Cortical bone

Definition

Cortical bone is the dense, outer layer of bone tissue that provides strength and protection to the inner, more porous structures. It is crucial in supporting weight and resisting bending forces, making it a key player in the mechanics of bone and cartilage. Its structural integrity is vital for overall skeletal stability and function.

5 Must Know Facts For Your Next Test

1. Cortical bone accounts for about 80% of the total bone mass in an adult human skeleton, highlighting its importance in overall skeletal structure.
2. The thickness of cortical bone varies across different bones and regions of the body, adapting to the specific mechanical loads experienced.
3. Cortical bone is highly organized and consists of tightly packed osteons, which provide strength and resilience against compressive forces.
4. This type of bone has a lower turnover rate compared to trabecular bone, meaning it is slower to adapt to changes in mechanical stress or injury.
5. Cortical bone plays a critical role in protecting the inner trabecular bone, which contains the marrow where blood cell production occurs.

Review Questions

• How does the structure of cortical bone contribute to its function in supporting weight and resisting forces?
  • Cortical bone has a dense structure composed of tightly packed osteons that provide significant strength and rigidity. This arrangement allows cortical bone to effectively support weight from the body and resist bending or compressive forces during physical activities. The thickness of cortical bone can vary depending on its location in the body, adapting to specific functional demands and mechanical stresses placed upon it.
• In what ways does cortical bone interact with trabecular bone during activities that involve load-bearing?
  • Cortical and trabecular bones work together to handle mechanical loads. While cortical bone provides overall strength and stability, trabecular bone acts as a shock absorber due to its porous structure. During load-bearing activities, cortical bone resists external forces while trabecular bone helps distribute these forces throughout the skeletal system, preventing injury and enhancing performance during dynamic movements.
• Evaluate the impact of aging on cortical bone density and how this may affect athletic performance and injury risk.
  • As individuals age, there is a natural decline in cortical bone density due to changes in metabolism and hormonal levels. This reduction leads to an increased risk of fractures and decreased overall skeletal strength, which can significantly impact athletic performance. Weaker cortical bones may not withstand the same mechanical loads as before, increasing susceptibility to injuries during high-impact sports or activities. Maintaining bone health through nutrition and exercise is crucial for minimizing these risks as one ages.

Related terms

trabecular bone: Trabecular bone, also known as spongy bone, is the inner, more porous part of the bone that helps absorb shock and reduce weight while maintaining structural integrity.

osteons: Osteons are the basic structural units of cortical bone, consisting of concentric layers of mineralized matrix surrounding a central canal containing blood vessels and nerves.

bone remodeling:

Bone remodeling is the ongoing process where old bone tissue is replaced with new tissue, crucial for maintaining bone strength and health throughout life.