Increase in ACL and PCL injuries after implementation of a new professional football league.

Purpose: In the season 2008-2009, a third professional football league was established in Germany. This study analysed the influence of increased training and playing intensity on severe knee injuries in football players.
Methods: In a prospective controlled one-season trial, injury incidence and injury patterns of players of the newly established professional football league were analysed, particularly with regard to ruptures of the anterior (ACL) and posterior (PCL) cruciate ligaments. Players of the highest amateur level served as a control group.
Results: Four hundred and eight players of 24 teams were allocated to two groups. The overall training exposure was significantly (p < 0.001) higher in the new professional league (335.3 h per player) than at the amateur level (286.6 h per player). Players at both levels showed similar overall injury rates and injury patterns. However, players in the professional league had a significantly higher (p = 0.04) incidence of ACL and PCL injuries, than players at the amateur level. More than 90 % of all ACL and PCL ruptures in both groups were sustained by players, who had played at least one level lower in the previous season. In addition, injuries of players who had sustained repeat injuries over the season were more severe.
Conclusion: The introduction of a new professional football league increased the training and playing intensity of players as well as the number of ACL and PCL ruptures. A specific injury prevention concept, particularly for players facing rapidly increasing training and playing intensity, seems to be mandatory.
Level of Evidence: Prospective controlled cohort study, Level II.