Bone Biology
A 72-year-old female sustains a low-energy intertrochanteric femur fracture after a simple fall. DEXA scan reveals T-score -3.2 (severe osteoporosis). During case discussion, a junior resident asks why bone is strong yet flexible, and how osteoporosis affects bone quality. You explain that bone is a composite material with specific organic and inorganic components that work synergistically to provide both strength and toughness. Understanding bone composition is fundamental to comprehending fracture patterns, healing, and metabolic bone diseases. Regarding bone composition and structure:
Mark each as TRUE or FALSE
Bone is composed of 65% inorganic mineral (hydroxyapatite Ca10(PO4)6(OH)2), 25% organic matrix (90% ...
Type I collagen is the predominant structural protein in bone (90% of organic matrix), arranged in a...
Cortical (compact) bone comprises 20% of skeletal mass but 80% of bone surface area, undergoing more...
Bone exhibits a hierarchical structure across seven organizational levels from nanoscale (hydroxyapa...
The elastic modulus (stiffness) of bone is approximately 180-200 GPa, making it stiffer than steel (...
Answer the questions to see explanations
Click T (True) or F (False) for each option