• Laurent Balabaud, Emeric Gallard, Wafa Skalli, Bernard Dupas, Robert Roger, François Lavaste, and Jean-Paul Steib.
• Service de Chirurgie Orthopédique, du Rachis et de Traumatologie du Sport, Hôpital Civil de Strasbourg, 1 Place de l'Hôpital, 67091, Strasbourg, France. lbalabaud@wanadoo.fr
• Eur Spine J. 2003 Oct 1; 12 (5): 480486480-6.

AbstractDisadvantages of thoracic posterior implants and developments in rod contouring in situ led to the design of a new spinal implant: the bipedicular spinal fixation device (BSF). The BSF is composed of two bifid hooks linked by a compression transverse connector and inserted into the costo-vertebral and costo-transverse joints. The aim of this biomechanical study was to determine the loading tolerance of the BSF. Three strength tests-a pull-out test, a lateral load-to-failure test and a uniaxial transversal compression test to failure-were performed using six human thoracic spines on an Instron testing device. Specimen evaluation consisted of: bone mineral density (BMD) measurement with the dual-energy X-ray absorptiometry (DEXA) technique, cortical thickness measurements and a morphometric study. The mean values for load-to-failure in the posterior and lateral tests were 324 N and 400 N respectively. The mean value of the uniaxial compression was 988 N. The mean BMD estimated by DEXA was 0.557 g/cm(2). The BSF loading tolerance was compatible with the in situ rod contouring technique requirements when we considered posterior and lateral pull-out tests. The transversal compression test determined the appropriate and efficient BSF tightening force.

26 keywords...

hide…