Bone Health and Osteoporosis Lecture Review

A comprehensive set of 150 flashcards covering essential vocabulary and concepts related to bone health and osteoporosis.

Chronic Diseases Effects on Bone Health

Chronic diseases like diabetes can affect bone density, healing, and overall integrity.

Epiphyseal Line

In adults, it marks the former location of the epiphyseal plate.

Bone Microenvironment

The microenvironment provides necessary nutrients and chemical signals for bone cell function.

Osteoporosis Prevention

Prevention includes adequate nutrition (calcium and vitamin D), regular exercise, and medication.

Hematoma Role in Bone Repair

A hematoma forms at the fracture site, stabilizing fragments and delivering repair cells.

Wormian Bones

Flat bones typically found in the sutures of the skull.

Paget’s Disease

A chronic disorder causing enlarged and misshapen bones due to abnormal remodeling.

Endosteum

A thin layer of CT lining internal bone surfaces, containing osteoprogenitor cells, osteoblasts, and osteoclasts.

Role of Calcium in Bone Physiology

Calcium is essential for bone strength and is stored in bones for bodily functions.

Genetic Factors Influencing Bone Health

Includes inherited conditions, genetic predispositions to bone diseases, and variations in bone density.

Trabeculae Alignment

Trabeculae align along lines of mechanical stress.

Types of Cartilage in Skeletal System

Hyaline cartilage (ribs to sternum, articular cartilage) and fibrocartilage (intervertebral discs, menisci).

Skeleton's Role in Electrolyte Balance

Stores calcium and phosphate ions.

Perforating Canals

Join central canals, allowing passage of blood vessels and nerves.

Trabeculae Arrangement Importance

Provides strength with minimal weight, supporting stress lines.

Bone Matrix Composition

Organic matter is osteoid (collagen, protein-carbohydrate complexes) and inorganic matter is mainly hydroxyapatite.

Red Bone Marrow Location in Children vs Adults

Children: in spongy bone and medullary cavities; Adults: in skull, vertebrae, ribs, sternum, ossa coxae, proximal humerus and femur.

Exercise Impact on Bone Health

Increases bone density and strength.

Bone Healing Complications

Includes non-union, malunion, infection, and delayed healing.

Hormones and Bone Density Relationship

Hormones regulate bone density by influencing growth, resorption, and calcium homeostasis.

Central Canals

Vertical channels in osteons containing blood vessels, nerves, and lymphatic vessels.

Structure of Flat, Short, and Irregular Bones

They have a sandwich-like structure with two layers of compact bone enclosing a spongy layer.

Consequences of Bone Resorption and Formation Imbalance

Can lead to osteoporosis (more resorption) or osteopetrosis (more formation).

Growth Hormones Role

Stimulate bone growth and cartilage proliferation at growth plates.

Bone Health Diagnostic Tools

Bone density scans (DEXA), X-rays, and bone markers.

Enzyme Activities in Bone Remodeling

Enzymes from osteoblasts and osteoclasts facilitate formation and resorption.

Functions of the Skeleton

Support, protection, movement, electrolyte balance and storage, hemopoiesis, and adipose storage.

Difference Between Compact and Spongy Bone

Compact bone is dense and forms the outer shell, while spongy bone has a lattice-like structure.

Basic Structural Unit of Compact Bone

Osteons, or Haversian systems.

Role of Hydroxyapatite

Provides hardness and strength to the bone matrix.

Spaces in Spongy Bone Utilization

Filled with red bone marrow.

Vitamin D Contribution to Bone Health

Enhances calcium absorption from the diet for bone mineralization.

Bone Composition Percentages

Compact (80%) and Spongy (20%).

Diploe Function

Spongy bone layer in the cranium that absorbs shock.

Types of Bones in Human Body

Long (limbs), short (carpals), flat (skull), irregular (vertebrae), sesamoid, Wormian bones.

Sesamoid Bones Classification

Type of short bone found embedded in tendons.

Four Types of Bone Cells

Osteoprogenitor (stem cells), osteoblasts (build bone), osteocytes (maintain bone), osteoclasts (bone resorption).

Bisphosphonates Mechanism

Inhibit osteoclast activity, slowing bone resorption and preserving bone density.

Intramembranous Ossification Description

Direct formation of bone within sheets of connective tissue, occurring in flat bones.

Yellow Bone Marrow Function

Stores fat and can convert back to red marrow during severe anemia.

Blood Supply to Bones

Highly vascularized; nutrient foramina are openings for blood vessels.

Osteoblasts Roles

Synthesize new bone matrix and facilitate mineralization.

Significance of Remodeling Phase

Restores bone to its original shape by replacing old bone with new tissue.

Endochondral Ossification Definition

Process of bone formation from cartilage precursor, critical for long bone development.

Callus Formation During Healing

Fibrocartilage and bone bridge the fracture gap.

Spongy Bones Structure

Lacks osteons and central canals, has trabeculae instead.

Mechanical Stress Affect on Bone

Stimulates remodeling, increasing bone density.

Tendons vs Ligaments Structure

Tendons connect muscles to bones; ligaments connect bones to bones.

