Hi, thanks for writing to HCM.
A grinding feeling during ankle movements suggests a Fracture
of the involved bones. It might be a small crack for which reason the xrays are inconclusive.
Worsening of pain with time and activity indicates a significant injury
scan of the involved area will clinch the diagnosis about the bony injury as well as any soft tissue
lesion in the surrounding area.
So, consult your treating physician and follow his advice.
Hope this information is helpful. Good day