[Registration of fibular movements in vivo in relation to the tibia at the level of the ankle joint].

Fibular movements in relation to the tibia are known on extension and dorsiflexion of the ankle-joint and have been proved by experiences on cadaveric preparates using outstanding points of relation. To registrate fibular movements in vivo a special trigonometric system has been developed permitting calculation of definite movement in frontal and sagittal plane as well as a rotation around axis. Twelve healthy volunteers were examined in this way during extension and dorsiflexion of the ankle, with and without weight-bearing. The results showed that we should not consider isolated fibular movement but analyse simultaneous complexity of movements in a graphic comparison. Under these conditions we observe a very high significance of fibular movements depending each of other. The emphasis can be designed in a field covering all the points reached by fibular movement in frontal and sagittal plane of the twelve healthy volunteers during movement of the ankle; it shows that the fibula functions like a guide-stick for ankle movement. Reflecting on the designed fields of healthy persons, some patients with posttraumatic pathological alterations of the ankle-joint have been analysed.