Hey Chiara not to throw a spanner in the works but I had a friend who's dog had hip dysplasia and they tried a stem cell therapy which worked wonders.
He was a tad older mind, at 10 years old, and instead of an invasive procedure like a hip replacement, he had stem cells from his own body injected into his affected joints. Really made a difference in stabilising the hip and reducing the pain he was suffering from. When my friend went home to visit months after the treatment, his dog bounding down the stairs to meet him which he couldn't even attempt before.
I hope whatever you decide to go for, works well for Hugo.
