What Is Injury Biomechanics?

brief introduction

brief introduction

When not bearing weight, the tibia and femur are not in contact with each other, and they are entirely between the meniscus pads. When loading, about 70% of the load-bearing area is on the meniscus, which greatly reduces the stress on the tibial plateau, thereby protecting the cartilage. If the meniscus is removed, the peak pressure on the tibial plateau can rise twice and will cause cartilage degeneration. Under load, the meniscus receives axial stress. Because the anterior and posterior tibia ligaments of the meniscus limit the lateral swelling of the meniscus, the axial stress is converted to its internal hoop stress. If these two ligaments are broken, then Its weight-bearing capacity is completely lost. The cartilage degeneration caused by cutting the anterior and posterior tibia ligaments of the meniscus is similar to the cartilage degeneration caused by the total meniscectomy. It can be inferred that when the meniscus is transected, the load-bearing function of the meniscus is completely lost.

The size of the meniscus resection is proportional to the peak stress on the tibial plateau and proportional to the degeneration of the tibial plateau. This requires us to cut as little as possible when the meniscus is partially removed. The meniscus moves with the tibia, the medial meniscus shifts less than the lateral meniscus, and the meniscus can deform during knee flexion and extension to adapt to the anatomical shape of the knee joint. The coordination of the geometry of the knee joint is maintained, so that the movement of the knee joint is maintained. Meniscectomy does not cause tibia advancement when the anterior cruciate ligament is intact, and it causes greater tibia advancement when the anterior cruciate ligament is broken. In some patients with knee pain, arthroscopic pathology did not reveal any abnormalities, and their symptoms were obvious. After examination, they found that the meniscus had a poor absorption function. In addition, the meniscus also has functions such as lubricating joints. The meniscus can evenly apply joint fluid to the joint surface, which greatly reduces the friction coefficient of the joint.