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Yes! If you can afford hydrotherapy, that would be great. They recommend aggressive PT for FCE, and hydrotherapy will really help him while he has trouble standing with one side more than the other, because the water will support him and let him begin using all four legs without falling.
If he is wetting his bed or wetting when you get him on his feet, you may want to get him some belly bands (male wraps). They are a wide belt that goes around the waist covering the male area, and you put an absorbent pad in them to catch urine.
Is he a big dog? It sounds like you have everything well in hand already.
The main thing they say is to keep upbeat around the dog, which it sounds like you are already doing. If you feel upset at some point and need to cry or something, do it where he can't see. Some dogs just get stressed by vet visits and the change of routine, but if you are sleeping with him and spending time with him, he knows you are there for him. The vast majority of FCE dogs will recover walking and go on to lead normal lives, you might tell him that.
I'm not sure why he was restless. Moaning and groaning it not something I've heard reported with FCE. There are some uncommon things that can actually go wrong, but they are very uncommon. Some dogs can develop GI ulceration if given steroids. Rarely a dog will bloat, which can be from many things including stress. Possibly he is just restless because he can't get up. They say any pain that was associated with the FCE is short lasting, not beyond a day or two. You might ask the vet about his restlessness and groaning, I don't know. If there is one side he normally lies on, perhaps he is on the wrong side and can't turn himself. Some dogs can turn themselves and some can't.
I went through that with my golden retriever, tried several harnesses (wasting money and time) until I found a solution that was good enough. They say you can use a bath towel for a sling but I find that requires a lot of grip strength to hold the towel with a large dog. A baby crib sheet would be less bulky to grab. A wide belt might work, like a carpenter's tool belt.
Here are some ideas for a homemade DIY harness that might work till you get a better one.
viewtopic.php?f=66&t=21612 canvas bag
viewtopic.php?f=66&t=21944 made with dog collars, very easy
viewtopic.php?f=66&t=21665 made of leashes (may not be big enough)
viewtopic.php?f=66&t=22066 padded backpack strap
viewtopic.php?f=66&t=21453 (requires sewing)
viewtopic.php?f=66&t=21226 wood frame harness, (need drill and saw)
viewtopic.php?f=66&t=21207 horse saddle girth
viewtopic.php?f=66&t=21393 (easy to put on)
http://www.lyonpuffpetsit.com/htmlslp/sling.html sweatshirt sling
viewtopic.php?f=66&t=21304 automobile tow strap
viewtopic.php?f=66&t=21258 Sabaka sling
If he keeps dribbling when you take him out, one solution is a male wrap. You put it on, escort him out, and remove it when you are out the door. They fasten around the waist with velcro so you should be able to get it off one-handed.
Tuesday will be here in no time. I am not sure how your hydrotherapy place will do things. With my dog, her first session in the treadmill was 5 minutes, the second session 10, the third 15, and so on. My dog didn't happen to like being in the water at first, but she came to love it. They also did other physical therapy exercises during the session. It is quite possible they will send you home with a list of exercises to do with your dog between sessions.
At home you can massage his legs and paws (or you may already be doing that). His body needs to remap the pathway from his brain to his toes, and any stimulus to his feet will give him something to work with. One person here reported her vet told her to brush the pads of her dog's feet with a toothbrush! You can also try resistance exercise with him lying down. Simply push up on the pads of his feet and see if he'll push back. My dog's physical therapist told me to work her paw pads as much as possible to improve "proprioception", which means learning to feel the feet again and know where they are in space and what they are doing. I even did "This little piggy" with her. The therapist didn't exactly tell me to do that, but my dog liked it! We rubbed her paw pads, and massaged her feet, and bicycled her legs gently.
There is a temporary phase that some (not the majority) of dogs go through during recovery from a spinal injury, where they will begin to lick or chew an affected area, commonly the feet or the male area. The theory is that it is like when you sleep on your arm funny and it goes numb, then it begins to tingle when it starts to wake up. Dogs will lick or chew trying to address that pins and needles sensation, and some of them have done it to the point of self-mutilation. A couple of dogs I know of were put down because they injured themselves so badly. If you notice your dog beginning to lick or chew an area, there is medication that will solve the problem (such as gabapentin or Lyrica), so I would call the vet right away, and put a cone collar on him to prevent any more chewing till you can get him on the meds. The cone collar is not a long term solution as dogs can get out of it, but it is better than nothing till you can get him the medication. This may never be an issue for him, but it is something to be aware of just in case.
I do not know if you or your husband will be taking him to PT. If someone has a big dog, you are going to have to get him into the car to drive over there, and then from the car into the house when you return home. But you could ask the PT place for help getting him into the building when you arrive, and back into the car after his session. You might ask them about that. Just tell them, "I've got a big dog I can barely handle, could someone help me get him into the building?" At the place I took my dog, they would even come out with a gurney and 2 techs to wheel a dog into the building if it was really big. I'm not sure if he's big (like a German Shepherd) or maybe even ginormous, but don't be afraid to ask for help.
Will be waiting to hear how his first session goes.