Application of three-dimensional CT reconstruction in postoperative evaluation of ankle fracture

Abstract

Objective To analyze the application of three-dimensional CT reconstruction in postoperative evaluation of ankle fracture.Methods The data of 168 patients with ankle fracture from May 2009 to June 2012 were analyzed.According to Lauge-Hansen classification,there were 85 cases of supination-external rotation (SER) pattern,32 supination-adduction (SAD) pattern,27 pronation-external rotation (PER) pattern and 24 pronation-abduction (PAB) pattern.They were all closed fractures and conventional operations were performed within 2 weeks.Postoperative antero-posterior and lateral radiographs and 16-slice spiral CT scan images were studied to evaluate fracture reduction and implant placement using the volume rendering mode and multiplanar reconstruction mode.The CT scans were then compared with radiographs.Results Radiographs revealed non-anatomic reduction in 6,1,2 and 2 patients in groups SER,SAD,PER and PAB respectively,while CT scan images did in 36,12,8 and 3 patients in the 4 groups respectively.Significant differences between CT scans and radiographs were observed in groups SER,SAD and PER,as well as in the overall evaluation (P ＜ 0.05).As for implant placement,radiographs revealed poor implantation in 2,1,0 and 0 patients in groups SER,SAD,PER and PAB respectively,while CT scan images did in 8,8,3 and 4 patients in the 4 groups respectively.Significant differences between CT scans and radiographs were observed in groups SER and SAD,as well as in the overall evaluation (P ＜ 0.05).Conclusion Three-dimensional CT reconstruction may be more reliable than radiographs in the postoperative evaluation of reduction and implant placement for ankle fractures. Key words: Ankle; Fractures, bone; Fracture fixation, internal; Imaging, three-dimensional