Anterior Cruciate Ligament Injury Risk Factors by Landing Error Scoring System (LESS) and Muscle Activities during Drop Vertical Jump for Overweight Females

Abstract

PURPOSE The purpose of this study was to investigate the risk factors for anterior cruciate ligament injury using the Landing Error Scoring System (LESS) and muscle activity during the drop vertical jump for overweight females. METHODS The body mass index was 18.5-22.9 kg/㎡ for normal weight females and 23-24.9 kg/㎡ for overweight females among 10 participants aged 20-30 years classified into groups of participants without any injury history and those who were right-footed. An automatic heigh-tweight machine, body composition analyzer, diagnostic imaging, electromyography with the LESS, and muscle activity analysis were used for measurements. The difference in muscle activity between the normal weight and overweight females was evaluated by independent t-test. RESULTS Overweight females had a smaller angle of knee bending during the drop vertical landing, leading to a smaller knee curve angle. In addition, they landed with an unbalanced foot touch on the ground inclined backward, thereby breaking the whole body balance. Overweight females had an incorrect posture compared with normal weight females, with higher LESS points. The muscle activity of the rectus femoris was higher than that of the biceps femoris, indicating a higher load on the muscle. CONCLUSIONS Overweight females take more load on the knee joint and cannot absorb the impact force properly. These results suggest a higher risk of anterior cruciate ligament injury in overweight females.

Keywords

• overweight females
• anterior cruciate ligament
• landing error scoring system
• muscle activity