Injury tolerance of knee joint subjected to dynamic three-point bending

A knee joint injury is one of the most common injuries in car-pedestrian accidents. For the examination of the knee joint injury tolerance and the determination of the absolute range of knee joint injury criteria, we performed dynamic three-point bending tests on the porcine knee joint using the own drop impact test setup. During the test, an impactor (mass: 21 kg) was launched toward the lateral side of the specimen placed on a three-point bending support. The femoral epiphysis was completely fractured when the drop height was 700 mm. Multiple damages to the medial collateral ligament and other soft tissues such as the posterior cruciate ligament were observed when the drop height was 500 mm. Only the medial collateral ligament was damaged when the drop height was 300 mm. No injury was observed when the drop height was 100 mm. The calculation of the maximum bending moment acting at the knee joint showed that the injury criterion range was from 136 to 320 Nm. This range includes the values of injury criterion in previous studies on the human knee joint. Thus, there is hardly any difference between the injury criteria for the porcine and human knee joints. Copyright © 2010 by JSME.