Originally Posted by cyclezen

your bar height, relative to seat is already pretty high. going further up is prolly not gonna get you much relief; and will prolly degrade 'handling' on the bike.
maybe try varying your hand position more often.
Straight bars tend to exaggerate the locking of the elbows, if one is not payin attention. Shock forces normally absorbed by the flexing of the arm, drive thru to the shoulder and also down into the wrist and palm. Better to get a good bend in elbow if one can.
Maybe give barends a try. They really make 'life' using a straight bar a lot more bearable for me. I commute every day on my straightbar old MTB and tha barends are DaKine; gives some of the advantages of a drop type bar position. And when I need to be near the brakes for brief sections I just move back to the flat. The barends really allow me to roll and drop my elbows back down and have a nice bend in them - mucho more comfortable and less pressure on the carpal tunnel area.