
I don't know if this will help but my boy partially tore his cruciate the christmas before last. The vet was all set for surgery but told me I would be looking to replace his hip in a year and possibly the other in 24months. The specialist was called to evaluate him and said no to surgery. He recommended a product by lintbells 'yumove'. Its not cheap and I have had to buy online, but after 4 weeks of complete rest and 3 tablets a day, we decreased the dose to 2 tablets and gentle exercise. Within 4 months there was marked change and he actually seems faster now! He only has 1 tablet a day and even then I sometimes forget.
The only thing I must say is that is contains green lipped mussels and will cause allerhic reactions if the dog is allergic to fish/shellfish. On the plus side though, you don't need to convert dosage to the size of your dog or worry about absorption rate.
Not sure if this helps but might be worth looking into.