confine a cat?!

Our furry friend came in one morning after a night of hunting, with a really bad limp - walking on three legs type of limp. We took the feline to the vet. to confirm what we knew, he had a broken leg, totally broken leg, like two pieces from one. His left rear leg just dangles. Poor kitty. We (the whole fam.) is so sad and hoping he can mend but it is hard! The vet said to keep him from walking and more importantly jumping up on furniture. How do you do that with a cat?! We borrowed a pet kennel, designed for a large dog, (thank you uncle Bruce!) but after adding the litter box, the cat only had enough space to lay down. How do you keep an active cat from being active? And it isn't for just a few days - it's for six weeks! And still our beloved pet may still have a gimp. I have resigned myself to having a three legged mouse trap but worry about getting thru. the next six weeks of nightly meowing/howling. We keep him comfortable (with vet prepared pain pills), cater to his needs by bring the food and water to him as he lounges on the comfy feather bed (when we can catsit) but he still wants to walk around, jump up on couches and be independent. Sigh. So how do you confine a cat so he can recuperate!? Isn't confined cat an oxymoron?