25yo male sprained his ankle 2-3 weeks ago playing soccer. Ankle radiograph 2 weeks prior showed medial ankle soft tissue swelling, nothing else. I’m wondering why the medial retinaculum is so thick. Edema surrounds the medial retinaculum and it was most likely recently injured with partial stripping from the medial retinaculum. Could this represent acute on chronic injury with the thick retinaculum representing chronic remodeling?
Additionally, there is a thick low signal band traversing from the posterior aspect of the lateral malleolus (kind of blending with the PTFL) and extending posteriorly to the peroneal retinaculum, just superior to the normal CFL. I’m not sure if this is some variant ligament that I’m not aware of or focal thickening of the peroneal retinaculum.
Are these both related to a chronic injury, or some type of underlying fibrotic process? I can’t find any other similar process in the remaining ankle and there is no other injury.
Attached is pdf file with images. Any help appreciated.
Dan A
Thanks everyone for all the quick and great responses. Seems to be consistent agreement that the thick medial band is chronic remodeling and scarring from prior injury, with superimposed acute injury (surrounding edema). I’ll admit that it is much more abundant and thick than I’ve ever seen, but I’m a newbie. Many suggested that the lateral band is either a peroneus quartus, thick CFL, or thick aponeurosis from prior injury. I apologize because the lateral band is hard to completely appreciate on the images I provided, but I’m sure it’s not a peroneus quartus and it is separate from the CFL. I imagine it must be from prior injury, just seems very atypical to me. I also think the CFL has been sprained previously but is not completely torn.