Finite-element study on the function relationship between knee sleeve pressure and body surface displacement and the point position of the leg cross-section

Knee sleeves are one of the most essential protective items for sports enthusiasts. By exerting pressure on the leg during wear, knee sleeves help reduce muscle vibration, providing protection to the human body while effectively enhancing athletic performance. However, most knee sleeve products currently on the market commonly suffer from issues such as imperfect functionality, pressure distribution that does not conform to human body shape characteristics, and an inability to meet the wearer’s needs for exercise and comfort. To improve the functionality and pressure comfort of knee sleeves after wearing, this study established a three-dimensional finite-element model of the human knee joint based on CT images. Geometric models of the “knee sleeve–knee joint” were constructed using MIMICS and Solidworks. Thirty subjects were selected to wear five types of experimental knee sleeves with different structural designs, and pressure tests were conducted to validate the effectiveness of the finite-element model. To further explore the relationship between pressure and human body surface displacement during knee sleeve wear, displacement data from 16 test points on five cross sections of the human knee joint were extracted through finite-element simulation. The results show that the peak pressure was located at the anterior test points where bones protrude, while the peak displacement was located at the posterior test points with thicker soft tissue, exhibiting a nonlinear relationship between the two. To further quantify the functional relationship among pressure, body surface displacement, and leg cross-sectional points, this study established fitting equations of “pressure/displacement versus leg cross-sectional test points” for each cross section of the knee joint, enabling accurate prediction of human body surface displacement based on pressure values. These conclusions provide a theoretical reference and data support for optimizing the balance between functionality and comfort of knee sleeves in accordance with human physiological characteristics.