Thanks for posting your query.
It seems you have either a bony growth or a cyst
at that site.
Due to prolonged contact with shoes or footwear it has started getting scaly.
There are other differential diagnoses like melanoma
, metastases, lipoma
I think you should get examined by an experienced physician and get investigated and treated if indicated.
Hope I have answered your query.
If you have any questions I will be happy to answer.