[Cystic pseudotumors (baker cysts) of the popliteal fossa (author's transl)].

Report on 38 Baker cysts found in 300 knee arthrographies performed for clinically suspected meniscus lesions. In order not to miss these cysts, fluoroscopy and/or X-ray documentation immediately following the instillation of contrast material and air into the knee joint is mandatory, because these contrast agents tend to disappear fairly rapidly, leaving the lesion poorly visible towards the end of the examination. Furthermore, the clinical significance and the therapeutic aspects of Baker cysts are discussed.