Main Functions of Skeletal System
Support: Provides structure and shape to the body.
Protection: Shields vital organs, e.g., cranium protects the brain.
Movement: Muscles attach to bones for leverage and motion.
Mineral Storage: Stores minerals like calcium and phosphorus.
Blood Cell Formation: Hematopoiesis occurs in the red marrow.
Flexion: Decreasing the angle between bones.
Extension: Increasing the angle between bones.
Abduction: Moving a limb away from the midline.
Adduction: Moving a limb toward the midline.
Circumduction: Circular movement of a limb.
Rotation: Moving a bone around its axis.
Development: The skeleton starts as cartilage.
Ossification: Cartilage is replaced by mineralized bone over time.
Growth: Bones lengthen and widen through cellular activities of osteoblasts and osteoclasts.
Osteoarthritis: Degeneration of joint cartilage.
Rheumatoid Arthritis: Autoimmune disorder affecting joints.
Osteoporosis: Loss of bone density, increasing fracture risk.
Osteomyelitis: Bone infection usually caused by bacteria.
Abduction: Movement away from the midline.
Compact Bone: Dense bone tissue; forms outer layer.
Diaphysis: Shaft of a long bone.
Osteocytes: Bone cells maintaining bone tissue.
Epiphysis: End part of a long bone, contributing to joint structure.
Synovial Fluid: Lubricant found in joint cavities.
Axial Skeleton: Includes skull, vertebral column, and rib cage.
Appendicular Skeleton: Comprises limbs and girdles (shoulder and pelvic).
Long Bones: Humerus, femur.
Short Bones: Carpals, tarsals.
Flat Bones: Sternum, skull bones.
Irregular Bones: Vertebrae, some facial bones.
Hematoma Formation: Blood clots form at fracture site.
Soft Callus Formation: Cartilage develops to stabilize fracture.
Hard Callus Formation: Bone replaces cartilage.
Remodeling: Compact bone develops and shape is refined via activity of osteoblasts and osteoclasts.
Diarthroses (Freely Movable): Includes ball-and-socket, hinge, pivot joints.
Amphiarthroses (Slightly Movable): Like the ribs articulation.
Synarthroses (Immovable): Sutures of the skull.
Greenstick: Incomplete fracture common in children.
Comminuted: Bone shatters into multiple pieces.
Open/Compound: Broken bone penetrates skin.
Closed/Simple: No skin penetration.
Bones lose density and strength with age leading to conditions like osteoporosis.
Cartilage loses hydration, causing joint stiffness.
Knowledge of bone anatomy and functionality is critical for understanding injuries and disorders.
Maintaining bone health requires attention to nutrition (calcium, vitamin D) and physical activity.