Context: The effects of tibial rotation after ACL injury have not yet been well determined.
Objective: To show whether clinical outcomes such as the amount of tibial rotation can affect functional outcomes in normal and ACL deficient knees.
Design: Case control study.
Setting: Research laboratory.
Participants: Twenty normal subjects (Control) and 20 subjects with ACL deficient knees (ACL).
Main outcome measures: Tibial rotation at 30 and 90 degrees of knee flexion was measured using an inclinometer. One-legged hop, crossover hop, figure-of-eight running and 10-m running tests were used and determined the effect(s) of tibial rotation on the outcome of the functional tests.
Results: There were significant between-group differences in internal and external rotation. The relationship between external tibial rotation and the figure-of-eight index was significantly negatively correlated.
Conclusions: The amount of tibial rotation is greater in ACL ruptured knees than in uninjured knees, and these greater amounts of tibial rotation affected the figure-of-eight running index.