Fifty-two newborn knees were used to verify the validity of the arthro-TC of double contrast for the diagnosis of normal synovial plicas, aiming at classifying and verifying their quantitative incidence and ethnic distribution. The plica synovialis mediopatellaris was identified in brown (60%), white (40%) and black races (9%) in this study. The incidence in black people was quite low as compared to white and brown people. The most commonly found folds were the plica synovialis infrapatellaris (69%) followed by the plica synovialis suprapatellaris (44%) and plica synovialis mediopatellaris (31%). Plicas were not found in 6% of the knees. The communication of bursa patellares with the articulation of the knee is present at birth in 85% of newborns. Identification of plica synovialis infrapatellaris was difficult because it is covered by abundant fat tissue. Arthro-TC was studied and analyzed by six observers, three radiologists and three orthopedic surgeons. The results showed a medium sensibility of 72% and a medium specificity of 60% for radiologist versus 89% and 61% for orthopedist surgeons, respectively.
Knee; Synovial membrane; Bursa, synovial; Arthrography; Synovial plicae
