[Trabecular bone microarchitecture and male osteoporosis]

Area of Science:

• Orthopedics
• Bone Biology
• Gerontology

Background:

• Fragility fractures in men increase with declining bone mineral density (BMD).
• Vertebral mechanical strength depends on both BMD and trabecular bone architecture.
• Osteoporosis in men is characterized by reduced BMD and potentially altered bone structure.

Purpose of the Study:

• To investigate the relationship between trabecular bone architectural changes and vertebral crush fractures in men with osteoporosis.
• To compare bone architecture parameters between osteoporotic men with and without vertebral fractures.
• To identify key architectural determinants of osteoporotic fractures in the male population.

Main Methods:

• Recruited 44 male patients with osteoporosis and 11 male controls.
• Acquired spine radiographs, hip and lumbar spine BMD, and transiliac bone biopsies.
• Performed histomorphometric analysis to determine trabecular bone volume (BV/TV), thickness (Tb.Th), number (Tb.N), Trabecular Bone Pattern factor (TBPf), Inter Connectivity Index (ICI), Node count, and Star volume.

Main Results:

• Osteoporotic men showed lower Tb.Th, Tb.N, and Node count, but higher TBPf, ICI, and Star volume compared to controls.
• Exponential regressions revealed strong correlations between BV/TV and TBPf, ICI, and Star volume.
• Patients with vertebral fractures had significantly higher ICI and TBPf, and lower Node count, despite no significant differences in BMD or BV/TV.

Conclusions:

• Altered trabecular bone architecture is a primary factor in osteoporotic fractures in men.
• Specific architectural parameters like ICI and TBPf are critical indicators of fracture risk.
• Focusing on bone structure, beyond just density, is essential for understanding and managing male osteoporosis.