MR imaging of the ankle: normal and abnormal findings in the medial collateral ligament

The medial collateral ligament (MCL) of the ankle, also known as the deltoid ligament, attaches the medial malleolus to the tarsus. There are almost as many different descriptions of the components of the MCL as there are people describing them. Differences exist as to whether it has superficial and deep components, which ligaments are superficial and which are deep, the attachment sites of the component ligaments, and even the number and names of component ligaments [1]. Additionally, evaluation of the MCL on MR images has been largely ignored. This pictorial essay illustrates the normal component ligaments of the MCL, as well as injuries to each of these components, as seen on three-dimensional Fourier transform (3DFT) gradient-recalled echo (GRE) MR images in 81 patients (86 ankles).