The following morning, Enzo finds that he can barely move. He says that by now he's eight years old, which is too young to suffer from an arthritic condition in his hips, although that's exactly what the problem is. He tells the reader that while it's an unpleasant condition, he's happy he can focus on his own difficulties rather than dwell on the fact that Zoë is stranded with Trish and Maxwell.
Enzo's age is finally beginning to show, although like Denny, Enzo looks for the positive aspects of the situation. We see how he's further characterizing Trish and Maxwell as evil given the language he uses to describe the situation. Zoë being “stranded” paints a very different picture than a word like “staying” might.
Enzo explains that he learned his hips were abnormal very young, when he became old enough to go to dog parks. He realized that keeping his hind legs together, despite being more comfortable, was a sign of defective hips. He didn't want to be labeled a misfit, so he learned to walk and run normally. As he matured and cartilage began to wear away, the pain increased, although he tried to hide the problem. He wonders that maybe he's more like Eve than he's admitted, since he distrusts the medical world and behaved in such a way as to avoid a diagnosis that would bring about his untimely demise.
Following Eve's death, Enzo begins to realize and voice the fact that he and Eve were probably more alike than he ever considered. This retroactively adds another layer of interest to Eve and Enzo's relationship, as the reader is then made to wonder how else the two were alike.
Enzo continues and says that he doesn't know why Eve distrusted medicine, but his own distrust stems from an event that took place when he was a week or two old. The alpha man introduced Enzo to a friend of his, Doc, who examined Enzo's front legs and said his dewclaws should be removed. The alpha man offered to hold Enzo, but Doc said he needed anesthetic. The alpha man said he wasn't wasting money on a dog, and Doc complied. He snipped off Enzo's dewclaws one at a time, and the pain was horrible and intense. Blood ran everywhere.
Remember that Enzo believes that the dewclaw is indicative of a pre-emergent thumb in dogs. Essentially, the alpha man and Doc remove Enzo's most prominent physical connection to his belief that he's more human than dog. The alpha man further is characterized as being wholly evil when he refuses to pay for pain relief for Enzo, essentially adding insult to injury.
When Doc applied salve to the wounds, he whispered to Enzo that it's a mean bastard who won't pay for anesthetic, but Enzo tells the reader that it's a mean bastard who will cut without anesthetic for money, and that's why he distrusts doctors.
Money is equated with human evil several times throughout the novel.
Returning to the present, Denny takes Enzo to the vet where he is diagnosed with hip dysplasia and prescribed anti-inflammatory medication. On the ride home, Denny repeats the diagnosis and shakes his head, and Enzo tells the reader that if he'd had fingers, he'd have shoved them into his ears to avoid listening. He knows that the diagnosis will bring his slow and painful end. He repeats that the visible becomes inevitable and the car goes where the eyes go. Enzo says that he saw what happened with Eve, that she was unable to escape when those around her agreed that she would die. Enzo says that, unlike Eve, he's going to try to look away from his diagnosis.
Despite the similarities that Enzo just drew between himself and Eve, he's setting out to differentiate himself from her in his handling of his diagnosis. By invoking driving truths again, Enzo ties his resolution to look away from his diagnosis back to his ideas of destiny, and he also ties ideas of humanity to it by mentioning his hypothetical fingers. Essentially, he would've used his human traits to avoid his destiny.