Hello In April 2015 My Femoral Nerve In My Leg

Hello in April 2015 my femoral nerve in my leg was severely damaged while hooking me up to the heart and lung machine for what turned out to be a 12 hr surgery to repair my TAAA. Been doing PT mostly stretches for my post lateral thoracic incision and to calm down the hypo sensitive in leg and back.
46/F
1?) I feel as if my progress is going backwards .. Lately my leg and knee have become extremely weak.
I have lots of atrophy.
2?) Dr has me off work till January 2016
He said if I'm not better by then I need to look into disability. Office work
Why does my doctor have me off of work for so long is it due to the risk of me falling or because of so much nerve damage and the pain I'm in? Cant sit or stand for long. Or has he seen this before and I will not recover fully?