Help with case – ankle medial malleolus/navicular facet?

Good evening, fellow OCADers. I’m having some trouble with an ankle case
and I’d like to know if anyone out there can help.

It’s a 40 y-o woman with chronic pain on the medial malleolus. The referrer
says she has a high longitudinal arch (I believe he meant pes cavus), and
on interview she says she had surgery when she was 2 y-o due to
“malformation”, but doesn’t mention which one. I unsuccessfully tried to
reach the orthopedic surgeon for further info.

So here are some images from the MRI and I’m also attaching the whole exam
in a ZIP file (it’s DICOM JPEG so not much of a big file):

[image: AX T1 FS POSTGAD.JPG]
[image: AX T1.JPG]
[image: AX T2FS.JPG]
[image: SAG T1 FS POSTGAD.JPG]
[image: SAG T1.JPG]
[image: SAG T2FS 2.JPG]
[image: SAG T2FS.JPG]
[image: COR T2FS.JPG]
(AX T1 FS POSTGAD, AX T1, AX T2 FS, SAG T1 FS POST GAD, SAG T1, SAG T2 FS
(x2), COR T2 FS)

There’s this bone remodelling between the medial malleolus and a quite
prominent navicular creating some kind of weird articular facet, with lots
of edema and synovitis. I thought maybe the malformation she had surgery
for was pes cavus and she still had some degree of it after surgery
(although I don’t think it shows very well in this non-weightbearing scan),
which caused some degenerative changes, but I’ve seen this between a tilted
talus and the malleolus, not between malleolus and the navicular. And I
never heard about tibio-navicular coalition, so I checked the literature
and found nothing (not sure if it makes sense from an embryological point
of view, maybe not).

She also has peroneal tendinopathy and tear as well as partial atrophy of
medial compartment muscles of the leg (maybe related to pes cavus)

Unfortunately I don’t have prior studies, weightbearing x rays or anything
else (it’s common for patients not to bring those around here, which is a
pity).

Do any of you happen to have seen something like that? Any clues? Help will
be much appreciated! And I promise to post feedback here if I get some
answers, of course

Thanks in advance! Have a nice week!

Guilherme H. Lopes Nunes
Florianópolis, Brazil