The purpose of this biomechanical study was designed to assess construct stabilities of anterior thoracolumbar instrumentation in a calf spine model with an anterior and middle column detect.
Twenty fresh calf spines(L2-L5) were used for the biomechanical tests with an anterior and middle columm defect. L2 and L5 vertebrae were used to attach the loading and base frames Specimens each specimen threc different cases were tested :1)
intact
spine 2) anterior fixation with an interbody graft following total discectomy and endplate excision of L3-L4 disc 3) anterior fixation only without the graft. Four anterior fixators, University Anterior Plating System(UNIV), the Kaneda device,
the
Z-plate, and Texas Scottish Rite Hospital system(TSRH) were used. A PMMA block was inserted into the disc space to simulate the interbody grafting. And a fixation device was implanted with axial compression.
Modern anterior instrumentation for the thoracolumbar spine such as the Kaneda device, TSRH device, Z-plate, and UNIV plate restored the stability in all motions, when an interbody graft has been inserted. The stability of fixation devices
revealed
that
the Kaneda device is the best, particularly in restoring the torsional stability.
The information on the relative stability provided by different instrumentations should help the spine surgeon in choosing the appropriate instrumentation for the operation.
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