Anatomy Lecture: Cartilage and Skeletal System

Introduction

• Continuation of anatomy playlist.
• Previous topics: anatomical positions, skin, fascia, tendons, etc.

Cartilage Overview

• Found at articular surfaces (where bones articulate).
• Characteristics:
  • Supporting tissue: firm, elastic, flexible.
  • No vessels, lymphatics, nerves, leading to poor regeneration.

Human Skeleton

• Endoskeleton: inside the body.
• Components:
  • Axial Skeleton: skull, vertebral column, rib cage.
  • Appendicular Skeleton: upper and lower extremities.

Upper Extremities

• Shoulder (pectoral) girdle includes scapula and clavicle.
• Arm bones: humerus, radius, ulna.
• Hand bones: carpal bones, metacarpal bones, phalanges.

Lower Extremities

• Pelvic girdle (hip bone).
• Leg bones: femur, tibia, fibula.
• Foot bones: tarsals, metatarsals, phalanges.

Embryological Origin

• Bone, cartilage, muscles, tendons, ligaments from mesenchyme (mesoderm).
• Four tissue types: epithelium, connective tissue, muscle tissue, nerve tissue.

Bone Structure

• Diaphysis: shaft, compact bone.
• Epiphysis: ends, spongy bone.
• Covered by periosteum, cartilage by perichondrium.

Cartilage Function

• Helps growth (epiphyseal cartilage plate).
• Endochondral Ossification: cartilage dies, bone forms on top.

Bone vs. Cartilage

• Matrix: Bone is hard, cartilage is firm.
• Collagen:
  • Bone: Type 1.
  • Cartilage: Type 2 (also types 5 and 6).
• Vascularity: Bone vascular, cartilage avascular.

Cells and Minerals

• Bones:
  • Cells: osteoblasts, osteoclasts, osteocytes.
  • Minerals: calcified, hydroxyapatite.
• Cartilage:
  • Cells: chondroblasts, chondrocytes.
  • Not calcified, mostly water.

Types of Collagen

• Type 1: Bone.
• Type 2: Cartilage.
• Type 3: Blood vessels.
• Type 4: Basement membrane.
• Type 5: Hair, placenta.

Diseases and Conditions

• Chondrocalcinosis: Calcium in cartilage, seen in pseudogout.
• Inflammation Terms:
  • Tendinitis, myositis, dermatitis, fasciitis, bursitis, enthesitis, osteitis, chondritis.

Cartilage Types

• Hyaline, fibrocartilage, elastic cartilage.

Conclusion

• Clinical relevance and further studies in related playlists (e.g., Rheumatology).
• Endocrine pharmacology course offering.
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