1) Bone Composition, Classification, Growth and Healing

Which of the following best defines a bone according to the lecture?

A dynamic composite of specialized connective tissue made of cells and matrix

What is the inorganic component of bone primarily composed of?

Calcium and other minerals

Why can bone be considered an organ?

It contains multiple tissue types performing specific functions

Which of the following is NOT one of the tissue types found in bone?

Lymphatic muscle

What is the major function of bone related to minerals?

Calcium reservoir

Which of the following is NOT an anatomical classification of bones?

Tubular

Where is the growth plate (physis) actually located in children?

. Epiphysis

Which statement about cortical bone is true?

It is dense, strong, and forms the outer layer

What is the inner part of the bone called

Cancellous

What is the basic functional unit of bone?

Osteon

What is found at the centre of an osteon?

Haversian canal

What is the function of osteoblasts?

Build and lay down new bone matrix

Which of the following is true about cancellous bone?

Found at metaphysis and epiphysis, with honeycomb-like structure

What is special about the perioseal layer in children

Very Thick

Which part of bone has higher turnover rate?

Cancellous bone in metaphysis

In elderly patients with osteoporosis, fractures are more likely to occur in:

Metaphysis or epiphysis due to porous structure

Which description of woven bone is correct?

Laid down irregularly and seen in healing fractures

Which of the following statements about woven bone is FALSE?

It is stronger than lamellar bone in mature adults

Lamellar bone differs from woven bone in that it:

Has regular, parallel arrangement and lower cell activity

What is the term for the process of bone development from cartilage?

Endochondral ossification

Where does endochondral ossification occur?

At growth plates and during fracture healing

Which of the following is associated with intramembranous ossification?

Direct bone development without cartilage template

What is a common radiographic sign of secondary bone healing?

Cloudy callus formation bridging fracture site

What do canaliculi connect in the osteon system?

Osteocytes to Haversian canals

Which of the following best describes the role of osteoclasts?

Resorb and break down bone tissue

Which zone in the growth plate is associated with the beginning of calcium deposition?

Zone of provisional calcification

What marks the first step in embryonic bone formation?

Mesenchymal cell commitment

What distinguishes intramembranous ossification from endochondral ossification?

Occurs without a cartilage model

Primary bone healing requires which of the following conditions?

Rigid fixation with minimal gap

What is the term for material that serves as a scaffold for bone cells to grow on?

Osteoconductive

What is true about osteoinductive materials?

They induce progenitor cell differentiation via growth factors

According to Giannoudis’ diamond concept, which of the following is essential for bone healing?

Vascularity

What does a strain of around 10% at a fracture site allow?

Endochondral ossification

Which of the following is TRUE about strain in bone healing?

Moderate strain enables cartilage formation

What is the correct order of events in secondary bone healing?

Bleeding → Granulation → Cartilage → Bone

In primary bone healing, which cells are first to lead the cutting cone?

Osteoclasts

What defines a non-union fracture?

Fracture fails to heal in expected time frame

What does Wolff’s law state?

Bone remodels in response to mechanical stress

Which electrical charge results from bone compression and promotes bone formation?

Electronegative, attracting osteoblasts

What happens to bone density in immobilized limbs over time?

Density decreases due to Wolff’s Law

hich hormone activates osteoclasts to increase serum calcium?

Parathyroid hormone

What bone disease is caused by vitamin D deficiency in adults?

Osteomalacia

What bone disease is caused by vitamin D deficiency in kids

Rickets

What is a hallmark symptom of rickets in children?

Bowed legs

What is the primary role of oestrogen in bone metabolism?

Blocks osteoclast activity

Corticosteroids negatively affect bone by:

Inhibiting bone formation and causing resorption

Osteoporosis is best defined as:

Decreased bone mineral density

How does the World Health Organization define osteoporosis?

A skeletal disease marked by low bone mass and deteriorating bone microarchitecture

What type of fractures are typical in patients with osteoporosis?

Fractures from low-trauma incidents like minor falls

What does a DEXA scan primarily measure?

The bone mineral density compared to a healthy young adult

What T-score value range defines osteopenia?

1-2.5 SDs away from normal

Which bones are typically scanned during a DEXA assessment?

Lumbar spine and proximal femur

Which of the following is NOT a listed risk factor for osteoporosis in the text?

Obesity

What lifestyle principle explains how force applied to bones can increase bone density?

Wolff’s Law

How does smoking negatively affect bone health?

It destroys osteoblasts needed for bone remodeling

What is one reason alcohol contributes to osteoporosis?

It interferes with vitamin D absorption and liver hydroxylation

What supplement is commonly given to patients at risk of osteoporosis?

ADcal D3 containing calcium and vitamin D

Which drug is most commonly prescribed first-line for osteoporosis, according to NICE guidelines?

Alendronate

What is a significant drawback of long-term bisphosphonate use?

Sclerotic, abnormally thick bone that may fracture

How often is a typical dose of alendronate administered?

Once a week

Which statement is TRUE regarding hormone replacement therapy (HRT) and osteoporosis?

HRT is not considered a pharmacological treatment option for osteoporosis

Which statement is TRUE regarding hormone replacement therapy (HRT) and osteoporosis?

HRT is the preferred pharmacological treatment for osteoporosis