Perforating or Sharpeys Fibers Role

Collagen fibers anchoring the periosteum to compact bone.

Factors Influencing Bone Growth

Hormones, nutrition, mechanical stress, and genetics.

Osteocytes Location & Communication

Reside in lacunae and communicate via canaliculi.

Key Structural Elements of Long Bone

Epiphysis, articular cartilage, epiphyseal plates, diaphysis, spongy bone, compact bone, periosteum, endosteum, medullary cavity.

Bone Mineral Homeostasis

Maintained by storing and releasing minerals like calcium and phosphate.

Metaphysis Role in Growth

Where new bone is added during interstitial growth, adjacent to epiphyseal plate.

Inflammation Effect on Bone Health

Chronic inflammation can increase bone resorption and risk osteoporosis.

Age Effect on Bone Density

Bone density decreases with age, leading to osteoporosis.

Collagen and Hydroxyapatite Roles

Collagen provides flexible strength; hydroxyapatite provides hardness.

Bone Ground Substances

Includes hydroxyapatite and chondroitin sulfate, providing structure and resilience.

Spongy Bone Structure Support

Trabeculae align along stress lines for efficient loading.

Stages of Fracture Healing

Hematoma formation, fibrocartilaginous callus formation, bony callus formation, bone remodeling.

Bone Interaction with Other Systems

Interacts with muscular for movement, and circulatory and endocrine systems for mineral balance.

Lifestyle Choices Affect on Bone Health

Diet, physical activity, smoking, and alcohol consumption significantly impact bone health.

Nerves Innervating Bones

Mainly sensory nerves accompany blood vessels, innervating bone, periosteum, and marrow cavity.

External Factors Affecting Bone Remodeling

Physical activity, diet, hormones, and lifestyle choices.

Lamellae Function in Compact Bone

Concentric layers of matrix that strengthen compact bone.

Trabeculae vs Osteons

Trabeculae are rod-like structures in spongy bone without central canals; osteons have central canals in compact bone.

Skeleton Composition Ratio

Three-fourths compact bone and one-fourth spongy bone by weight.

Removal of Hydroxyapatite Effect

Bone becomes too bendable; removal of collagen makes bone too brittle.

Nutritional Factors for Bone Development

Calcium, vitamin D, protein, and minerals like phosphorus and magnesium.

Epiphyseal Plate Function

Growth plate made of hyaline cartilage that enables length growth.

Hemopoiesis Definition

Formation of blood cells, primarily in red bone marrow.

Osteoclasts vs Osteoblasts Function

Osteoclasts resorb bone tissue; osteoblasts build it.

Red vs Yellow Bone Marrow

Red marrow is hematopoietic (blood forming), yellow marrow stores fat.

Sex Hormones Effect on Bone Development

Estrogen and testosterone stimulate bone growth and epiphyseal plate closure.

Osteoporosis Definition

Condition where bones become brittle due to loss of density.

Estrogen Replacement Therapy Effect on Bone Health

Slows bone resorption but may increase health risks.

Nutrition's Role in Bone Growth

Lack of calcium, protein, and nutrients causes bones to be small.

Ossification Beginning in Embryo

Begins between the 8th and 12th weeks.

Calcitriol Function as Hormone

Raises blood calcium concentration.

Parathyroid Hormone (PTH) Function

Raises blood calcium levels.

PTH in Osteoporosis Treatments

Slows bone loss when given as injection.

PTH Mechanisms Effect on Bone

Increases bone resorption, reduces deposition, controls calcium excretion.

Trabeculae Definition

Supporting structure of spongy bone, thins in osteoporosis.

Lifestyle Choices for Osteoporosis Prevention

Regular exercise and a bone-healthy diet.

Hypocalcemia Symptoms

Muscle spasms, seizures, and irregular heart rhythms.

Calcitonin Importance by Age

Most important in children.

Calcium and Vitamin D Importance

Essential for bone mineralization and density.

Ossification Definition

Formation of bone.

Interstitial Bone Growth Definition

Bones increase in length through cartilage growth.

Calcitriol Effect on Calcium Levels

Increases absorption from intestines, resorption from skeleton, and kidney reabsorption.

Hormones and Mechanical Stress Effect on Remodeling

They regulate osteoblast and osteoclast activities.

Hormones in Calcium Homeostasis

Calcitriol, Calcitonin, Parathyroid hormone.

Dietary Changes for Bone Remodeling

Intake of calcium, vitamin D, and protein.

Estrogen Influence on Bone Density

Maintains density by inhibiting osteoclast resorption.

PTH Mechanisms for Blood Calcium

Increases osteoclast numbers, reduces osteoblast activity, decreases calcium excretion.

Bone Elongation During Growth

Occurs through cartilage growth in epiphyseal plate.

Osteoblasts, Osteocytes, Osteoclasts Roles in Remodeling

They coordinate to replace 20% of the skeleton yearly.

Mechanical Stress Effect on Remodeling

Increases bone mass and synthesis of osteoid.

Aging Effects on Bones

Decreased tensile strength, increased brittleness, and higher fracture risk.

Osteoclasts and Osteoblasts Interaction

Osteoclasts resorb bone while osteoblasts form new bone.