Zhang Hongjun, Shao Gaohai, Li Jinghua, et al. Biomechanical study of the spinous screw-hook-laminar static system. [J]. Journal of Chongqing Medical University 41(2):113-117(2016)
Zhang Hongjun, Shao Gaohai, Li Jinghua, et al. Biomechanical study of the spinous screw-hook-laminar static system. [J]. Journal of Chongqing Medical University 41(2):113-117(2016) DOI: 10.13406/j.cnki.cyxb.000654.
Biomechanical study of the spinous screw-hook-laminar static system
Objective:To investigate the biomechanical effects and stability of the spinous screw-hook-laminar static system on fixed and adjacent segment. Methods:Ten fresh adult human cadaveric lumbar spine specimens(L1~S1)were divided into intact group(N)
instable mode group(I)
spinous process screw-hook- laminar static system implantation group(L)
pedicle screw implantation group(P)and Wallis system implantation group(W). Each group had two specimens. In five groups
the stability of lumbar spine and the stress changes of adjacent segment under flexion extension
lateral bending and axial motion were examined repeatedly on the WDW-4100 electronic universal testing machine. Results:Mechanical stability:The stability of the damaged section was notably increased in L group than in I group[vertical displacement:AC(3.17±0.43)mm
P<0.05]. The stability of fixed segments was equally increased in L group than in N group and W group(P >0.05). The stability of L group was inferior to pedicle screw-rod fixation(P)group(P<0.05). Biomechanical effects to adjacent segment disc and zygapophysial joints:under the same mechanical load
there was no significant difference between L group and W group in the stress changes of adjacent segment(vertical displacement:AC(3.12±0.43)mm
Flex(2.72±0.36)mm
Ext(4.32 ±0.36) mm
LB(4.82 ±0.55) mm;lateral displacement:AC(0.67 ±0.01) mm
Flex(0.54 ±0.04) mm
Ext(0.70±0.04)mm
LB(0.78±0.05)mm
P>0.05). L group had low impact on adjacent segment disc and zygapophysial joints than P group [vertical displacement:AC(2.91±0.53)mm