An episode of ‘giving way’ at the ankle is described as excessive inversion of the rearfoot that does not result in an acute ankle sprain and is a unique feature associated with chronic ankle instability (CAI). Limited data currently exists describing the preparatory movement patterns and those that occur during an episode of ‘giving way. Therefore, this case report describes the movement patterns and the forces generated during an unintentional ‘giving way’ captured while an individual with unilateral CAI was performing a single-leg landing task in a research laboratory. The participant completed five single-leg landing trials for both limbs. 3D lower extremity kinematics and kinetics for the sagittal and frontal plane were extracted from 200 ms before and after initial contact (IC). Relative to the affected and un-affected single-leg landing trials, the ‘giving way’ episode was characterized by an increase in plantarflexion and hip extension moments before and after IC. The plantarflexion deviation dissipated (50 ms post-IC) and was followed by excessive ankle inversion. The ankle began to plantarflex again (150 ms post-IC) and the knee extended (50 ms post-IC) and adducted (100 ms post-IC). As a result, the ankle inversion angle plateaued at 150 ms post-IC. Furthermore, large sagittal plane internal joint moments were observed. In the frontal plane, the ‘giving way’ trial generated a large inversion joint moment which was counteracted by a large internal eversion joint moment. The observed plantarflexion and knee extension and adduction after initial contact likely contributed to preventing the ankle from continuing to invert and avoid an ankle sprain.
|Number of pages||6|
|Journal||Journal of Biomechanics|
|State||Published - Jun 11 2019|
Bibliographical noteFunding Information:
This research was funded by the 2018 Southeast Athletic Trainers Association Research Grant.
© 2019 Elsevier Ltd
- Ankle sprain
ASJC Scopus subject areas
- Biomedical Engineering
- Orthopedics and Sports Medicine