Osteoporosis Differential Diagnoses

Updated: Jan 20, 2021
  • Author: Rachel Elizabeth Whitaker Elam, MD, MSc; Chief Editor: Herbert S Diamond, MD  more...
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DDx

Diagnostic Considerations

The differential diagnosis of osteoporosis is very extensive. When dealing with reduced bone density, always rule out the other possible causes before treating the patient for osteoporosis. Many patients have a coexisting cause of bone loss.

The differential diagnosis of an atraumatic compression fracture may include osteomalacia, tumor, osteonecrosis, infection, and other bone-softening metabolic disorders. Metastatic bone disease should always be ruled out when a patient incurs multiple fractures.

Osteoporosis may be confused with osteomalacia, but in osteoporosis the bones are porous and brittle, whereas in osteomalacia the bones are soft. This difference in bone consistency is related to the ratio of mineral to organic material (principally, collagen). In osteoporosis, the mineral-to-collagen ratio is within the reference range, whereas in osteomalacia, the proportion of mineral composition is reduced relative to organic matrix content.

Sometimes a patient's first fracture is the sentinel event that alerts the clinician to an underlying disorder leading to osteoporosis.

Other conditions to be considered include the following:

  • Leukemia
  • Lymphoma
  • Fractures secondary to bone metastases from cancer
  • Renal osteodystrophy

Differential Diagnoses