Bone Pathology

Question 1

Four Features of Osteoarthritis

Answer 1

1. Non uniform cartilage damage, 2. sub-chondral damage, 3.osteophytes 4. reduced joint space

Question 2

Four features of Rheumatoid Arthritis

Answer 2

1. Inflammation of synovium (Lymphocytes, Plasma cells and Germinal centres, 2. Villus Hyperplasia of the synovium 3. Aggressive Pannus that invades cartilage and bones 4. Repair of bone via fibrosis leads to fusion of joint.

Question 3

What are the 3 stages of bone healing

Answer 3

3 stages - Inflammation, healing and remodelling

Question 4

What are the structural features of bone repair

Answer 4

Fracture, soft callus, hard callus and bone

Question 5

Four Features of Gout

Answer 5

• Epitheloid macrophages
• Fibrosis
• Multinuclear giant cells
• Central Urate deposits

Question 6

What are the normal structures of a joint

Answer 6

• Articular cartilage (Collagen II)
• Synovial Fluid
• Synovial membrane
• Joint space
• Capsule and supporting ligaments

Question 7

What cells comprise the synovial membrane

Answer 7

type A Macrophage

Type B Fibroblasts

Question 8

Drugs to treat bone pathology

Answer 8

Allopurinal, bisphosphates, estrogen agonists, supplements, RANKL inhibitors

Question 9

WHat is the RANKL inhibitor

Answer 9

Denosumab

Question 10

What is estrogen agonist

Answer 10

Raloxifen

Question 11

What does allopurinal treat

Answer 11

Gout

Question 12

How do bisphosphates work

Answer 12

Incorporated into cortical bone and when osteoclasts break down the bone they eat the bisphophates and are killed

Question 13

What are supplments given to treat bone pathology

Answer 13

Calcium and vitamin D

Question 14

What are the two surfaces of the bone

Answer 14

Endosteum and periosteum

Question 15

WHat is the function of the Endosteum and periosteum

Answer 15

Is a thin layer of CT and cells that line the inside and the outside of the bone. In this layer are the precursor cells such as osteocytes, osteoblasts and osteoclasts. Is absent where muscles, tendons or ligaments attach to bone

Question 16

What are the two different scaffolds that are used to manifacture bone

Answer 16

Membrane and endochondrial scaffolds

Question 17

What bones arise from the Membrane

Answer 17

From mesenchymal origin and will forms the flat bones of the face, clavicle and mandible

Question 18

What bones arise from endocondrial scaffolds

Answer 18

Most of the bones and the cartilage is replaced with bone. This can continue throughout life and some bones do not form until later in life (10 years of age)

Question 19

What are the 6 regions of bone formation at the epiphysial

Answer 19

• Resting
  - Prolifferation with chondrocytes
  - Maturation
  - Hypertrophic
  - Ossification
  - degeneration

Question 20

What are the features of wooven and lamella bone

Answer 20

Woven bone is the phase of healing after a fracture, it has, more cells, more collagen and no Haversian systems

Question 21

What are the two macroscopic appearances of hyaline cartilage

Answer 21

ECM and hyaline

Question 22

What are the main components of ECM of hyaline cartilage

Answer 22

• Collagen II
  
  • Hyaluronic acid produced by the chrondrocytes
  • Proteoglycans such as aggrecan
  • Glycosaminoglycans such as chondroitin sulfate
    
    • Water (70%)

Question 23

What is synovial fluid composed of

Answer 23

Synovial fluid is a filtrate of plasma fluid from the many capillaries of the synovium, enriched with lubricating substances such as hyaluronic acid.