Why does the patellar tendon tear?
Tendons are the structures of the musculoskeletal system that transmit the force of the muscles, like cords, they function as lever arms that make the joints move. The patellar tendon is one of the most powerful in the human body. It is part of the powerful extensor mechanism of the knee, along with the quadriceps, quadriceps tendon and patella. The tendon is a set of collagen fibers whose function is to transmit the force of the quadriceps muscles to the distal insertion point in the tibia bone to extend the knee. It is essential to stand upright, jump, run or walk. These structures support loads several times greater than body weight during sports or efforts made in activities of daily life. Patellar tendon rupture is a rare injury which generally occurs in the final phase of chronic tendinopathy, but it can also be an acute injury, due to direct or indirect trauma. The injury occurs after the violent contraction of the quadriceps muscle, for example, when hitting a ball or jumping, in any of its phases. The factors that predispose the injury are generally associated with the type of activity performed by the athlete and their anatomical characteristics that could contribute to the development of chronic patellar tendinopathy. In acute breaks, the most commonly associated factors are overweight and jumping sports, running, contact, weight lifting, excessive bodybuilding or the repeated use of anabolic steroids, which weaken the tendon. Many of the athletes who suffered this serious injury did not have previous tendon discomfort, although this does not mean that there could not be a previous tendon degeneration. Many athletes have finished their sports careers or suffered significant sequelae from the rupture of this tendon, most of them having suffered degenerative tendinopathy, which is caused by overloading the tendon and its poor biological capacity to regenerate. This forces most of them to receive treatments that allow them to alleviate the symptoms to remain active and fulfill their commitments to sports competitions. One of the most widespread cases happened 20 years ago, Ronaldo Nazario, in a cup final, broke the patellar tendon in his right knee and it took a year and a half to reappear. Now we know the case of the diver Germn Snchez, who unfortunately will not be able to attend Tokyo. We hope that he makes a full recovery soon so that he can continue to win medals. _  Ignacio Cardona  .