A cineradiographic study of the talocrural joint allows a new biomechanical approach of the ankle: MRI with axial and coronal slides were realized: for volume reconstruction in passive movement; scanner was used for axial slides in active movement. There is evidently neither distosis of the bimalleolar grip in dorso- and plantar flexion, nor movement of the lateral malleolus of the fibula, in opposition to the classical description. An anatomical rotation is discussed.