Synonyms
Anterior cruciate ligament rupture, ACL rupture, anterior cruciate ligament lesion
Definition
A torn anterior cruciate ligament in a child is, as in adults, a complete or, in the case of a tear, an incomplete interruption of the continuity of the anterior cruciate ligament (ligamentum cruciatum anterius) in the knee joint. The ligaments of the human body consist of taut connective tissue arranged into firm fibers. By nature, these ligaments are very stable and suitable for withstanding high loads.
When comparing the anatomical structures of the knee joint in children with those of adults, there are no differences in the structure except for the size. Children are therefore almost as frequently affected by injuries to the knee joint as, for example, torn anterior cruciate ligaments. The anterior cruciate ligament is a part of the ligamentous apparatus that secures the knee joint.
It is located inside the joint capsule and, together with the posterior cruciate ligament (ligamentum cruciatum posterius) and the posterior meniscus ligament (ligamentum meniscofemorale posterius), forms the inner ligaments of the joint. The ligament also connects the femur with the tibia. In addition to the inner ligaments, there are also the outer (collateral) ligaments, namely the outer and inner collateral ligaments.
As the name suggests, these fibrous structures are located on the outside of the joint and outside the joint capsule. While the outer collateral ligament connects thigh (femur) and fibula, the inner collateral ligament connects thigh (femur) and tibia. The inner ligaments, and among these the cruciate ligaments, are primarily responsible for the cohesion and stability of the joint body, as the femur would otherwise slip out of the flat socket of the tibia.
Furthermore, the cruciate ligaments restrict mobility in the knee joint and thus provide even more stability. When the joint is moved, the ligaments wrap around each other when turned inwards and unwind when turned outwards. In addition to mechanical functions, the internal ligaments also contribute to sensory function (proprioception) by detecting the position of the joint in space through specialized nerve endings and transmitting this information to the brain via the spinal cord.
Due to their position, the cruciate ligaments, especially the anterior cruciate ligament, are quite susceptible to injuries such as overstretching or tears (ruptures). Torn ligaments in the knee joint are among the most common injuries, but are usually easy to treat. However, treatment is often more difficult for children than for adults.
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