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A systematic review of different jump-landing variables in relation to injuries.

AIM
Injuries of the lower extremity tend to be associated with jump-landing movements. This review provides an overview of the kinematic variables and malalignments during jump-landing, which could be attributed to overuse or acute injury occurrence.


METHODS
We searched ISI Web of Knowledge, SPORTDiscus, PubMed, EMBASE and SCOPUS for all studies, published before October 2012, which looked at the relation between kinematic risk factors and malalignments of jump-landing and injuries. An article was included 1) if the article was an observational, retrospective or prospective study; 2) if the article investigated the relationship between injuries and the visible and easily measurable kinematic variables or malalignments of the jump-landing technique; 3) if the article met a predefined quality cut-off score.


RESULTS
Ten studies met all inclusion criteria. Literature shows that several kinematic factors are related to lower acute and overuse injuries.


CONCLUSION
A stiffer jump-landing technique is a risk factor in the development of overuse injuries and acute injuries. This is caused by less active motion in the lower extremity joints and by the increased valgus position of the knee during the jump-landing maneuver which creates an unfavorable alignment of the lower extremity. A valgus position of the knee during landing was also a predictor of acute lower extremity injuries. Future intervention programs should focus on the jump-landing technique and the performance of the athlete.