In this paper, the aim is to describe knee injuries occurring as a result of sports and recreational activities. In order to better understand the injuries, anatomy of the knee is firstly described. Three bones are connected in the knee: femur, tibia and patel. For joint stability, ligaments are most important, while the meniscus correctly distribute pressure on the joint and reduce vibrations caused by movement. The muscles make the movement of the knee joint, and the most important knee movements are flexion and extension. Through further analysis, internal and external causes that significantly affect the risk of injuries are described. The main internal causes are the biological and anatomical nature of the individual, the differences between the sexes, the degree of adolescent development, and the quality of the training. The main external causes that increase the risk of injuries are the environment and the equipment that an individual uses during recreation or sport. In addition, characteristic knee injuries that occur during sporting movements were described. Tear of the anterior cruciate ligament is the most common consequence of internal rotation of the tibia in combination with valgus rotation or hyperextension of the knee. The posterior cruciate ligament is most often injured due to the posteriorly directed force on the tibia. The collapse of the collateral ligaments occurs due to the sudden force acting on the knee of the lateral or medial side and causing valgus or varus rotation. Meniscus injuries occur after rotation while the knee is in flexion or extension. Anterior cruciate ligament injury in alpine skiing caused by the Slip-catch mechanism is taken for more detailed biomechanical analysis. Before injury, the skier loses balance and loses contact with the surface. In the desire to reestablish the contact, the skier extends the knee so that the ski runs away from the center of the body mass. When a ski tail suddenly establishes contact with the surface, a powerful reactive force on the tail is produced, causing the internal rotation of the tibia and valgus rotation. The consequence is the collapse of the anterior cruciate ligament in the knee. The analysis shows that the main causes of injury are extended knee, parabolic form of modern carving skis and ski bindings. As a possible solution to the problem, the last chapter describes the concept of the mechatronic ski system. The positions of the moment sensors, the position sensors and the angle sensors are displayed, and based on the previous analysis, a regulation algorithm was created.