伴寰枢椎脱位颅底凹陷症患者后路减压失败的再手术治疗

Revision surgery for basilar invagination associated with atlas-axis dislocation after failed magnum foramen decompression

中文关键词:  颅底凹陷症  寰枢椎脱位  枕大孔减压术  经口咽前路复位钢板

英文关键词:Basilar invagination  Atlas-axis dislocation  Magnum foramen decompression  Transoral anterior reduction plate

中文摘要:

  【摘要】 目的：探讨伴有寰枢椎脱位的颅底凹陷症患者后路减压失败的再手术对策。方法：2006年2月~2010年10月我院收治９例在外院接受后颅窝减压手术术后症状加重的伴寰枢椎脱位颅底凹陷症患者，入院时患者均有站立或行走不稳，肢体麻木、无力，JOA评分7~11分，平均7.8±2.1分，影像学检查显示枕骨大孔周围大部分骨质均被咬除，且均有明显的寰枢椎脱位，枢椎齿状突向上脱入枕骨内并压迫脑干和延髓，脑干脊髓角105°~138°，平均125°±11°。均采用经口前路齿状突复位、钢板内固定、植骨治疗。随访患者神经功能改善情况，术后3个月及末次随访时对患者进行JOA评分，计算脊髓神经功能改善率；在颈椎MRI片上测量脑干脊髓角，并与术前比较。结果：手术均顺利完成，未出现硬脊膜破裂、切口感染等并发症。随访10~26个月，平均14个月，9例患者神经功能均有不同程度的改善，术后3个月时JOA评分为13.7±1.8分，改善率为64.1%；脑干脊髓角改善至148°±15°。末次随访时JOA评分为14.4±2.1分，改善率为71.7%；脑干脊髓角维持良好。8例患者在术后6个月左右复查CT均显示植骨达到骨性融合；1例患者随访期间头部外伤致内固定松动，再次翻修，随访10个月植骨获得骨性融合。结论：后颅窝减压术不能解决寰枢椎脱位造成的脑干前方压迫问题，不适合治疗伴有寰枢椎脱位的颅底凹陷症，经口前路齿状突复位钢板内固定手术可以将寰枢椎脱位有效复位，恢复枕颈交界区域的有效椎管直径，纠正脑干脊髓角度，可以作为后颅窝减压失败后的补救手术。

英文摘要:

  【Abstract】 Objectives: To investigate the revision surgery for basilar invagination associated with atlas-axis dislocation after failed magnum foramen decompression. Methods: From February 2006 to October 2010, 9 cases suffering from basilar invagination associated with atlas-axis dislocation were included in this series. All cases underwent posterior magnum foramen decompression in other hospitals prior to admission into our institute, and all had neurofunction deteriorated. All patients presented with difficulty in standing or walking and limb numb or weakness. The preoperative JOA score was 7-11(average, 7.8±2.1). Bone defect due to decompression around the magnum foramen was evidenced in the image, and all cases had atlas-axis dislocation with the brain stem compressed by the odontoid process of axis. The brain stem- medulla oblongata angle was 105°-138°(average, 125±11°). Revision surgery of transoral anterior reduction and fixation with transoral anterior reduction plate（TARP） was performed. The JOA score was used to evaluate the neurofucntion, and the brain stem-spinal angle was measured for evaluating the decompression. Results： All cases underwent the revision surgery successfully with no complication such as dura rupture, infection et al, and all 9 cases were followed up for 10-26 months(mean, 14 months) and all had neurofunction improved with different extent. The JOA scores improved from 7.8±2.1 to 13.7±1.8 three months after revision surgery with the improvement rate of 64.1%. The stem-spinal angles improved from 125°±11° to 148°±15° three months after revision surgery. At final follow-up, the average JOA score was 14.4±2.1 with improvement rate of 71.7%, and the brain stem-medulla oblongata angle maintained well. 8 cases had bony union in CT scan 6 months after revision surgery. 1 patient was subjected to the second revision due to instrument failure after an injury to the head,and got bony fusion 10 months later. Conclusions: Posterior magnum foramen decompression can not decompress the ventral side of brain stem， which cannot be used for basilar invagination complicated with atlas-axis dislocation, while anterior transoral reduction and instrumentation can manage this effectively and can be used as a salvation to the failed posterior magnum foramen decompression.