桡骨远端关节内骨折X线片与CT三维重建影像的准确性对比研究

Comparison of accuracies of fraclxwe assessment between plain X-ray films and 3D CT images in intra-articular distal radius fractures

目的比较X线片与CT三维重建影像描述桡骨远端关节内骨折特征的具体差异。方法利用Paces系统和MIMICS软件分析比较16例桡骨远端关节内骨折的X线片和CT三维重建影像学的特征。结果16例桡骨远端关节内骨折的5个影像学指标，即桡腕关节面塌陷距离、骨折块的个数和移位间隙、骨折是否累及乙状切迹和伸肌腱骨纤维管道，在X线片与CT三维重建影像上的测量结果有较大差异。结论CT三维重建影像能清楚地显示桡骨远端关节内骨折的特征，对骨折分型和治疗方法的选择具有重要的指导意义。

Objective To compare the accuracy of plain X-ray films and reconstructed 3D CT images in assessing characteristics of intra-articular distal radius fractures. Methods X-ray films and reconstructed 3D CT images of 16 cases of intra-articular distal radius fractures were retrospectively analyzed using Paces System and MIMICS software. The parameters that were evaluated included the ability to detect intra-articular step and gap, fracture displacements, the number of articular fragments, stretch of the fracture line to the sigmoid notch and the extensor tendon tunnel. Results The average value for intra-articular step and gap were （0.92 ± 0.75） mm and （0.71 ± 0.87） mm, respectively, on posteroanterior and lateral radiographys. The average value for intra-articular step and gap were （2.58 _± 1.23） mm and （2.89 ± 1.13） mm, respectively, on coronal and sagittal 3D CT images （ P 〈 0.05 ）. The average number of articular fragments was （3.25 -± 1.18） detected by X-ray and （4.68 ± 0.49） detected by 3D CT images （P 〈 0.05 ）. The fracture line was found stretched to the sigmoid notch and the extensor tendon tunnel in 2 cases and 4 cases, respectively, on radiographs. On 3D CT images it was found to be present in 14 cases and 15 cases, respectively （ P 〈 0.05 ）. Conclusion Standard radiographs （anteroposterior and lateral views） are not sufficient to measure anterior displacement nor accurate enough to measure medial displacement of distal radius fractures. Three-dimensional computed tomography improves both the reliability and the accuracy of radiographic characterization of the intra-articular distal radius fracture and influences treatment decisions.