[The acute knee injury - practical considerations].

The acute knee injury represents one of the most common reasons to visit a general practitioner or an emergency department in a hospital. The initial assessment of an acute knee injury usually is affected by severe swelling, pain and a significant lack of motion. Conventional radiographs in three planes may provide additional information to limit the differential diagnosis. A clinical re-evaluation after five to ten days usually allows proper functional testing and therefore correct diagnosis in the majority of cases can be made. With suspicious clinical findings, MRI may be helpful to evaluate ligamentous, meniscal and cartilaginous structures. Femoro-tibial knee dislocation represents the most harmful acute knee injury and needs to be further evaluated and treated in an adequate medical institution in every suspicious case. Rapid vascular diagnostic with (CT)-angiography is crucial. Behind a multi-ligament injury of the knee a spontaneously reduced dislocation may hide and proper neuro-vascular exam therefore is mandatory in every patient. When fracture, blocking and major instability can be excluded at initial assessment, there is usually no need for any acute surgical intervention and initial conservative treatment may be conducted on an out-patient basis for most of the patients. Priority of surgical treatment depends on the injury pattern and delayed intervention with a pre-habilitative phase may be beneficial for certain pathologies.