I have constant awareness of a nagging dull pain in the lower left back but I also have spells of severe pain where I absolutely have to sit down and rest. These happen a few times a week but sometimes several times a day.

The sciatica spells I've had (about 4 of them) that I went to a doctor about (and then to PT) were a constant severe crippling pain, making it impossible to walk without aid.

Since I have MS I'm used to not being able to walk very far but I haven't reached a point where I can't walk at all, and so not being able to stand on account of the sciatica was a big enough problem for me to want to solve it.

The PT involved ultrasound and electrostim.