Value and limits of arthrography in the study of pathological mediopatellar plicae of the knee; a comparison with arthroscopy

The results from arthroscopy and arthrography were compared in a prospective study of the mediopatellar plicae in 100 knees with internal disorders. With reference to arthroscopy, the sensitivity and specificity of arthrography for the detection of mediopatellar plicae were, respectively, 83.6 and 88.8%. The arthrographic signs of pathological plicae were: a thick plica, thicker than the internal condylar cartilage (sensitivity: 72%; specificity: 84%) and an interposed plica (sensitivity: 85%; specificity: 81.8%). Statistically the arthrographic signs agreed with the arthroscopic signs. The two methods did not differ significantly in their contribution to the diagnosis of pathological plicae.