OBJECTIVETo evaluate the strength of pedicle screw fixation with bone cement in human cadaveric lumbar vertebral bodies by using biomechanical test.

METHODSTwenty-four fresh frozen cadaveric lumbar vertebral bodies were randomly divided into 3 groups, which each group had 8 bodies. The bodies in the first group were drilled only. The bodies in the second group were drilled with tap. The bodies in the third group were drilled and the holes were enlarged by borer. Each vertebral body was drilled in both right and left sides, which one side served as control with the pedicle screws fixation only and another side served as testing side with the pedicle screw fixation with bone cement. The pullout strength was tested on both sides by using borer.

RESULTThere was significant difference of manifestation of pull-strength between the control side and the testing side in all groups (P < 0.001). For the manifestation of pull-strength of testing side in different groups, which had pedicle screw fixation with bone cement, there was no significant difference between the second group and third group, however, the difference between the first group and the second group and between the first group and third group were significant.

CONCLUSIONThe pedicle screws with bone cements could significantly enhance the strength of fixation in cadaveric lumbar compared with pedicle screws only.