Goel Atul, Shah Abhidha
Department of Neurosurgery, King Edward Memorial Hospital and Seth G.S. Medical College, Parel, Mumbai, India.
J Neurosurg Spine. 2009 Mar;10(3):220-7. doi: 10.3171/2008.12.SPINE08499.
The authors investigated the changes in the bone architecture and the characteristics of the neck and craniovertebral region in selected cases of basilar invagination. The reversal in these changes that occurred after decompression and fixation are analyzed. The implications of such an analysis in understanding the pathogenesis of a number of features that are characteristically associated with basilar invagination are evaluated.
One hundred and seventy selected patients with basilar invagination who underwent atlantoaxial joint distraction-fixation surgery at the authors' institution between 1999 and April 2008 were reviewed. The study was prospective after June 2006. A variety of parameters were used for radiological and physical assessments. The evaluation was done on the basis of pre- and postoperative imaging studies and clinical photographs. In the 41 prospective cases, additional direct physical measurements of the neck were performed.
Prior to surgery there were several physical changes such as reduced neck length, torticollis, exaggerated lordosis of the cervical spine, and reduced craniospinal angulation. Other findings included reduced discspace height, significant posterior cervical osteophyte formation, assimilation of atlas (72%), single-level (29%) or multiple-level (3%) cervical fusions, and an increase in the spinal subarachnoid space both above and below the level of maximum neural compression at the tip of the odontoid process. After surgical decompression of the region, there was remarkable recovery in craniovertebral alignments, and an increase in neck length (maximum up to 42 mm) was obvious on physical and radiological examination in 85% of patients. The disc-space height increased and there was a reversal of altered cervical lordosis, craniospinal angulation (maximum up to 36 degrees ), and torticollis.
It appears that a number of physical spinal changes characteristically associated with basilar invagination such as a short neck, exaggerated neck lordosis, torticollis, cervical spondylotic changes and fusions are potentially reversible after decompression and stabilization of the craniovertebral junction.
作者研究了部分基底凹陷病例的骨骼结构变化以及颈部和颅颈区域的特征。分析了减压和固定后这些变化的逆转情况。评估了这种分析对于理解一些与基底凹陷典型相关特征的发病机制的意义。
回顾了1999年至2008年4月在作者所在机构接受寰枢关节撑开固定手术的170例选定的基底凹陷患者。2006年6月后该研究为前瞻性研究。使用多种参数进行放射学和体格评估。评估基于术前和术后的影像学研究及临床照片。在41例前瞻性病例中，还对颈部进行了额外的直接体格测量。
手术前存在多种体格变化，如颈部长度缩短、斜颈、颈椎前凸增大以及颅颈角减小。其他发现包括椎间盘间隙高度降低、颈椎后部明显骨赘形成、寰椎融合（72%）、单节段（29%）或多节段（3%）颈椎融合，以及在齿状突尖端最大神经受压水平上方和下方的脊髓蛛网膜下腔增宽。该区域手术减压后，颅颈排列明显恢复，85%的患者在体格检查和放射学检查中颈部长度明显增加（最大增加42毫米）。椎间盘间隙高度增加，颈椎前凸改变、颅颈角（最大增加36度）和斜颈均出现逆转。
似乎一些与基底凹陷典型相关的脊柱体格变化，如短颈、颈椎前凸增大、斜颈、颈椎病性改变和融合，在颅颈交界区减压和稳定后可能是可逆的。
