The Impact of the Novel E‑J Biomechanical Footwear System on Lower Limb Biomechanics in Recreational Female Athletes at High Risk of Non‑Contact ACL Injury: A Feasibility Study
DOI:
https://doi.org/10.37376/ljphp.v3i1.7771Keywords:
ACL injury, Prevention programs, Balance training, Biomechanical footwearAbstract
Anterior Crucial Ligament injury is one of the most severe knee injuries that happens to young athletes who participate in sporting activities that require cutting, pivoting, and sudden deceleration. Prevention programs have proven to lower limb neuromuscular control, which would reflect on dynamic knee stability and functional performance. However, most of those programs have low compliance rates because they require a time commitment and a considerable level of intensity and complexity. The study aims to evaluate the feasibility of performing the intervention on healthy recreational female athletes with the E-J system and to review the current prototype design of the device, according to the user perspective, and finally, to observe any alterations in postural stability. The study was conducted in three phases. Of 15 potential participants, 10 female participants were recruited after being 2D video assessed at the screening phase, as they showed an FPPA exceeding 8.5 degrees while performing a single-leg squat. Participants were assessed using the Y balance test in the pre-intervention phase and after 4 weeks in the post-intervention phase. Compliance rate, Y-balance test outcomes of each limb length, reach for the right and left lower limbs in three directions each (Anterior, Posteromedial, Posterolateral). Results showed a significant (p-value < 0.05) increase in limb length of reach, along with a compliance rate of 89%. The outcomes suggest that performing an intervention with the E-J system is safe and feasible. In addition, the E-J system demonstrated that it may have potential for improving lower limb postural stability.
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Copyright (c) 2026 Ihab El-Zein, Marwan Abdelaziz, Richard Jones, Abdulla Alrahoomi
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