3Okuyama K, Sato K, Abe E, et al. Stability of transpedicle screwing for the osteoportic spine :an in vitro study of the mechanical stability [J]. Spine,1993,18 : 2240-2245.
4Mclain RF,Sparling E,Benson DR. Early failure of shortsegment pedicle instrumentation for throracolumbar fracture: a preliminary report [J ]. J Bone Joint Surg (Am), 1993,75 : 162-167.
5Brantley AG ,Mayfield JK ,Koeneman JB,et al. The effects of pedicle screw fit. An in vitro study[J]. Spine,1994,19 : 1752-1758.
6Polly DW Jr, Orchowski JR, Ellengogen RG. Revision pedicle screws. Bigger,longer shims-- what is best [J].Spine, 1998,23 : 1374-1379.
7Krag MH,Beynnon BD,Pope MH,et al. Depth of insertion of transpedicular vertebral screws into human vertebrae: effect upon screw- vertebra interface strength [J]. J Spinal Disord, 1988,1 : 287- 294.
8Hasegawa K, Takahashi HE, Uehiyama S, et al. An experimental study of a combination method using a pediele screw and laminar hook for the osteoporotic spine [] ]. Spine, 1997,22,958-962.
9Halvorson TL, Kelley LA, Thomas KA, et al. effects of bone mineral density on pedicle screw fixation[J].Spine, 1994,19 : 2415-2420.
10Chiba M, Mclain RF, Yerby SA, et al. Short -- seg-ment pedicle instrumentation. Biomechanical analysis of supplemental hook fixation [J]. Spine, 1996, 21 :288-294.