I am waiting to be operated on for spinal stenosis. How can I ease the pain in the meantime?

I am 76 yrs old. I take medication for hypertension and cholesterol. Have never had any other complications except that recently I have been diagonised with AMD and have been injected with Avistan twice. I have had sciatica pain since a long time, but recently the pain has became unbearable, so after various tests I have been told that surgery would be the final solution.