Histology Course A III 1a Department of Pathology, University of Zurich Histology Course

A III 1a osteoporosis HE  
  ICD-10: M80
82-year-old female suffered from chronic heart failure. She experienced bone pain and had a femoral neck fracture (specimen from autopsy).

- The scant trabeculae are thinned and have lost their interconnections.
- Osteoblasts and osteoclasts are rare. However, a number of trabeculae display resorptive pitting.
- The medullary spaces are wide.
- The bone marrow is distinctly hypercellular with approximately 60% of red bone marrow and 40% of fat. The hypercellularity is mainly due to an increased granulopoiesis.

In osteoporosis, the bone displays normal mineralization. In contrast, osteomalacia is characterized by defective mineralization. Histological examination reveals an increase in the amount of unmineralized bone and disorganized trabecular architecture. Of note, mineralization can only be assessed using special techniques not requiring decalcification of tissue specimens prior to staining.
The increase in granulopoiesis indicates that the patient suffered in addition from an infection.