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

Abstract

Objective To compare the accuracy of plain X-my fdms 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.Resuts The average value for intm-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 artic~ar 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 sigrnoid 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 sugicient to measure anterior displacement nor accurate enough to measure medial displacement of distal radius fractures.Three-dimensional computed tomography improves both the mhability and the accuracy of radiographic characterization of the intra-articular distal radius fracture and influences treatment decisions. Key words: Radius fracture; Tomography; Three dimensional reconstruction image