MRI ROAD MAP FOR ANKLE LIGAMENTS IN CHRONIC FOOT PAIN

Abstract

Purpose or Learning Objectives:

To describe the imaging technique, planning and best sequences for MRI ankle. To describe imaging details of normal appearance of ankle ligaments. To describe the imaging findings of tear, degeneration and scarring of ligaments.

Background: MRI can depict ligament injuries and has been used to differentiate ligament tears from other causes of ankle pain, such as fracture, osteochondral injury, or tendon injury. Appropriate treatment planning for ankle injury requires differentiation between the various types of ligament injury. This educational exhibit provides an overview of the MRI features of normal and abnormal ligaments of the ankle. Injured ligaments on MRI may appear disrupted, thickened, heterogeneous, or attenuated in signal intensity, and may be abnormal in contour. PD and PD FATSAT images are often helpful in detecting injury.

Findings: Ankle ligamens are divided into three sections, medial ligaments, lateral ligaments and distal tibiofibular ligaments. The anterior  ligaments have hypointense signal intensity on all sequences, whereas the posterior ligaments are normally of intermediate signal intensity, particularly on PD FATSAT. Torn ligament has fluid signals, disrupted fibers, thinning or thickening and scarred ligament in chronic ankle pain has diffuse thickening and ill definition with low signals on all sequences.

Conclusion: MRI of ankle joint is useful in characterising the ligament tears and PD is the most useful sequence.

Keywords: Musculoskeletal joint, MR, Diagnostic procedure, Athletic injuries