Quantitative Analysis of Quadriceps Forces in Adolescent Females during Running with Infrapatellar Straps.

Osgood-Schlatter disease (OSD) is caused by high, repetitive, and continuous traction exerted by the quadriceps on the tibial tuberosity, primarily occurring in adolescents. Infrapatellar straps are commonly recommended for its prevention and treatment, yet their impact on quadriceps forces in adolescents remains unstudied. Furthermore, current research on OSD predominantly focuses on adolescent males, with limited attention to adolescent females, despite similar incidence rates in both groups. This study aimed to quantify the quadriceps forces during running, both with and without infrapatellar straps, in adolescent females. Kinematic data, ground reaction forces, and electromyography (EMG) data of knee muscles from 16 adolescent females were recorded as they ran at self-selected speeds with and without infrapatellar straps. OpenSim was employed to estimate quadriceps activations and forces, from which accumulated forces were derived. The simulation's reliability was validated by calculating the correlation between muscle activations obtained from OpenSim and EMG data, which revealed a strong correlation. Wearing infrapatellar straps during running decreased the peak and accumulated forces of the quadriceps (p < 0.001, and p < 0.001, respectively). The significant reduction in accumulated forces was associated with decreased vastus muscle forces during the stance phase (p = 0.002, p = 0.003, and p = 0.016 for vastus lateralis, vastus medialis, and vastus intermedius, respectively). The use of infrapatellar straps had limited effect on the rectus femoris muscle forces. The reliability of the simulation was validated through EMG data. Wearing infrapatellar straps may reduce the load exerted on the tibial tuberosity by decreasing vastus muscle forces during the stance phase. Adolescents aiming to reduce excessive rectus femoris muscle forces due to a shortened or tight rectus femoris, which may contribute to the occurrence of OSD, might experience limited benefits from wearing infrapatellar straps.