The Stability Analysis of Different Reconstruction Methods After Total Sacrectomy

Selecting six normal complete pelvic specimens to research the biomechanics of different reconstruction methods after total sacrectomy in vitro, this research chose methods of SRR, FRR and ICR to reconstruct the pelvis. Carrying on the progressive load experiment through the universal testing machine in double-leg stance, this research measured the pelvic displacement by the digital image processing technology based on the Imagej software. The biomechanical stability of these four reconstruction methods were analyzed from the performance of the anti-compression in the axial direction, the anti-abduction on the coronal plane and the anti-rotation on the sagittal plane. The pelvis stability after ICR was best, but the manipulation time was long and it was complex. The pelvis stability after BFFR was better than SRR, because its structure was similar to the triangle, whose mechanical stability was better, but the sacral-rod beam structure could prevent well the sinking of the lumbar. The pelvis stability after FRR was the poorest for lacking of the support structure under the lumbar. The pelvis stability had changed after total sacrectomy, so the stability and the continuity between the spine and the pelvic ring were reconstructed necessarily. On the premise of the reconstruction of the bearing bow, the key of the reconstruction after total sacrectomy is to construct the supporting structure underneath the lumbar, use the staggered screw path system to strengthen the pull out strength of the pedicle screw. Meanwhile, it is very necessary to select the biological compound reconstruction of the fibular autograft to enhance the long term curative effect.