädisches Medizinisches Versorgungszentrum Illingen, Illingen/Saar.
authors.forename: J
authors.initials: J
authors.lastname: Kelm
authors.affiliation: Sportwissenschaftliches Institut der Universität des Saarlandes, Saarbrücken.
authors.forename: O
authors.initials: O
authors.lastname: Ludwig
authors.affiliation: Institut für Radiologie, Kantonsspital Baden AG, Baden, Schweiz.
authors.forename: F
authors.initials: F
authors.lastname: Ahlhelm
authors.affiliation: Knappschaftsklinikum Saar Krankenhaus Püttlingen, Klinik für Innere Medizin, Püttlingen/Saar.
authors.forename: B
authors.initials: B
authors.lastname: Andre
authors.affiliation: Klinik für Unfall-, Hand- und Wiederherstellungschirurgie, Universitätsklinikum des Saarlandes, Homburg/Saar.
authors.forename: S
authors.initials: S
authors.lastname: Hopp
mesh_terms: D000208:Acute Disease; D017677:Age Distribution; D054874:Athletic Performance / Q000706:statistics & numerical data*; D012090:Cumulative Trauma Disorders / Q000453:epidemiology*; D019317:Evidence-Based Medicine; D005260:Female; D006801:Humans; D008297:Male; D064797:Physical Conditioning, Human / Q000706:statistics & numerical data*; D015995:Prevalence; D012307:Risk Factors; D017678:Sex Distribution; D012916:Soccer / Q000293:injuries* / Q000706:statistics & numerical data*