What was the knee damage? 
My son dislocated his knee cap half a dozen times then eventually surgery.  Not sure what all they did but… about a week of hell then manageable for him. 6mos out he was back to no limitations, although he was nervous much longer. His surgery was considered elective and outpatient. 
You’re looking like a whole nother level with immobility. So sorry. Don’t they give a pain drip anymore? Just press a button?? C’mon nurses, help this man!