Tortoise:Could bladder infection/constipation cause limp rear limbs?He's dragging himself w front legs.?

I took him to the vet, who did x-rays and saw that he was 'backed up'. She gave me a laxative for him. She also saw 2 small objects on x-ray but couldn't tell if they were in the bowel or bladder. He has had 2 injections of enrofloxacin so far, and is to have 2 more, each 2 days apart. I took in a urine specimen (you can imagine how difficult it is to get a urine specimen from a tortoise!) and he appears to have a bladder infection. My question is: would a bladder infection and possible constipation cause a tortoise to drag his backside and have weak hind legs? This problem came up rather suddenly. Started with one leg, then within a day, both were pretty much useless. He seems to be improving, but his left hind leg is definitely faring the worst.