Hmm....Barb and I were posting at the same time!
Remember, I never said she was tactful!

About it being an old injury, if it's still active, then you have a clear etiology--
a "Never Well Since"; and that's what we're always looking for in a case. There's a very good prognosis if we can find this.
Just to give you an example, take someone who comes to a psychiatrist for emotional problems, and there you are writing all their symptoms down, and you're thinking, "Oh, this sounds like Nat-mur, or Aurum!" But, then the patient says, "I've been like this ever since the concussion from the car accident." Now you say hooray! because you've got your remedy!
It could be Arnica, but more likely it's Natrum
Sulph--personality changes after head injury!
Knowing the cause makes all the difference.