Computerized analysis of radiographs in Colles' fractures

Several radiographic parameters correlate with clinical outcome in distal r adius fractures, This study describes a new, computerized routine that auto matically defines the longitudinal axis of the radius, deriving the radial tilt, radial width, and radial height on anteroposterior radiographs of the wrist. The intraobserver and interobserver variability is reported in a se ries of 33 anteroposterior radiographs of the wrist, An edge-finding filter is used to determine accurately the cortices in several lines of each imag e. The midpoints between these two edges are used to determine the best-fit line, thereby defining the longitudinal axis of the bone, The operator mar ks the tip of the radial styloid and the lunate angle of the radius at the distal radioulnar joint. Radial shortening, widening, and loss of angle are calculated. The 33 radiographs were measured twice by two independent obse rvers, and 12 sets of paired readings were analyzed using the two-tailed pa ired t test. The mean difference between readings was reduced to a fraction of degree or millimeter, virtually eliminating the intraobserver and inter observer errors. Thus, the current study shows the computer is a reliable a nd effective instrument for measuring radiographs, The computer-aided syste m of measurements can be extended to prostheses, fractures, and to other or thopaedic measurements.