PURPOSE: To determine the prevalence of a meniscal flounce, the magnetic resonance (MR) imaging characteristics, and whether the flounce is associated with a meniscal tear. MATERIALS AND METHODS: Knee MR images obtained in 3,159 examinations over 2 years were prospectively evaluated. Ten adult patients (six with true flounces, four with flouncelike folds associated with meniscal tears) with an S-shaped fold in the free edge of a meniscus on sagittal images were included. Five underwent arthroscopic surgery. RESULTS: The prevalence of a flounce was 0.2% (six of 3,159 examinations). Five occurred in the medial meniscus (MM) and one occurred in the lateral meniscus (LM). All appeared truncated in the coronal plane. Four meniscal tears also demonstrated flouncelike folds. Three were confirmed with surgery and one was confirmed with clinical findings. Of the 3,159 MR examinations, 1,151 demonstrated an MM tear, 832 an LM tear, 542 MM degeneration, and 270 LM degeneration. CONCLUSION: A meniscal flounce is a fold that occurs in the absence of a tear, and presence of it does not increase the prevalence of a tear. Because tears may result in a flouncelike fold, a flounce should be considered a normal variant only in the absence of other indications of a meniscal tear.
PURPOSE: To determine the prevalence of a meniscal flounce, the magnetic resonance (MR) imaging characteristics, and whether the flounce is associated with a meniscal tear. MATERIALS AND METHODS: Knee MR images obtained in 3,159 examinations over 2 years were prospectively evaluated. Ten adult patients (six with true flounces, four with flouncelike folds associated with meniscal tears) with an S-shaped fold in the free edge of a meniscus on sagittal images were included. Five underwent arthroscopic surgery. RESULTS: The prevalence of a flounce was 0.2% (six of 3,159 examinations). Five occurred in the medial meniscus (MM) and one occurred in the lateral meniscus (LM). All appeared truncated in the coronal plane. Four meniscal tears also demonstrated flouncelike folds. Three were confirmed with surgery and one was confirmed with clinical findings. Of the 3,159 MR examinations, 1,151 demonstrated an MM tear, 832 an LM tear, 542 MM degeneration, and 270 LM degeneration. CONCLUSION: A meniscal flounce is a fold that occurs in the absence of a tear, and presence of it does not increase the prevalence of a tear. Because tears may result in a flouncelike fold, a flounce should be considered a normal variant only in the absence of other indications of a meniscal tear.
Authors: Hye Jin Yoo; Kyung Nam Ryu; Ji Seon Park; Wook Jin; So Young Park; Hye Jin Kang; Hyun Soo Kim; Gene Hyuk Kwon Journal: Taehan Yongsang Uihakhoe Chi Date: 2021-10-18