The purpose of this study is to apply a novel advanced magnetic resonance imaging methodology to evaluate the response to drug intervention involving two treatment arms of postmenopausal participants with osteoporosis, randomized into either a teriparatide (Forteo™) or zoledronic acid (Reclast™) group.

The overall design is to determine and compare the effect of teriparatide and of zoledronic acid on trabecular architecture by magnetic resonance imaging of the midshaft tibia. Post-menopausal women, aged 60 or older with osteoporosis and/or at increased risk of fracture, will be randomized to receive either teriparatide or zoledronic acid. Trabecular microarchitecture, biomechanical parameters and bone mineral density will be examined at 0 and 12 months at 3T MRI.

Inclusion Criteria:

• Women
• Age ≥ 60 years
• Bone mineral density T-score of either the spine (L1-L4), total hip or femoral neck of ≤ - 2.0, or has a history of an osteoporotic fracture

Exclusion Criteria:

• Previous treatment with pamidronate, ibandronate, of more than 2 doses in 2 years and of zoledronic acid at any time
• Previous treatment with teriparatide, alendronate or risedronate of more than 2 months in the last 24 months
• Previous treatment with calcitonin within the previous year; previous treatment with an estrogen or selective estrogen modulator will not exclude a potential subject unless she has been taking it for < 1 year (a woman who discontinued estrogen or a selective estrogen receptor within the previous year will also be excluded)
• Other diseases known to affect bone, such as Paget's disease, Cushing's disease, hyperthyroidism, hyperparathyroidism, bone cancer and metastases to bone, and vitamin D deficiency
• Medications known to affect bone, such as anticonvulsants, high dose glucocorticoids (20 mg/day or more > 2 weeks within the previous 6 months)
• Current alcohol use > 3 drinks/day
• Untreated or unstable cardiac, pulmonary, liver (SGOT > 2X upper limit of normal) or renal disease (creatinine > 1.2 mg/dL) or uncontrolled diabetes (hemoglobin A1C > 8.0)
• Prior radiation therapy to the skeleton
• Cardiac pacemakers, ferromagnetic implants or brain aneurysm clips
• Claustrophobia
• Subjects whose initial MRI is of poor quality due to motion artifact will be asked to repeat the examination; if a repeat MRI is of poor quality due to motion artifact, the subject will be excluded from the study
• Abnormalities of the which delay esophageal emptying such as stricture or achalasia
• Inability to stand or sit upright for at least 30 minutes
• Hypocalcemia
• Uric acid level >7.5ml/dl
• Subjects with metallic objects in their bodies

Postmenopausal women

2 years

Adverse events were monitored/assessed without regard to the specific adverse event term. Please note that adverse events do include abnormal laboratory values at screening.

Insufficient Power