A clinical and radiological study on 68 patients, operated between May 1996 and June 1999. The Omega 21 spinal fixatioin system was employed, using the expandable screw as a sacrum anchor. The objective was to evaluate the efficacy and safety of the aforementioned implant. It was used in 43 cases of discopathy at L5/S1, 12 cases of channel stenosis at S1, 9 cases of spondylitis/listesis, 3 cases of postsurgical fibrosis of the vertebral segment L5/S1 and one case of vertebral fracture. Compared to other conventional sacrum fixation systems, the clinical results are similar, since the good medium to long term stabilisation results are due to the arthrodesis which we systematically perform by means of the biological addition of autologous bone taken from the iliac crest. In the radiological revision there have been no cases of breaking or loosening of the expandable screws. We can conclude that the anchoring strength of the expandable screw does nor diminish, nor does its ability to bear axial load compared to non-expandable screws. In addition it helps to restore the spread the load, like in physiological circumstances. They may be considered of great use in sacrum anchoring.
Ripoll Estela, Guillermo José ; Femenías Rosselló, Juan Miguel ; Rubí Jaume, Miguel. El tornillo expansivo a nivel sacro: Nuestra experiencia. En: Revista española de cirugía osteoarticular, 2003, Volumen 38, Número 213: 25-32
