Lecture Notes: Skeletal System

Introduction

• Lecture on the human skeletal system without using simplistic songs.
• Importance of understanding more than just bone names.

Anatomy of the Skeletal System

• Components: Bones, cartilage, and fibrous connective tissue.
• Joints: Critical for movement; more joints than bones in the body.

Division of the Skeleton

• Axial Skeleton
  • 80 bones including skull, vertebral column, and thoracic cage.
  • Skull: 8 cranial bones, 14 facial bones, functions in protection and sensory facilitation.
  • Vertebral Column: 33 bones, provides central support, protects the spinal cord.
  • Thoracic Cage: 12 pairs of ribs and sternum, protects vital organs.
• Appendicular Skeleton
  • Includes limbs and girdles.
  • Upper and lower limbs have similar setup ("one bone, two bones, lots of bones and digits").

Physiology of the Skeleton

• Role of Joints: Facilitate movement.
• Structural Classification of Joints
  • Fibrous Joints: Dense connective tissue, mostly immovable (e.g., skull sutures).
  • Cartilaginous Joints: Use cartilage, limited movement.
  • Synovial Joints: Fluid-filled cavities, freely movable, most common in body.
• Functional Classification of Joints
  • Synarthroses: Immovable joints.
  • Amphiarthroses: Slightly movable joints.
  • Diarthroses: Fully movable joints.

Movements and Joint Types

• Gliding Movements: Occur in gliding joints, e.g., wrists.
• Angular Movements
  • Flexion: Decreasing angle between bones.
  • Extension: Increasing angle.
  • Hyperextension: Beyond normal range.
  • Abduction: Moving limbs away from body.
  • Adduction: Moving limbs toward body.
  • Circumduction: Circular movement.
• Rotational Movements
  • Ball and Socket Joints: Allow rotation (e.g., shoulder, hip).
  • Importance of joint flexibility vs. stability.
• Special Movements
  • Opposition: Thumb movement across palm.
  • Supination/Pronation: Rotational movement of palm.

Conclusion

• Emphasis on understanding structure and functionality of skeletal system for mature learning.
• Acknowledgements to contributors and sponsors.