The pt has Paget's disease of the bone aka Osteitis deformans. ISOLATED INCREASE IN ALK PHOS = PAGETS!!! always.
Feel like this question is actually pretty tough. I mean, I think of Pagets causing:
Enlarged Head (e.g. hats won't fit) Chalk stick fractures (we don't see any fractures on this guys X-rays, and his backpain is due to sclerosis of his vertebra [not fractures]) High output HF (due to AV shunts); Hearing difficulties (none of thet in his guy) Osteosarcoma
Only thing we're given is that he has verebral cortical thinning, which could be d/t lots of stuff. He's old (RF) and that's about it.