The supine view in double-contrast knee arthrography.

Knee arthrography is a widely used diagnostic procedure, but there is disagreement regarding the relative efficacy of single vs. double-contrast examinations in the evaluation for meniscal tears. In 353 double-contrast knee arthrograms, combining supine positioning with the routinely accepted prone views, there were 222 meniscal tears diagnosed using prone positioning alone, and seven additional tears were found with the added supine maneuver. Even though the knee joint was distended with both contrast material and air, the prone views tended to outline the meniscus in a double-contrast fashion, whereas the supine views provided single positive contrast detail of the same area. Supine views are particularly helpful when an obvious meniscal tear is not fluoroscopically apparent during prone filming.