Abstract:

Objective　To investigate the reliability and clinical value of anatomic tilt x-ray of wrist joint evaluating the position of the distal radius screws.　Methods　31 patients, in whom the distal radius screws were suspected penetrating into the joint in standard X-ray films, received further evaluation in CT scans and  anatomic tilt x-ray of wrist joint (abbreviated ATX). Two observers were selected to judge independently the screw position from ATX, the sensitivity, specificity and predictive value, as well as the consistency of ATX were calculated compared with CT scans. 67 patients, in whom the screws were suspected penetrating into the joint in standard X-ray images, judged by ATX were: no penetration in 39 cases and penetration in 28 cases. Removal of penetrating screws: replacing screws during the operation or early removal postoperatively after healing of fractures.　Results　The sensitivity of ATX was 88.24%~94.12%,the specificity was 87.50%～106.25%,and the predictive value was 87.50%~100.00%;the intra-observer Kappa coefficient was 0.81～0.94, with a high reliability, the inter-observer Kappa coefficient was 0.87 each, with a high  reproducibility. The patients were followed up for 16 to 30 months. At the last follow-up, the wrist joint function (Sarmiento’s criterion): excellent in 14 cases, good 19 in cases, fair in 5 cases and poor in 1 case in the no penetrating group, whereas the efficacy was excellent in 10 cases, good in 13 cases, fair in 4 cases and poor in 1 case in the penetrating group. There was no significant difference (P>0.05).　Conclusions　Evaluation of the position of the distal radius screws with ATX is simple, practical and reliable.

Key words: X-ray imaging, Distal radius fractures, Screw position, Anatomical tilt X-ray