J Korean Phys Ther.  2020 Oct;32(5):302-306. 10.18857/jkpt.2020.32.5.302.

Comparisons of Vastus Medialis and Vastus Lateralis Muscle Activities according to Different Heights during Drop Landing in Flatfooted Adults

• Chang JS

• KMID: 2520083
• DOI: http://doi.org/10.18857/jkpt.2020.32.5.302

Abstract

Purpose
The purpose of this study was to investigate comparisons of vastus medialis (VMO) and vastus lateralis (VL) muscle activities according to different heights during drop landing in flatfooted adults.
Methods
Fifteen subjects with a flat foot arch and 15 subjects with a normal feet arch were participated. Subjects performed a double limb drop landing task from 20, 40, and 60 cm heights. Surface electromyography was used to measure the muscle activities of the VMO and VL during drop landing.
Results
There were significant differences of muscle activities in the VMO, VL, and the VMO and VL ratio between groups. The electromyography values of VMO, VL, and the VMO and VL ratio in the normal group were significantly greater than in the flat foot group, and muscle activities and the VMO and VL ratio significantly increased with landing heights in the both groups.
Conclusion
Our results indicated that muscle activity patterns of VOM and VL in the flat foot group were lower at heights than in the normal group, so calf tightness was negative effects on balance and gait ability, so assessment of muscle activation patterns in the knee extensors should be considered during exercise and treatment of flat feet.

Keyword

Flat foot; Landing; Vastus medialis; Vastus lateralis