Dickson R A
University Department of Orthopaedic Surgery, St James's University Hospital, Leeds, United Kingdom.
Acta Orthop Belg. 1992;58 Suppl 1:21-5.
Idiopathic scoliosis is a complex three-dimensional deformity and in the thoracic region the essential lesion lies in the sagittal plane in the form of an area of inappropriate lordosis. The thoracic kyphosis is normally protected from buckling by being behind the axis of spinal column rotation but when the thoracic lordosis develops it brings the apical region anterior to this axis and thus under compression with resultant buckling failure of the spinal column. The condition of idiopathic thoracic scoliosis is the opposite to idiopathic hyperkyphosis (Scheuermann's disease), the latter being rotationally stable and not moving out of the sagittal plane. The two frequently co-exist in the same spine with thoracic hyperkyphosis above an area of lumbar lordo-scoliosis. There is a spectrum of normal lateral profile and flat backs at the one end are in danger of buckling (lordo-scoliosis) while round backs at the other end of the spectrum are in danger of being defined as Scheuermann's disease. There is no requirement for a specific pathological process. Engineers describe only two ways in which a flexible column can fall into mechanically-angular collapse (kyphosis) and column buckling (lordo-scoliosis). A number of factors favour column buckling (Euler's law) and thus the bigger a deformity the more likely it will be to continue progressing and the taller and more slender the column the more likely it will be to fail and this we see in our patients with idiopathic scoliosis. Not only is lordosis the essential lesion but it is also the primary abnormality which can be demonstrated in children before lateral curvature and rotation develop.
特发性脊柱侧凸是一种复杂的三维畸形，在胸段，主要病变位于矢状面，表现为不当前凸区域的形式。胸椎后凸通常通过位于脊柱旋转轴后方而免受屈曲影响，但当胸椎前凸发展时，它会使顶点区域位于该轴前方，从而受到压缩，导致脊柱屈曲失败。特发性胸段脊柱侧凸的情况与特发性脊柱后凸（休曼病）相反，后者在旋转方面稳定，不会移出矢状面。这两种情况经常在同一脊柱中共存，胸段脊柱后凸位于腰段脊柱侧凸区域上方。正常侧位轮廓存在一个范围，一端的平背有屈曲（脊柱侧凸）的风险，而另一端的圆背有被定义为休曼病的风险。不需要特定的病理过程。工程师们描述了柔性柱陷入机械角塌陷（脊柱后凸）和柱屈曲（脊柱侧凸）的仅两种方式。一些因素有利于柱屈曲（欧拉定律），因此畸形越大，它继续进展的可能性就越大，柱越高越细长，它失败的可能性就越大，这在我们的特发性脊柱侧凸患者中可以看到。不仅前凸是主要病变，而且它也是在儿童出现侧弯和旋转之前就可以表现出来的主要异常。
