Advice for Long Plane ride

[chouette]

I have recently been diagnosed with osteoarthritis in both hips, one worse than the other.  While not in constant pain as yet, my hip joint "catches" every time I get up from sitting and has to crack before I can straighten up. This is very painful. (It is also a problem when turning over in bed.)

In a couple of months, I have to take a 7-hour flight, and I am dreading it.  It's an overnight flight, which might make it difficuilt to take frequent standing breaks.  I'm scared that by the time I reach my destination, I will hardly be able to walk.  Does anyone have any suggestions as to the best position to sit or any sitting exercises I might be able to do to help ease the situation.

Also, my ortho surgeon has prescribed high does of Naproxen, which I am reluctant to take because I have high blood pressure and a family history of heart disease, not to mention the fact I am over 70.  Do I have any alternative?

I'd appreciate any advice.
:)