MRI high-signal intensity in the menisci of asymptomatic children.

We reviewed retrospectively the MRI examinations of 108 knees of 80 children to identify the prevalence of a high signal in the menisci of those without symptoms. There were 51 boys and 29 girls with a mean age of 12.2 years (8 to 15). The prevalence of a high signal within the menisci was 66%, significantly higher than that in an adult group (29%). The prevalence decreased with age: grade-2 and grade-3 changes were observed in 80% of menisci at ten years of age, in 65% at 13 years and in 35% at 15 years. The prevalence of high signals also decreased with increased skeletal maturity at the knee. We emphasise the importance of awareness of the high prevalence of a high signal intensity in the menisci of children, especially in early adolescence.