Senile patients with low back pain and radiolucency in the same lesion are usually diagnosed as osteoporosis. Some of them should be diagnosed as osteomalacia.
We reported two cases of senile osteomalacia with pseudo-arthrosis of pelvis and ribs, whose laboratory findings were as follows; the serum alkaline phosphatase was elevated, and the 25-OH vitamin D was decreased. They were treated with 1α-OH-D3.
