Abstract
The purpose of this study was to evaluate landing biomechanics in soccer players following
ACLR during two landing tasks. Eighteen soccer players with an ACLR and 18 sex-matched healthy
control soccer players participated in the study. Planned landing included jumping forward and
landing on the force-plates, whereas unplanned landing included jumping forward to head a
soccer ball and landing on the force-plates. A significant landing×group interaction
was found only for knee flexion angles (p=0.002). Follow-up comparisons showed that
the ACL group landed with greater knee flexion during planned landing compared with unplanned
landing (p<0.001). Significant main effects of landing were found. The unplanned
landing showed reduction in hip flexion (p<0.001), hip extension moments
(p<0.013), knee extension moments (p<0.001), and peak pressure
(p<0.001). A significant main effect for group for gastrocnemius muscle was found
showing that the ACL group landed with reduced gastrocnemius activity (p=0.002).
Unplanned landing showed greater injury predisposing factors compared with planned landing.
The ACL group showed nearly similar landing biomechanics to the control group during both
landing tasks. However, the ACL group used a protective landing strategy by reducing
gastrocnemius activity.
Key words
soccer - landing - ACL reconstruction