What Causes Increasing Edema And Pain After Successful Back Surgery?

hELLO I HAD SIGNIFICANT BACK SURGERY (GOING THROUGH THE BACK AND FRONT AND HAD DISKS PLACED AREAS L.. -2 TO S1 TO CORRECT MY EXTREME SCOILIOSIS. wHILE IT IS CONSIDERED SUCCCESSFUL (I AM STRAIGHT) THE LAST COUPLE OF WEEKS I HAVE DEVELOPED INCREASING EDEMA AND PAIN. SURGERY TOOK 11 HOURS. THE EDEMA HAS MOVED AND NOW IS INCLUDED IN MY THIGHS. CANNOT SEEM TO GET RELIEF FROM STOCKINGS, ULTRASOUNDS HAVE SHOWN NO CLOT ISSUES BUT THE S WELLING IS INCEDIBLE AND PAINFUL AS WELL mY SURGERY WAS jAN 20TH