Presentation
Patellar dislocation?
Patient Data
No knee joint effusion. No Baker's cyst. No intra-articular body. No focus of bone marrow edema and no bone contusions.
High signal of the posterior medial meniscus not reaching the articular surface. No meniscal tear, meniscal extrusion or parameniscal cyst.
Anterior cruciate ligament is intact. Posterior cruciate ligament is intact.
Medial collateral ligament is intact. Lateral collateral ligament complex is intact. No acute posterolateral corner injury.
Quadriceps and patellar tendons are intact. Patellofemoral articular cartilage is preserved. Medial patellofemoral ligament is intact.
Medial and lateral tibiofemoral compartment articular cartilage is intact.
No aggressive focal osseous lesion.
Case Discussion
High signal in the menisci can be a normal finding in adolescents, thought to be related to vascularization. The posterior horn medial meniscus is the most common site. The prevalence may be as high as 80% in 10-year-olds decreasing to 35% in 15-year-olds.