I am physically not able to work, but Hartford wants me to

I have a short term disability claim because I had a spinal fusion. I remained hospitalized for 16 days due to complications and my doctor gave me a ‘release to return to work’ that reads that after reviewing of essential functions of the employees position I determined that that the employee CAN NOT RETURN TO ANY TYPE OF WORK until: 3-6 month of recovery”. Today it is 2 moths and the insurance says they don not think I need to be on disability anymore since I am doing sedentary work and 3 months they do not think is reasonable and that they will forward my claim to some nurse for review. I have a three levels in my lumbar spine fused and this was my fourth back surgery. This is the first surgery that has been with complications and serious set backs, in the past I was able to return much quicker so I never needed to go thru this awful process with short term disability. In any case, I am physically not able to work, I cannot be up for even a half a day at this point, the longest I was able to sit or stand combined has been 1.5 hours or so. I also continue to have a low grade fever that was continuous for 5-6 weeks and is now coming and going but they still do not know from what. Since the insurance said they think I am able to work I now provided them with my doctors release but they said that will not do. Is there anything I can do to fight this? Is short term disability something any attorney will take on?