better to stay on limited duty or total disability

[boilerman]

in state of pa

Here is the short version of my case.
I fell of a ladder at work about a year ago.I underwent a cervical fusion at c-3 c-4 and c-5, corpectomy and disksectomy in march of 2010.I also have hereinated disc at L-3,4 and 5 which I am receiving treatment for now. I have been going to physical therapy for the last year.My main problem is as follows. My surgeon said I could go on permanant disability, but in janurary my treating doctor said I could go back to work with restrictions on limited duty at my origin al job. I like my job as a boiler operator and my boss is very accomodiating and basically said whatever I wanted I would get, time off for physical therapy,modified hours etc. He basically fought the administration at the hospital where I work to get me to come back. So now I am back at work the only problem is that it is so strenous just being at work 40 hours a week and going to therapy after work, three times a week. I basically do nothing at work but it just to strenous. Also one of the main reason going back to work was to get medical benefits for my family back. I still get ptd payments because I had a second job that I can not work at yet.
So i guess my main question is was anyone else in a situation like this and what did they do?
Thank you