Yes, they are tough, aren't they... yes, he must have broken it.
The eye problem is entropion (the eye lids roll inwards) and he also has ingrowing lashes. I hope we've found a good eye surgeon now. We've taken him to other eye vets before but haven't felt we wanted them to operate on him. This vet is young, very professional, and actually did her residency at UC Davis which probably means she is good, and she has a steady hand - amazingly enough she pulled ingrowing eye lashes out of Castor's eye with a pair of tweezers as we were talking with her about the surgery! And it's at a good vet hospital where Castor will stay over so that they monitor him for 24h or so after the surgery. The vet gave us a cone and said we'd better start practising before surgery as Castor will probably not like it (and she was right).