PURPOSE: The purpose of this study was to examine the effect of changing toe direction on knee kinetics and kinematics associated with anterior cruciate ligament injury during drop vertical jumps. METHODS: Fourteen females performed drop vertical jumps under three toe conditions (natural, toe-in, and toe-out). The knee kinetics and kinematics during landing were evaluated using a motion analysis system. Results under three toe conditions were compared using a one-way repeated measures analysis of variance and a post hoc Bonferroni test. RESULTS: Toe-in landing was associated with a significantly greater knee abduction angle, tibial internal rotation angle, and knee abduction moment than the natural and toe-out conditions. Toe-out landing was associated with significantly greater tibial internal rotational angular velocity. CONCLUSIONS: Changing toe direction significantly affects knee kinetics and kinematics during landing. It is important to avoid changing toe direction excessively inward or outward during landing to prevent the increases in knee abduction and tibial internal rotation which might increase the risk of ACL injury. LEVEL OF EVIDENCE: Prognosis, Level IV.
PURPOSE: The purpose of this study was to examine the effect of changing toe direction on knee kinetics and kinematics associated with anterior cruciate ligament injury during drop vertical jumps. METHODS: Fourteen females performed drop vertical jumps under three toe conditions (natural, toe-in, and toe-out). The knee kinetics and kinematics during landing were evaluated using a motion analysis system. Results under three toe conditions were compared using a one-way repeated measures analysis of variance and a post hoc Bonferroni test. RESULTS: Toe-in landing was associated with a significantly greater knee abduction angle, tibial internal rotation angle, and knee abduction moment than the natural and toe-out conditions. Toe-out landing was associated with significantly greater tibial internal rotational angular velocity. CONCLUSIONS: Changing toe direction significantly affects knee kinetics and kinematics during landing. It is important to avoid changing toe direction excessively inward or outward during landing to prevent the increases in knee abduction and tibial internal rotation which might increase the risk of ACL injury. LEVEL OF EVIDENCE: Prognosis, Level IV.
Authors: Timothy E Hewett; Gregory D Myer; Kevin R Ford; Robert S Heidt; Angelo J Colosimo; Scott G McLean; Antonie J van den Bogert; Mark V Paterno; Paul Succop Journal: Am J Sports Med Date: 2005-02-08 Impact factor: 6.202
Authors: Letha Y Griffin; Marjorie J Albohm; Elizabeth A Arendt; Roald Bahr; Bruce D Beynnon; Marlene Demaio; Randall W Dick; Lars Engebretsen; William E Garrett; Jo A Hannafin; Tim E Hewett; Laura J Huston; Mary Lloyd Ireland; Robert J Johnson; Scott Lephart; Bert R Mandelbaum; Barton J Mann; Paul H Marks; Stephen W Marshall; Grethe Myklebust; Frank R Noyes; Christopher Powers; Clarence Shields; Sandra J Shultz; Holly Silvers; James Slauterbeck; Dean C Taylor; Carol C Teitz; Edward M Wojtys; Bing Yu Journal: Am J Sports Med Date: 2006-09 Impact factor: 6.202