Ogilvie J W, Schendel M
Clin Orthop Relat Res. 1986 Feb(203):120-5.
Fusion of L4 and L5 to the sacrum has a high incidence of success. Using conventional methods, nonunion is common when long scoliosis fusions are extended to the sacrum. Three methods of instrumentation for fusing the lumbar spine to the sacrum were compared on a spine simulator test stand. Harrington distraction rods from the sacral ala to L1, Luque rods from L1 to the sacrum, and Harrington compression rods from L1 to the sacrum were tested. The use of a spine instrumentation test stand discounted biologic variation in spinal structure. Sequential loading of each test stand-instrumentation construct in torsion, flexion, extension, and lateral bending gave stiffness constants (Ks) for each test mode. Test values had reproducibility of greater than 94%. Ks illustrates the inability of Harrington distraction rods to the sacrum to resist flexion and torsion, but the ability to resist lateral bend and extension. Harrington compression rod and Luque rod constructs have equivalent stiffness in flexion and torsion. Harrington compression rods efficiently resist extension, and Luque rods resist lateral bending. Harrington distraction rods have limited use in lumbosacral junction fixation other than to correct and resist lateral bending.
L4和L5与骶骨融合的成功率很高。采用传统方法时，当长节段脊柱侧弯融合延伸至骶骨时，不愈合很常见。在脊柱模拟器试验台上比较了三种将腰椎与骶骨融合的器械固定方法。测试了从骶骨翼到L1的哈灵顿撑开棒、从L1到骶骨的鲁克棒以及从L1到骶骨的哈灵顿加压棒。使用脊柱器械固定试验台消除了脊柱结构中的生物变异。对每个试验台器械固定结构依次进行扭转、前屈、后伸和侧方弯曲加载，得出每种测试模式的刚度常数（Ks）。测试值的重现性大于94%。Ks表明，到骶骨的哈灵顿撑开棒无法抵抗前屈和扭转，但能够抵抗侧方弯曲和后伸。哈灵顿加压棒和鲁克棒结构在前屈和扭转方面具有相同的刚度。哈灵顿加压棒能有效抵抗后伸，鲁克棒能抵抗侧方弯曲。除了矫正和抵抗侧方弯曲外，哈灵顿撑开棒在腰骶部固定中的应用有限。
