The Skeletal System

Key Assessment Statements

Distinguishing Skeleton Types

• Axial vs. Appendicular Skeleton
  • Axial: Protects vital organs, provides attachment, support, and movement.
  • Appendicular: Facilitates movement, attachment, support, stores minerals, produces red and white blood cells.

Types of Bones

• Long Bones: e.g., Femur, Humerus
• Short Bones: e.g., Carpals, Tarsals
• Flat Bones: e.g., Ribs, Cranium
• Irregular Bones: e.g., Vertebrae
• Sesamoid Bones: e.g., Patella

Long Bone Structure

• Diaphysis: Compact bone, long shaft covered by periosteum
• Epiphysis: Spongy bone, ends covered by articular cartilage
• Articular Cartilage: Reduces friction and absorbs shock
• Bone Marrow Cavity: Contains bone marrow
• Capillaries: Supply oxygenated blood
• Periosteum: Protective layer around bone

Anatomical Terminology

• Proximal: Closer to body center
• Distal: Further from body center
• Medial: Nearer to midline
• Lateral: Away from midline
• Inferior: Below or away from head
• Superior: Above or nearer to head
• Posterior: Behind or nearer back
• Anterior: In front of body

Connective Tissue Functions

• Tendons: Attach muscles to bones
• Ligaments: Connect bones at joints
• Cartilage: Cushions bone ends, absorbs shock, reduces friction

Joints and Movements

• Joint: Point where two bones meet
• Joint Types:
  • Fibrous: No movement
  • Cartilaginous: Limited movement
  • Synovial: Freely moving, most common
• Synovial Joint Features: Includes articular cartilage, synovial membrane, synovial fluid, bursae, meniscus, ligaments, articular capsule

Synovial Joint Types

• Hinge: Elbow, knee (flexion/extension)
• Pivot: Neck, radioulnar joint (rotation)
• Ball and Socket: Shoulder, hip (flexion, extension, adduction, abduction, rotation)
• Condyloid: Wrist (flexion, extension, adduction, abduction, circumduction)
• Saddle: Thumb (flexion, extension, adduction, abduction, circumduction)
• Gliding: Tarsal, carpal bones (gliding movements)

Movements in Synovial Joints

• Adduction: Movement towards midline
• Abduction: Movement away from midline
• Flexion: Decrease joint angle
• Extension: Increase joint angle
• Pronation: Palm faces down
• Supination: Palm faces up
• Elevation: Move structure up
• Depression: Move structure down
• Rotation: Turning around long axis
• Circumduction: Circular movement
• Eversion: Ankle turns outward
• Inversion: Ankle turns inward
• Plantar Flexion: Point foot down
• Dorsiflexion: Point foot up

These notes summarize the critical points regarding the skeletal system's structure and function, key anatomical terms, types of bones and joints, and movements possible within synovial joints. They provide a comprehensive overview suitable for review and study purposes.