This is my friend's cat, Nummy, isn't he beautiful? Full Maine Coon, absolutely exquisite cat - if a little slow...he is adorably stupid...
But, common in Maine Coons, Nummy has been diagnosed with feline hip dysplasia. It can happen a lot in Maine Coons and the bigger the animal the more serious the problem. As you can see Nummy is a VERY big cat and his condition is serious (this picture was taken before the symptoms settled in).
He is due to have his femurs cropped (the failing balls of the joint cut off) in due course, and I did some research.
"Restricting exercise, such as limiting access to outdoors or the ability to climb up on objects, can be helpful as well. For severely affected cats, a surgery called a femoral head and neck excision arthroplasty is widely available that removes the damaged tissue. Cats that have had this surgery can usually expect a full return of hip function and freedom from pain and discomfort once post-operative healing has occurred."
That sounds so positive, it would be wonderful if this big chap got another chance - he's only 18 months old and that is just too young to creak about like me!