[A foreign body in the knee joint--a very rare injury in children].

Cause of uncertain knee-complaints in children can be foreign bodies which penetrated unnoticed the joint cavity. Here we report an unusual injury of this kind. A glass-foreign body intruded the knee joint in childhood. Complaints occurred for the first time in adult age. The diagnostic and therapeutic measures in such injuries are shown. At removal of the foreign body tetanus immunisation is necessary.