The meniscal flounce: a valuable arthroscopic sign

The purpose of this study was to characterise the incidence and significance of the meniscal flounce.

Prospective Cohort Study.

A prospective study of 1088 consecutive knee arthroscopies.

Intact menisci tended to have a flounce of characteristic size and position. The presence of this 'normal' flounce was closely correlated with an intact meniscus (p<0.0001). For the medial meniscus with a small flounce in zone 3 the sensitivity, specificity, and positive predictive value (PPV) for an intact medial meniscus were 68.5%; 92.9%; and 92.1% respectively. Conversely the presence of meniscal pathology correlated closely with either an absent or abnormal flounce (p<0.0001). The absence of a medial flounce had sensitivity, specificity, and PPV for a meniscal tear of 82.8%; 84.9%; and 81.9% respectively.

The findings of this study are useful for arthroscopists especially when there is difficulty visualising all of the posterior half of the meniscus. In this situation the presence of a normal flounce is likely to signify an intact meniscus. However the presence of an abnormal or absent flounce may be the sign of an occult meniscal tear requiring better exposure.