If the mass is scar tissue -there are things that can help to dissolve/shrink it
- but is it painful?
is it in the muscle? could she tell from feeling it?

but then if it isn't actually causing a problem or a cause of pain I'd focus on the spinal stuff - as long as it isn't a missed tumor or something serious like that...

You can get a start the SSD filing online at the gov website
http://www.ssa.gov/disability/