The Meniscofemoral Ligament Mimicking a Lateral Meniscus Tear

As reported by Sanders et al. 1) , it is challenging for arthroscopic surgeons to differentiate a normal variant of the meniscofemo ral ligament from a tear of the lateral meniscus or loose body formed by an intraarticular avulsed osteochondral or meniscal fragment 2) .Because of its radiological appearance mimicking a pathologic tear of the meniscus or an osteochondral lesion, it is estimated that numerous patients with meniscofemoral ligaments have undergone arthroscopic procedures that was essentially un necessary.We report a rare case of meniscofemoral ligament that was clearly seen on arthroscopy preoperatively and mimicked a lateral meniscal tear, which is also known as a pseudotear of the meniscus. Case ReportA 58yearold male patient presented with left knee lateral pain after a slip down injury a month ago.He had a history of liga mentous injury that occurred 20 years ago, for which no further diagnosis or treatment was done.He had been experiencing mild 'giving way' symptoms since then, but the symptom aggravated after the recent trauma.On the physical examination, we found that the range of motion of the patient's left knee was normal.Medial joint line tenderness was present.The result of the pos terior drawer test was grade 2 positive, and McMurray test was also positiveknee pain in external rotation.Plain Xray showed unremarkable findings.On magnetic resonance imaging (MRI), a longitudinal tear of the medial meniscus (Fig. 1A) and a horizontal tear of the lateral meniscus (Fig. 1B) were shown with highintensity signal on the proton density spectral presaturation inversion recovery coronal image.There was also a slightly highintensity signal shown in the posterior cruciate ligament (PCL), indicating a probable acute partial tear of the ligament or evidence of an old injury.For diagnostic arthroscopy, we made an anterolateral portal for visualization and an anteromedial portal for performing surgery.