Osteoporosis

Question 1

osteocytes

Answer 1

sitting in lacunae, bone cells responsible for the maintenance of the bony matrix

Question 2

lacunae

Answer 2

a cavity or depression (in bone)

Question 3

osteoclasts

Answer 3

specialized cells that breakdown damaged bone tissue.

Question 4

osteoblasts

Answer 4

specialized cell that help to form new bones and bone growth

Question 5

fibroblasts

Answer 5

a cell that contributes to the formation of CT

Question 6

Radical canaliculi

Answer 6

connect the Haversian canal to the lacunae

Question 7

osteoporosis

Answer 7

A metabolic bone disorder characterised by a significant loss of bone mineral density (BMD) and a loss of microstructure

Question 8

what is important to remember about osteoporosis?

Answer 8

There is a PROPORTIONAL loss of the organic and inorganic components of bone tissue. This means that the mineral to collagen ratio is within the reference range.

Question 9

aetiology of osteoporosis

Answer 9

comes with age but is most prevalent in females, especially after going through menopause, due to the decrease in oestrogens and androgens, 1 in 2 women experience osteoporosis

Question 10

idiopathic osteoporosis

Answer 10

occurs in children and young adults. Reasons are unknown

Question 11

Oestrogen deficiency (type 1 osteo)

Answer 11

increase both bone resorption and formation, however osteoblasts are unable to keep up with osteoclasts. decreased estrogen leads to an increased secretion of inflammatory cytokines, increasing osteoclast recruitment and activity.

Question 12

signs and symptoms of osteoporosis

Answer 12

• fractures, loss of height, stooped posture (kyphosis)

Question 13

Kyphosis due to compression fracture of the vertebral bodies

Answer 13

• decreased respiratory function
• pinched nerves
• increased likelihood of fails
• immobilisation
• DVT and consequent embolisation
• Bed sores and infections
• Muscle atrophy
• death

Question 14

DEXA scan

Answer 14

dual-energy x-ray absorptiometry scanning measures bone density in the hip, vertebrae and forearm

Question 15

T-score

Answer 15

results of the DEXA which compares to young, healthy population

Question 16

normal T-score

Answer 16

-1.0 or higher

Question 17

osteopenia T-score (low bone density but not quite osteoporosis)

Answer 17

between -1.0 and -2.5

Question 18

osteoporosis T-score

Answer 18

-2.5 or lower

Question 19

prevention osteoporosis

Answer 19

• smoking cessation
• reduction of alcohol intake
• proper intake of calcium and vitamin D
• Low impact, weight-bearing exercises

Question 20

How can a vitamin D deficiency increase the risk of osteoporosis?

Answer 20

Calcium can not properly be absorbed from the intestines, this increases release of parathyroid hormone (PTH), increasing the activity of osteoclasts

Question 21

fracture

Answer 21

a medical condition where the continuity of the bone is broken, when a force applied exceeds the tensile or compressive strength of a bone

Question 22

traumatic bone fracture

Answer 22

the bone is healthy but cannot withstand the force applied

Question 23

pathological bone fracture

Answer 23

the bone is weakened by an underlying condition, and it snaps/breaks even when the trauma would not justify it.

Question 24

incomplete fracture

Answer 24

the bone is damaged but still in one piece , hence its closed

Question 25

greenstick fracture

Answer 25

an incomplete fracture in which the fracture disrupts the outer surface of the bone bun leaves the inner surface intact

Question 26

depressed fracture

Answer 26

a bone fragment is depressed below the normal surface, often occurs in the skull.

Question 27

most common manifestations of fracture

Answer 27

pain, impaired sensory function, swelling, bleeding, movement may be restricted

Question 28

Reduction

Answer 28

realignment of broken ends

Question 29

immobilisation

Answer 29

promotes bone healing typically 6-8 weeks

Question 30

Steps in bone healing/formation

Answer 30

1. Haematoma formation
2. Soft callus formation (fibrocartilaginous)
3. Hard callus formation (ossification)
4. Bone remodelling

Question 31

Haematoma formation

Answer 31

torn blood vessels haemorrhage and a haematoma forms at the fracture site. A band of necrotic tissue forms widening the fracture gap. inflammation occurs

Question 32

fibrocartilaginous callus

Answer 32

new CT forms and extends into the haematoma, filling the gap created by the necrotic tissue. Deposition of collagen and fibrocartilage into a soft callus

Question 33

Ossification

Answer 33

As the result of calcium deposition, the soft callus converts to a bony hard callus. Bony callus begins to form 3-4 weeks arfter injury and continues until 2-3months

Question 35

Bone remodelling

Answer 35

compact bone is laid down to reconstruct shaft walls. Excess material on the bone shaft exterior and within the medullary cavity is removed by osteoclasts

Question 36

posttraumatic osteomyelitis

Answer 36

bacterial infestation of the bone marrow. can spread to the bone and periosteum

Question 37

other complications of fracture

Answer 37

• nerve damage
• blood vessel damage
• thrombosis
• delayed bone healing and malunion
• non-union (pseudoarthrosis)