陈旧性齿状突骨折伴寰枢椎脱位患者寰枢椎侧块关节CT影像学分析

Analysis on 3D CT imaging of lateral atlantoaxial joints in patients with old odontoid fracture and atlantoaxial dislocation

中文关键词:  陈旧性齿状突骨折  寰枢椎侧块关节  倾斜角  寰枢椎脱位  CT

英文关键词:Old odontoid fracture  Lateral atlantoaxial joint  Obliquity  Atlantoaxial dislocation  CT

中文摘要:

  【摘要】 目的：观察陈旧性齿状突骨折伴寰枢椎脱位患者寰枢椎侧块关节三维CT影像学特征，探讨其临床意义。方法：回顾性分析2013年6月~2020年4月我院收治的陈旧性齿状突骨折伴寰枢椎脱位患者，按纳入标准共纳入21例作为观察组（A组）；选择年龄段、性别与观察组患者相匹配的21例三维CT未提示枕颈区及颈椎病变或下颈椎曲度异常改变者作为对照组（B组）。在二维CT图像上测量对比两组寰枢椎侧块关节冠、矢状面倾斜角，并将此两指标作为侧块关节形态改变定量评价指标；检验B组观察者间及观察者内信度，测量由两名脊柱外科医师分别独立完成，间隔1周重复测量。统计A组患者骨折病程及寰枢椎侧块关节矢状面倾斜角，使用Pearson相关分析分析骨折病程与侧块关节矢状面倾斜角相关性。根据颈椎过伸位或全麻颅骨牵引下寰枢椎脱位复位情况，将A组患者分为可复型（复位≥50％）与不可复型（复位＜50％）；统计不可复型患者在伴或不伴侧块关节形态改变患者中的占比，分析侧块关节形态改变与寰枢椎脱位复位难易的相关性；比较伴侧块关节形态改变患者与不伴侧块关节形态改变患者寰齿前间隙（ADI）及JOA评分。结果：B组侧块关节冠、矢状面倾斜角测量结果观察者间信度值分别为0.923和0.902，观察者内信度值分别为0.934和0.909。B组42侧侧块关节冠、矢状面倾斜角分别为24.6°±3.9°与14.8°±2.7°；A组41侧（1例伴单侧侧块关节融合无法测量）侧块关节冠状面倾斜角为25.2°±4.1°，两组间比较无统计学差异（P＞0.05），矢状面倾斜角（8.2°±4.9°）小于B组（P＜0.05）。相关分析提示，骨折病程与双侧寰枢椎侧块关节矢状面倾斜角呈负相关（左：r=-0.702，P＜0.01；右：r= -0.605，P＜0.05）。A组患者中12例出现侧块关节塌陷、穹隆状及鱼唇样形态学改变（单侧6例，双侧6例）；经全麻下颅骨牵引评估，可复型为10例，不可复型为11例，伴有侧块关节形态改变的患者中不可复型占比为75％（9/12），无关节形态改变的患者中不可复型占比为22.2％（2/9），两者比较有统计学差异（P＜0.05）。A组中伴侧块关节形态改变患者ADI与JOA评分分别为10.3±1.6mm与9.6±3.2分，与不伴侧块关节形态改变患者（7.2±3.1mm、14.6±3.3分）比较有统计学差异（P＜0.05）。结论：部分陈旧性齿状突骨折伴寰枢椎脱位的患者伴有寰枢椎侧块关节形态学改变，侧块关节形态学的改变与寰枢椎脱位的发生发展及复位难易有一定的相关性；三维CT评估寰枢椎侧块关节形态对手术决策及术中操作具有指导价值。

英文摘要:

  【Abstract】 Objectives: To observe the three-dimensional CT imaging of lateral atlantoaxial joints in patients with old odontoid fracture and atlantoaxial dislocation, and to explore its clinical significance. Methods: Retrospective analysis on the patients with old odontoid fracture and atlantoaxial dislocation admitted from June 2013 to April 2020 in our hospital. 21 patients were included in this study(group A). Twenty-one volunteers matched by age and sex without occipitocervical lesions were selected as control group(group B). The coronal and sagittal inclination angles of atlantoaxial lateral mass joints in group A and group B were measured and compared on two-dimensional CT, which were used as quantitative evaluation indexes of lateral mass joint morphological changes. The measurement was performed by two spinal surgeons independently, and was repeated at an interval of one week. The inter-observer reliability of group B was tested. The course of fracture and sagittal inclination angle of atlantoaxial lateral mass joints were recorded in group A, and Pearson correlation analysis was used to analyze the correlation in between. According to the reduction condition of atlantoaxial dislocation under cervical hyperextension or skull traction under general anesthesia, patients in group A were defined as reducible(reduction≥50%) and irreducible(reduction<50%). The proportion of irreducible patients in group A with or without lateral mass joint morphological changes was calculated to analyze the correlation between the changes of lateral mass joint morphology and the difficulty of atlantoaxial dislocation reduction. The atlantodental interval(ADI) value and JOA score were compared between patients with and without lateral mass joint morphological changes in group A. Results: In group B, the inter-observer reliability was 0.923 and 0.902, and the intra-observer reliability was 0.934 and 0.909. The obliquity in coronal and sagittal plane of 42 sides of lateral atlantoaxial joints in patients in group B were 24.6°±3.9° and 14.8°±2.7°. The obliquity in coronal plane of 41 sides of lateral atlantoaxial joints in patients in group A was 25.2°±4.1°(One case with unilateral lateral mass fusion could not be measured). There was no significant difference of obliquity in coronal plane between group A and group B(P>0.05). The obliquity in sagittal plane of 41 sides of lateral atlantoaxial joints in patients in group A was 8.2°±4.9°, which was less than that of group B(P<0.05). Pearson correlation analysis showed that the duration of fracture was negatively correlated with the sagittal inclination angle of bilateral atlantoaxial mass joints (left: r=-0.702, P<0.01; right: r=-0.605, P<0.05). In group A, 12 patients had lateral mass joint collapse, fornix like and fish lip like morphological changes (unilateral 6 cases, bilateral 6 cases). According to the evaluation of skull traction under general anesthesia, 10 cases were reversible and 11 cases were irreducible. The proportion of irreducible atlantoaxial dislocation was 75%(9/12) in patients with morphological changes of lateral atlantoaxial joint, which was significantly higher than that of patients without morphological changes of lateral atlantoaxial joint 22.2%(2/9)(P<0.05). In group A, the ADI value and JOA score of patients with lateral mass joint morphological change were 10.3±1.6mm and 9.6±3.2, respectively, which were significantly different from those without lateral mass joint morphology change(7.2±3.1mm, 14.6±3.3)(P<0.05). Conclusions: Some patients with old odontoid fracture and atlantoaxial dislocation had morphological changes of atlantoaxial lateral mass joint, and the morphological changes of lateral mass joint were related to the occurrence and development of atlantoaxial dislocation and the reducibility of the atlantoaxial dislocation. For the patients with old odontoid process fracture and atlantoaxial dislocation, three dimensional CT evaluation of atlantoaxial lateral mass joint shape has a certain guiding value for surgical decision-making and intraoperative operation.