Precision Medicine Approach for Osteoporosis - Follow Up Study

This will be a prospective, longitudinal crossover trial for participants who have completed therapy in the main trial - Novel precision medicine approach to treatment of osteoporosis based on bone turnover. EIRB#70781. Participants will be informed of the continuation / follow-up study at enrollment into the main trial. Participants will be approached for further participation in the continuation trial near the end of the initial 12 months treatment period. Consent will be obtained at the final visit of the main trial and crossover therapy will be initiated at that time. Participants in Group 1 low turnover, who have received Teriparatide in the main trial and if it is determined that the participant did not respond well to therapy; will be assigned to Alendronate for 12 months. Participants in Group 2 low turnover who received Alendronate in the main trial and if it is determined that the participant did not respond well to therapy; will be assigned to Teriparatide for 12 months. Participants in Group 2 low turnover who received Alendronate in the main trial and if it is determined that the participant responded to therapy; will be continued on Alendronate for 12 months.