Ankle/Foot

Abstract

MRI is the most complete imaging test for assessing abnormalities of the foot and ankle. It provides excellent soft tissue detail to assess the various tendons and ligaments in the foot and ankle; and it has high sensitivity for the detection of bone marrow abnormalities, such as with talar osteochondral lesions or metatarsal stress fractures. Findings on MRI will often be present much earlier than with other imaging modalities. It is best to have one protocol for imaging the ankle and a second protocol to image the forefoot since many of the structures being studied are small and cannot be adequately studied using a large field of view that encompasses both the ankle and foot. Our “ankle” protocol includes the entire ankle and through the base of the metatarsals distally, whereas our “forefoot” protocol includes all the toes through the base of the metatarsals proximally. When evaluating for Morton’s neuroma or plantar fibroma, intravenous gadolinium contrast is helpful, and when evaluating the stability of osteochondral lesions, MR arthrography can be helpful. We present here the most common entities that you are likely to encounter during MRI imaging of the ankle and foot.