Biomechanical advantage of the index-level pedicle screw in unstable thoracolumbar junction fractures.

摘要: Object Unstable fractures at the thoracolumbar junction often require extended, posterior, segmental pedicular fixation. Some surgeons have reported good clinical outcomes with short-segment constructs if additional pedicle screws are inserted fractured level. The goal of this study was to quantify biomechanical advantage index-level screw in a fracture model. Methods Six human cadaveric T10–L4 specimens were tested. A 3-column injury L-1 simulated, and 4 posterior tested as follows: one-above-one-below (short construct) with/without screws, two-above-two-below (long screws. Pure moments applied quasistatically while 3D motion measured optoelectronically. range (ROM) lax zone across T12–L2 during flexion, extension, left right lateral bending, axial rotation. Results All significantly reduced ROM specimens....