Bone, bone disorders and arthritis

Question 1

What does connective tissue consist of?

Answer 1

Cells, fibres and gel-like substance

Question 2

what is a matrix?

Answer 2

material in between the cells

Question 3

What are the organic components of bone?

Answer 3

cells - osteoblasts, osteocytes and osteoid

Question 4

what is the function of bone?

Answer 4

provide support, structure and protect organs
mineral storage, fat storage, hormone production and blood cell formation (which occurs in the blood marrow)

Question 5

Typically, what are the open spaces of bone filled with?

Answer 5

Bone marrow

Question 6

Where are osteogenic cells found?

Answer 6

In the periosteum and endosteum

Question 7

HiWhy is bone remodelling so important?

Answer 7

bone is constantly exposed to insults and also for regulation of metabolic processes (for release or absorption of ions)

Question 8

What is the origin of osteoclasts?

Answer 8

WBC lineage (mostly monocytes and macrophages)

Question 9

Which chemical messengers are associated with bone resorption (eg: when calcium levels are low)

Answer 9

PTH, vitatmin D

Question 10

Which chemical messengers are associated with bone formation? (eg: when calcium levels are high)

Answer 10

Oestrogen / calcitonin

Question 11

Is inflammation associated with bone resorption or bone formation?

Answer 11

Bone resorption

Question 12

What happens to the bone if there is a deficiency of vitamin D?

Answer 12

failure of osteoid to mineralise (kicks off transcription genes which cause mineralisation of newly secreted bone)
(low levels of vitamin D encourage bone resorption to increase amount of free calcium)

Question 13

What is the cause of primary hyperparathyroidism?

Answer 13

adenoma of one of the parathyroid glands

Question 14

What does hyperparathyroidism do to levels of PTH and bone?

Answer 14

High PTH levels trigger the bones to release more calcium than normal into the blood. The loss of calcium from the bones may weaken them

Question 15

What is the cause of secondary hyperparathyroidism?

Answer 15

chronic renal disease
you get calcinuria (calcium salts in urine)
so to compensate this PTH&raquo_space;

Question 16

What is a brown tumour or giant cell granuloma?

Answer 16

A mass formed where a bone lesion arises in an area of high osteoclast activity

Question 17

In the early inflammatory stage of bone healing, what is formed at the fracture site? Why is the formation of this so important?

Answer 17

Haematoma - it supplies the stem/growth cells required for healing

Question 18

What does the granulation tissue turn into in the repair stage of bone healing?

Answer 18

Callus

Question 19

What is the process called that turns primary callus into secondary callus? (soft callus - cartilage –> hard callus - woven bone)

Answer 19

endochondral ossification

Question 20

What can happen if the fracture site is not adequately immobilised?

Answer 20

A fibrous union may form in place of solid bone formation (there will be degree of permanent mobility)

Question 21

What factors can impact fracture healing?

Answer 21

blood supply to the fracture site
infections
underlying bone pathologies
whether fracture is closed/compounbd
co-morbid conditions (DB, use of long term corticosteroids, previous radiotherapy at site)
use of cox-2-inhibitors

Question 22

What are some of the clinical presenations of osteogenesis imperfect “brittle bone disease”?

Answer 22

blue sclera
deafness
> risk of fracture
shortened appearance
class 3 skeletal

Question 23

What is osteopetrosis?

Answer 23

decreased osteoclastic activity (osteoclasts fail to resorb bone)

Question 24

Why is the bone brittle in osteogenesis imperfecta?

Answer 24

lack of organic component (collagen)

Question 25

What T-score would indicate osteoporosis?

Answer 25

-2.5 or less

Question 26

Why is osteoporosis a normal part of the aging process?

Answer 26

Bone density declines as we get older (as oestrogen is in short supply in post-menopausal and androgen levels fall in men)

Question 27

What medication can be given to patients with osteoporosis to prevent bone loss?

Answer 27

Vitamin D/calcium
BISPHOSPHONATES

Question 28

What medication can be given to patients with osteoporosis to prevent bone loss?

Answer 28

• Vitamin D/calcium
• BISPHOSPHONATES
• alendronic acid, ibandronic acid, risedronate, zolendronic acid)
• SERMs (selective estrogen receptor modulator) eg: raloxifene (similar action as endogenous ostrogen)
• HRT - but primarily for symptoms of menopause

Question 29

How is osteoporosis managed?

Answer 29

• Education
• Physiotherapy
• Physical aids
• Active fall prevention
• Surgery

Question 30

What is Paget’s disease?

Answer 30

Disorder of bone turnover/remodelling

Question 31

What treatments can be used in Paget’s?

Answer 31

BISPHOSPHONATES!

Question 32

what implications can bisphosphonates cause in dental tx?

Answer 32

BRONJ - impairs bony healing

Question 33

What is osteoarthritis?

Answer 33

progressive erosion (degeneration) of articular cartilage

Question 34

Over time, what can happen to the bone in osteoarthritis?

Answer 34

it becomes exposed and damaged leading to cysts and abnormal growth (osteophytes) –> inflammation

Question 35

What joints are typically affected in osteoarthritis?

Answer 35

Weight-bearing joints (hips/knees)

Question 36

What are some of the signs of osteoarthritis?

Answer 36

Signs: crepitus, restricted movement, bony enlargement

Question 37

What are some of the symptoms of osteoarthritis

Answer 37

pain and functional limitation

Question 38

What is the most characteristic feature of osteoarthritis ?

Answer 38

Narrowing joint space

Question 39

What type of nodes are commonly seen in long term osteoarthritis?

Answer 39

Heberden’s nodes

Question 40

How is osteoarthritis managed?

Answer 40

Education
Weight loss
Physiotherapy
Analgesia (topical NSAIDs_
Intra articular corticosteroid for single painful joints
Intramuscular corticosteroid for widespread arthritis
Surgery

Question 41

What is rheumatoid arthritis?

Answer 41

Multi-system inflammatory condition - autoimmune condition

Question 42

Does RA typically affect younger or older patients?

Answer 42

Younger pts

Question 43

What are the signs you will typically see in RA? (signs of inflammation)

Answer 43

calor, dalor, rubor, tumor, functio laesi
- heat, pain, redness, swelling, loss of function

Question 44

Which feature is highly indicative of RA?

Answer 44

early morning stiffness

Question 45

What is ankylosing spondylitis? Is it more common in male or female? Is there a genetic predisposition?

Answer 45

chronic inflammatory arthritis, more common in male, genetic predisposition for those with certain tissue types (HLA-B27) - you may see families where father and son are affected

Question 46

What considerations should be given for patients with ankylosing spondylitis?

Answer 46

• Require neck support / pillows
• Shorter appts
• May have profound immunosuppression due to long-term corticosteroid use

Question 47

What area of the body is more affected in patients with ankylosing spondylitis?

Answer 47

The spine