Barb,

I'd be surprised if you have the ability to adequately grip the handlebars but couldn't use a std. three speed twist or trigger shift.

Anyway, given what you've told us, another option might be Schwinn's 2008 DX cruiser with it's two speed rear hub shifted by a back pedal bump.

http://www.schwinnbike.com/products/...il.php?id=1023

HTH,
TCS