The purpose of this study is to evaluate the effects of teriparatide on skeleton images in postmenopausal women with osteoporosis. Teriparatide is a bone formation agent that stimulates the production of new bone in the skeleton. This process of bone formation can be studied using a technique commonly referred to as a bone scan or nuclear scintigraphy. This trial will test whether bone scans will identify areas of the skeleton that are forming new bone during teriparatide therapy. It also will study what these areas look like after therapy is stopped.