Abstract
<title>Abstract</title> <p>Background Toe orientation during badminton lunge landing may influence lower-extremity biomechanical coordination and knee joint loading, potentially affecting injury risk. This study aimed to examine inter-joint coordination and tissue-level stress responses under different toe orientations during badminton lunge landing using cross-correlation analysis and subject-specific finite element analysis (FEA). Methods Thirty male recreational badminton players (21.70 ± 1.20 years, 175.67 ± 2.53 cm, 65.72 ± 4.08 kg) performed right-leg lunge landings with 20° toe-in orientation (TIO) and toe-out orientation (TOO) in randomized order. Kinematic and kinetic data were collected using three-dimensional motion capture and force platforms. Knee models from eight participants were reconstructed from CT and MRI, and joint forces were applied for FEA. Results Compared with TOO, TIO showed greater ankle dorsiflexion and eversion (p < 0.001) and higher ankle and knee joint reaction forces in the late phase (94–100%, p = 0.045), with increased sagittal-plane center of mass displacement (p = 0.023). TOO demonstrated greater knee abduction angles (p = 0.048–0.007) and higher initial ground reaction force (0–5%, p = 0.048). Coordination differences were observed in ankle motion–knee loading interactions (p = 0.038–0.003). FEA revealed higher peak stress and more concentrated stress distribution in knee tissues under TIO, particularly in the medial compartment. Conclusions Toe orientation markedly modulates kinetic chain coordination and knee stress during badminton lunge landing. TIO increases load concentration across multiple knee structures, whereas TOO facilitates load redistribution and reduces internal tissue stress, suggesting a potential strategy for injury risk reduction.</p>