Higher Boondock 400 step issue for older dog

When I upgraded last year from a 320 to a Boondock 400, it never occurred to me that my pup with have an issue.  She's a little old lady but loves to follow me in and out, up and down.  In the fall after I was nearly done with the camping season I had to take her to the emergency vet for what I thought was abdominal pain.  Many vet visits and lots of $$, it was concluded that she had injured her back.  The consensus was that it was caused by her jumping up and down those steps.  I'm looking into some kind of small, lightweight ramp for her.  I just thought I'd mention this in case someone else has a similar situation.