Haher T R, Bergman M, O'Brien M, Felmly W T, Choueka J, Welin D, Chow G, Vassiliou A
Department of Orthopaedic Surgery and Rehabilitation Medicine, State University of New York-Health Science Center, Brooklyn.
Spine (Phila Pa 1976). 1991 Aug;16(8 Suppl):S312-8.
Instrumentation designed for stabilization and correction of spinal deformities must limit the amount of motion in flexion and extension. In flexion or extension, the vertebral bodies move about a specific point called the instantaneous axis of rotation. The ability of the implant to limit this motion is a function of its relation to the axis of rotation of the spine. The goal of this study was threefold: 1) to define the instantaneous axis of rotation of the spine in flexion and extension; 2) to study the effect of the loss of the three columns of the spine on the location of the instantaneous axis of rotation; and 3) to determine how the above parameters relate to the choice of anterior or posterior instrumentation. Ten human cadaver spines were subjected to compressive loads in flexion and extension. The columns of the spine were then destroyed in sequence at L3. The instantaneous axis of rotation for each vertebral body was found by the method of Reuleaux, and the effect of the compromise of the columns on the location of the instantaneous axis of rotation was noted. Understanding the exact location of the instantaneous axis of rotation after a specific injury would allow the clinician to objectively choose the best surgical approach and the appropriate instrumentation.
用于脊柱畸形稳定和矫正的器械必须限制屈伸运动的幅度。在屈伸过程中，椎体围绕一个特定点移动，该点称为瞬时旋转轴。植入物限制这种运动的能力取决于其与脊柱旋转轴的关系。本研究的目的有三个：1）确定脊柱在屈伸时的瞬时旋转轴；2）研究脊柱三柱结构缺失对瞬时旋转轴位置的影响；3）确定上述参数与前路或后路器械选择的关系。对10具人类尸体脊柱施加屈伸压缩载荷。然后依次破坏L3节段的脊柱柱。采用勒洛三角形法确定每个椎体的瞬时旋转轴，并记录脊柱柱受损对瞬时旋转轴位置的影响。了解特定损伤后瞬时旋转轴的确切位置将使临床医生能够客观地选择最佳手术入路和合适器械。
