PDF(Pubmed)
Abstract：
In forensic commingled contexts, when the disarticulation occurs uniquely at the atlantoaxial joint, the correct match of atlas and axis may lead to the desirable assembly of the entire body. Notwithstanding the importance of this joint in such scenarios, no study has so far explored three-dimensional (3D) methodologies to match these two adjoining bones. In the present study, we investigated the potential of re-associating atlas and axis through 3D-3D superimposition by testing their articular surfaces congruency in terms of point-to-point distance (Root Mean Square, RMS). We analysed vertebrae either from the same individual (match) and from different individuals (mismatch). The RMS distance values were assessed for both groups (matches and mismatches) and a threshold value was determined to discriminate matches with a sensitivity of 100%. The atlas and the corresponding axis from 41 documented skeletons (18 males and 23 females), in addition to unpaired elements (the atlas or the axis) from 5 individuals, were superimposed, resulting in 41 matches and 1851 mismatches (joining and non-joining elements). No sex-related significant differences were found in matches and mismatches (p = 0.270 and p = 0.210, respectively), allowing to pool together the two sexes in each group. RMS values ranged between 0.41 to 0.77 mm for matches and between 0.37 and 2.18 mm for mismatches. Significant differences were found comparing the two groups (p < 0.001) and the highest RMS of matches (0.77 mm) was used as the discriminative value that provided a sensitivity of 100% and a specificity of 41%. In conclusion, the 3D-3D superimposition of the atlanto-axial articular facets cannot be considered as a re-association method per se, but rather as a screening one. However, further research on the validation of the 3D approach and on its application to other joints might provide clues to the complex topic of the reassociation of crucial adjoining bones.
摘要：
在法医混合的情况下，当关节脱离发生在寰枢关节时，地图集和轴的正确匹配可能导致整个身体的理想组装。尽管这种联合在这种情况下很重要，到目前为止，还没有研究探索三维（3D）方法来匹配这两个相邻的骨骼。在本研究中,我们研究了通过3D-3D叠加重新关联图集和轴的潜力，通过测试它们的关节表面一致性在点对点距离方面(均方根，RMS）。我们分析了来自同一个体（匹配）和来自不同个体（不匹配）的椎骨。评估两组(匹配和不匹配)的RMS距离值,并确定阈值以区分具有100%灵敏度的匹配。来自41个有记录的骨骼（18个男性和23个女性）的地图集和相应的轴，除了来自5个人的未配对元素(地图集或轴)，被叠加，导致41个匹配和1851个不匹配（连接和非连接元素）。在匹配和错配中没有发现性别相关的显著差异(分别为p=0.270和p=0.210),允许将每组中的两种性别聚集在一起。匹配的RMS值在0.41至0.77mm之间，不匹配的RMS值在0.37至2.18mm之间。比较两组发现了显着差异（p<0.001），匹配的最高RMS（0.77mm）用作区分值，提供了100％的灵敏度和41％的特异性。总之,寰枢关节面的3D-3D叠加本身不能被认为是一种重新关联方法，而是作为一个筛选。然而,对3D方法的验证及其在其他关节中的应用的进一步研究可能会为关键相邻骨骼的重新关联这一复杂主题提供线索。
