Knee and ankle ligaments: magnetic resonance imaging findings of normal anatomy and at injury.

Ligamentous injuries of the lower limb are a common entity sustained during sports activities and military training. Magnetic resonance (MR) imaging of the knee and ankle is playing an increasingly important role in the detection, diagnosis and prognosis of these injuries and their associated complications. MR imaging with its exquisite soft tissue contrast resolution and multiplanar capability is increasingly seen as the modality of choice for evaluating ligamentous injuries of the knee and ankle. Representative knee and ankle MR studies from a tertiary referral hospital are used to illustrate both the normal appearance and typical radiological features of common ligamentous injuries of the knee and ankle. A thorough understanding of the MR appearances of these injuries is crucial to the radiologist and clinicians involved in the management of these patients.