Loss of job due to being off for W/C

can my employer remove me from my current positon which i am working at for 4 hours a days. prior to my accident i worked 8 hrs a day. if they remove me from that position, don't they have to have a position available for me when I return to work full time, and does that position have to include the same rate of pay? i fell and broke my hip on 2/14/01. my work is basically curret except some followup on some old accounts. I have trained other people in the office to do parts of my job, so we are current on our billing....but some followup is behind. I live in the state of Arkansas. Thank you for your advice.