Biomechanical evaluation of lumbosacral reconstruction techniques for spondylolisthesis: an in vitro porcine model.

摘要: Study Design. Biomechanical evaluation of lumbosacral fixation using a porcine model. Objectives. The primary objective the current study was to quantify and compare changes in range motion produced by four different methods surgical stabilization, as well comparing relative effects constructs destructive testing. Background Data. junction continues be difficult region obtain successful spinal arthrodesis is one regions for construct failure. Methods. Twenty-four fresh-frozen spines were used this investigation. Following intact analysis, specimens radically destabilized at randomized into treatment groups based on reconstruction: 1) L7-S1 pedicle screws alone (n = 6); 2) pecicle interbody cage (titanium mesh) 3) iliac 4) pedicle/iliac 6). Nondestructive, multidirectional flexibility analyses included loading fatigue component followed flexural load Lumbosacral peak (millimeters or degrees) ultimate failure (Nm) reconstruction techniques statistically compared one-way analysis variance combined with Fisher's PLSD. Results. Axial compression: There no differences among (P> 0.05). rotation; Iliac screw constructs, without cages, decreased (P < However, reconstructions did not significantly reduce motion. Flexion-extension: cages reduced segmental about junction, which from remaining treatments Lateral bending: afforded less both (with cages). With testing, pullout occurred sacrum, whereas L7-S1/iliac screw, occured proximal adjacent level. Conclusion. levels three (axial rotation, flexion-extension, lateral bending) reconstructions. addition under flexion-extension axial cotation but protect sacral testing did. Based an vitro model, effectively properties junctions; however, are more restrictive (at joint) protective S1 screws.