A meniscus tear is a structural injury of the inner (medial) or outer (lateral) meniscus in the knee joint. The menisci consist of fibrocartilage, deepen the joint surface and contribute to load distribution and shock absorption.
Acute tears often result from a combination of twisting and axial loading. In older age, degenerative tears also occur. Clinically there may be pain, swelling, a locking sensation and restricted extension. Diagnosis is clinical and by imaging, usually MRI.