Author(s): TSENG, P.C., HSIAO, H.Ｗ., LEE, H.J., Institution: NATIONAL TAIWAN NORMAL UNIVERSITY, Country: TAIWAN, Abstract-ID: 1506

INTRODUCTION:
Female athletes have a high incidence of lower limb injuries, with injury risk being significantly greater than in males. Females are 3 to 5 times more likely to sustain unexpected non-contact leg injuries during the season compared to males, making pre-season screening critical. The purpose of this study was to examine potential differences in kinematic parameters, lower limb strength, and dynamic postural stability between healthy and previously injured female athletes during a single-leg drop jump landing. Variables assessed included reactive strength index (RSI), time to stabilization (TTS), and dynamic postural stability index (DPSI) measured during pre-season testing. Detecting differences between healthy and injured athletes on these metrics may help identify limb asymmetries and imbalance that could predispose female athletes to lower extremity injury.
METHODS:
This study enlisted 43 Division I female athletes who had not sustained severe head or lower extremity injuries, nor undergone related surgery in the six months prior. A follow up post-season injury tracking categorized them into a healthy group (n=36) and an injury group (n=7), which included individuals with one anterior cruciate ligament (ACL) tear, three ankle ligament injuries, two quadriceps strains, and one patellar tendinopathy. During the experimental phase, 10 Vicon cameras (200 Hz) captured kinematic parameters, while kinetic data was gathered by Kistler force plates (1000 Hz) during the tasks. Measurements taken included jump height, RSI, impact force, DPSI, and TTS. A one-way ANOVA was conducted to analyze the differences between the healthy group and the injury group, considering both healthy and affected limbs.
RESULTS:
The findings from this study indicate that during the single-leg drop jump, the TTS in the vertical direction (TTS_V) for the injured groups affected side was significantly higher than that for the uninjured side and the healthy group (p<.05). However, no significant differences were observed in jump height, landing impact force, RSI, TTS in anterior-posterior (TTS_AP) and medial-lateral (TTS_ML) directions, or DPSI. Additionally, the valgus angle on the affected side was significantly greater compared to the healthy side and the healthy group (p<.05).
CONCLUSION:
Injuries during jumps are often associated with athletes landing on a single leg. The observed differences in TTS_V suggest that the injury groups affected side requires a longer duration to achieve post-landing stability. Poor dynamic postural stability is acknowledged as a risk factor for ACL injuries among athletes. Furthermore, a larger valgus angle has been identified in previous research as a significant risk factor for injuries, particularly in female athletes. Consequently, the disparities in TTS_V and valgus angle between the injured and healthy sides, as well as between the injured athletes and the healthy cohort of Division I female athletes, may indicate an increased potential for injury.