Can an employer remove me from my current position on the presumption I could be injured?

Have worked for a company for fourteen years. Have injured myself on 4 occasions. All accidents. Have returned to work as promptly as possible and never been accused of malingering. Recently suffered from tendonitis following an accident. Placed on sixteen days light duty until shoulder returned to normal. Current administrator suggests I step down from my Maintenance position to that of Caregiver in residential wing of building to prevent future injury to myself and costing the company future comp claims? My first injury was as a caregiver when I broke vertabrae and cartlidge in my back in 1997. Was unable to return to work for nearly 3 months. Have had constant pain since that date but my husband refers to me as "Nails" for a reason. I like what I do because it affords me the opportunity to move as I nedd to move and still get the job done. I have been the Maintenance Supervisor for 5 and 1/2 years with no complaints until recently.