[Complex internal knee lesions--diagnosis, indications and timing].

Ligamentous knee injuries are nowadays more often seen in the office of the family physician, mainly because of an increase in recreational sports injuries. With the help of a questionnaire one can obtain a reliable impression of the injury pattern. The clinical examination is performed in a standardized way, so even in acute ligamentous injuries a correct diagnosis can be obtained at the first examination. The diagnosis of an instability is made with an accurate clinical examination; in case of marginal cooperation of the patient the examination is performed under anesthesia. Depending on the findings, the definitive operation will follow at the same time. In case of a big hemarthrosis we recommend an a.-p. and a lateral X-ray of the knee joint for exclusion of a bony injury before proceeding with the clinical examination. An arthroscopy is indicated in effusions of unclear origin, in the suspicion of meniscal or cartilaginous damage, in a stable knee with hemarthrosis and before definitive stabilization of complex injuries to exclude further damage to other intraarticular structures. Acute ACL ruptures are only operated on in case of bony avulsion fractures, in persons very active in sport and in case of relevant concomitant injuries. Medical collateral injuries without an ACL rupture are usually treated conservatively, except if there is an additional peripheral tear of the meniscus. PCL injuries are seldom operated, except if there is a complex concomitant instability. We aim for an early reconstruction within two weeks after the accident.