Lecture Notes: Anatomy and Physiology of the Skeletal System

Introduction

• The lecture humorously contrasts teaching college-level anatomy with a simple song.
• Focuses on detailed understanding of the skeletal system beyond just bones.

Components of the Skeletal System

• Bones, Cartilage, and Connective Tissue: Integral for function and movement.
• Joints: Vital for physiological function.
  • More joints than bones in the body.
  • Movements occur when muscles contract across joints.

Structure of the Skeleton

• Divided into Two Parts:
  • Axial Skeleton: 80 midline bones.
    • Skull: 8 cranial, 14 facial bones.
    • Vertebral Column: 33 irregular bones.
    • Thoracic Cage: 12 pairs of ribs and sternum.
  • Appendicular Skeleton: Upper/lower limbs and girdles.
    • Similar setup in arms and legs: "One bone, two bones, lots of bones, and digits."

Physiology of the Skeleton

• Focus on joints.
• Joint Classifications:
  • Structural: Based on material binding bones (fibrous, cartilaginous, synovial).
  • Functional: Based on joint movement (synarthroses, amphiarthroses, diarthroses).

Joint Details

• Fibrous Joints: Dense connective tissue, mostly immovable.
• Cartilaginous Joints: Unite bones with cartilage, slightly movable.
• Synovial Joints: Freely movable with synovial fluid-filled cavity.
  • Important for various activities and movements.

Types of Movement

• Gliding Movements: Flat bone surfaces glide over one another.
• Angular Movements:
  • Flexion and Extension: Decreasing/increasing joint angle.
  • Abduction and Adduction: Movement away/toward the body's midline.
  • Circumduction: Combination of movements for circular motion.
• Rotational Movements: Bone turns around its axis.
• Special Movements: Unique to certain joints (e.g., opposition in thumbs).

Real-Life Application

• Synovial joints facilitate various activities, such as sports and dance.
• Dance metaphor used to illustrate joint functions and movements.

Conclusion

• Overview of the skeletal structure and joint functionality.
• Encouragement to engage with educational resources like Crash Course.

Acknowledgments

• Thanks to contributors and educational platforms that support ongoing learning initiatives.