Lab tests after low bone density or fracture

Why labs may matter

Secondary contributors to bone fragility can include vitamin D deficiency, calcium or parathyroid problems, kidney disease, thyroid disease, malabsorption, inflammatory disease, some cancers, low sex hormones, medications, and other conditions. A major secondary osteoporosis review emphasizes that endocrine, kidney, liver, gastrointestinal, hematologic, inflammatory, medication-related, and nutrition-related contributors can be clinically important because some are treatable and some change medication choices. Evaluation usually starts with history, physical exam, DXA, fracture history, falls assessment, and selected lab studies.^1,2,4

Common lab categories to ask about

This table is educational. It is not a checklist that every person needs. Your clinician decides based on your story.

Questions to ask

• Are we looking for a secondary cause of bone loss or fracture?
• Which labs would change the plan if abnormal?
• Do my medicines, kidney function, digestive history, or hormone history change what should be tested?
• If labs are normal, what is the next step?
• If labs are abnormal, who should help interpret them?

Evidence review

Why labs matter

Low bone density or a fragility fracture is sometimes the first clue to another medical problem. Laboratory evaluation is not about ordering everything; it is about looking for common, treatable contributors that would change care.¹²

Secondary causes

Secondary osteoporosis can be related to glucocorticoids, endocrine disease, kidney disease, gastrointestinal disease and malabsorption, inflammatory disease, liver disease, diabetes-related complications, cancer therapy, and other medications. The size of the workup should fit the patient and the pattern.¹⁴⁵

Evaluation strategy

A practical lab review often considers calcium, kidney function, vitamin D status when relevant, thyroid/parathyroid clues, blood counts, liver tests, markers of malabsorption or inflammation when suggested by the history, and sex-hormone evaluation in selected patients. The history usually decides which tests belong.¹⁶

Treatment connection

Finding a secondary cause does not make the fracture less important. It can change the treatment plan: correct the driver when possible, reduce harmful exposures, choose medication with renal and metabolic context in mind, and avoid assuming that supplements alone solve the problem.²⁴

References

1. Ebeling PR, Nguyen HH, Aleksova J, Vincent AJ, Wong P, Milat F. Secondary osteoporosis. Endocr Rev. 2022;43(2):240-313. doi:10.1210/endrev/bnab028.
2. Morin SN, Leslie WD, Schousboe JT. Osteoporosis: a review. JAMA. 2025. doi:10.1001/jama.2025.6003.
3. Compston JE, McClung MR, Leslie WD. Osteoporosis. Lancet. 2019;393(10169):364-376. doi:10.1016/S0140-6736(18)32112-3.
4. Gasser RW, Kocijan R, Zendeli A, Resch H. Drug-induced osteoporosis. J Clin Med. 2026;15(3):993. doi:10.3390/jcm15030993.
5. Kapszewicz M, Michalska-Kasiczak M, Sewerynek E. Glucocorticoid-Induced Osteoporosis: Pathogenesis, the Impact of Different Administration Routes on Bone Mineral Density, and Fracture Risk and Treatment Options-A Narrative Review. J Clin Med. 2026. doi:10.3390/jcm15072488. PMID:41976789.
6. Walker MD, Shane E. Postmenopausal Osteoporosis. N Engl J Med. 2023. doi:10.1056/NEJMcp2307353. PMID:37991856.