Bone Quiz (BMS Learning Outcomes)

Bone Composition and Development

• Bone is composed of 40-50% inorganic minerals (e.g., calcium, phosphate), 30-40% organic compounds (e.g., collagen), and 20% water.
• Key structural components include osteocyte cells, collagen fibers, and an intracellular matrix containing inorganic salts.

Bone Types and Locations

• Long bones: Have a diaphysis (shaft) and two articular surfaces (ends), with a central marrow cavity. Examples include the femur and humerus.
• Sesamoid bones: Embedded within tendons, like the patella.
• Flat bones: Thin and often curved, providing protection (e.g., skull bones).
• Short bones: Cube-shaped (e.g., carpals and tarsals).
• Irregular bones: Irregular shapes (e.g., vertebrae).

Bone Tissue Types

• Compact bone: Dense and strong bone tissue forming the outer layer.
• Cancellous (spongy) bone: Porous inner layer with a lattice-like structure, providing strength with less density.

Bone Functions

• Protection: Protecting internal organs.
• Shape: Providing structural support and shape to the body.
• Movement: Providing attachment sites for muscles and enabling joint movement.
• Blood production: Producing red blood cells in bone marrow.
• Mineral storage: Storing calcium and phosphate.
• Sound transmission: Conducting sound waves to the inner ear.

Bone Healing Process

• Primary callus: Fibrocartilaginous callus forms within the first months following a fracture.
• Resorption/Bone formation: Dead bone is removed, and spongy bone formation occurs.
• Callus size: Affected by fracture site immobility; less movement results in a smaller callus.
• Secondary callus: Spongy bone is gradually replaced by stronger lamellar bone, uniting the fracture.
• Remodeling: The bone shape is restored to its original form, a process taking several years.

Factors Affecting Bone Healing

• Delays: Infection, bone fragments, poor blood supply, old age, certain medications (like steroids), and an inadequate host response.
• Improvements: Limited movement, pain relief medication, proper nutrition, age (younger is better), and appropriate guided movement under professional direction.

Common Bone Diseases

• Fractures: Broken bones.
• Osteoporosis: Loss of bone density.
• Osteomyelitis: Bone infection.
• Osteitis: Bone inflammation (e.g., Paget's disease).
• Acromegaly: Overgrowth of bones in face, hands, and feet.
• Fibrous dysplasia: Abnormal bone growth.
• Rickets: Vitamin D deficiency in children.
• Multiple myeloma: Cancer of plasma cells in bone marrow.
• Bone cancer: Cancers originating in bone or spreading to bone from other organs (e.g., osteosarcoma, breast cancer metastasis).

Test your knowledge of bone structure, composition, and types. Understand the differences between long, short, flat, sesamoid, and irregular bones, as well as the roles of various bone tissues. This quiz covers essential information on bone biology.