Reliability of images of the acetabular anterior column fracture in fluoro-navigation

Abstract

Objective To study the reliability of images of the acetabnlar anterior column fracture in the fluoro-navigatiou so that a reliable collection of images can be selected for the placement of screws in the operation. Methods Eight artificial pelvic models were used. Eighty K wires were drilled in a retrograde manner into the acetabular anterior columns one by one. For each K wire, 5 images were collected at 5 dif-ferent views. These images were grouped in 7 combinations to judge whether the K wire was in the hip joint or the pelvis. Group A: pelvic AP, inlet and outlet views; Group B: inlet, outlet and obturator oblique views;Group C: pelvic AP, inlet, outlet and obturator oblique views; Group D: pelvic AP, inlet, outlet and out-let-obturator oblique views; Group E: pelvic AP, inlet, obturator oblique and outlet-obturator oblique views;Group F: pelvic AP, outlet, obturator oblique and outlet-obturator oblique views; Group G: inlet, outlet, obturator oblique and outlet-obturator oblique views; The reliability was evaluated through comparison with the actual placement of the K wire. Results When comparison was made according to every single image, the coincidence of the outlet-obturator oblique view was 72.50% (Chi-Square Value = 18.286, P = 0.001).When comparison was made between groups A, B, C and D, the coincidence of the images in group D was 85.00% (Chi-Square Value = 17.891, P = 0.001), When comparison was made between groups C, D, E, F and G, the coincidence of the images in group D was 85.00% (Chi-Sqnare Value = 14. 553; P = 0.006).Conclusion The outlet-obturator oblique view and the collection of images (the AP view, inlet view, outlet view and outlet-obturator oblique view) are highly reliable. Key words: Surgery, computer-assisted; Acetabnlum; Fractures; Tomography, X-ray com-puted; Image