Biomechanical analysis of pedicle and lateral mass screws in geriatric human C1 vertebrae and correlation with bone microstructure - L. Rörup; A.L. Kammal; M. Hahn; B. Ondruschka; F.N. von Brackel; T. Rolvien; S. von Kroge; L. Viezens; L.G. Leonhardt (Brain and Spine)