Nice one,
I think you are spot on,
The primary AITFS looks intact in the lower portion, however in the proximal portion it is split down the middle and you can see some fat herniating through the defect,
The AITFS is called a syndesmosis as it is a broad flat collagen sheet and I think you have seen a split involving the proximal part of it and preservation of the distal part.
If you like it is a partial width tear of the AITFS,
There is a concept of the Bassett’s ligament which is the distal end of the AITFS so you could also say this is a tear of the AITFS with preservation of the Bassett’s ligament component.
Steve
Nice one.