Study on Viscoelastic Behavior of the Synovial Fluid and Soft Tissue under the Impact Load Condition by High Speed Camera

Generally, Articular cartilage and meniscus in knee joint are superior to impact shock absorption due to cushioning for cartilage. However, at the point of view of the rheology, these soft tissues under the high strain speed impaction loading might lead to operate high viscous resistance in knee joint by the strong visco-elastic characteristics.

In this study, The impact loads of various strain rate were given to porcine knee joint, the visco-elastic behavior of soft tissues in knee joint were measured with the accelerometer as a numerical analysis, and observed macroscopically with the high speed camera.

As a result, measurement data by the accelerometer indicated the function of a shock absorption of knee, however, the high speed camera showed the meniscus and cartilage with the high strain rate have a high viscous deformation resistance. These results suggested the shock absorption mechanism of knee joint under the high impact loading was depend on the excellent elastic characteristics of cancellous bone in tibia and femur.