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Flashcards in Biochem disorders of bone Deck (47):
1

Give examples of bisphosphonates

Alendronate
Risedronate
Etidronate

2

What is desunomab

Monoclonal antibody which reduces osteoclastic activity

3

What does strontium do?

Increases osteoblast replication and reduces resorption

4

What is Zoledronic acid?

Once yearly IV bisphosphpnate (but v expensive)

5

Risks of HRT

Inreased breast and endometrial cancer rates
DVT

6

Risks of Raloxifene (oestrogen receptor modulator)

DVT

7

Qualitive defect of bone

Osteomalacia
-due to deficient mineralisation of osteoid
-INADEQUATE AMOUNTS OF CALCIUM AND PHOSPHATE

8

Psuedofractures (Looser's zones)

Osteomalacia

9

Patients may complain of bone pain, have deformities of soft bones, sustain pathological fractures easily and have symptoms of hypocalcemia

Osteomalacia

10

Low calcium
Low phosphate
High serum alk phos

Osteomalacia

11

Blood biochem in osteoporosis

Normal

12

Brown tumours

Caused by hyperparathyroidism (lytic lesions in bone)

13

Osteitis fibrosa cystica

Caused by hyperparathyroidism

14

Treatment for high serum calcium

EMERGENCY
IV fluids
Bisphosphonates
Calcitonin

15

Treatment of hyperparathyroidism

Removal of adenomatous glands
Treatment of underlying cause (vitamin D supplementation)
Emergency treatment for very high calcium

16

What is renal osteodystrophy

Typical bone changes due to CKD
(reduced phosphate excretion and inactive activation of vitamin D --> sclerosis of bones and calcification of soft tissues)

17

Type 1 osteoporosis

Post menopausal
Colles fracture and vertebral insufficiency fracture most likely

18

Type 2 osteoporosis

Osteoporosis of old age
Fracture of vertebra and femoral neck most common

19

Causes of hypophosphatemia

Refeeding syndrome
Alcohol excess

20

Principal cause of osteomalacia

Insufficienct calcium from the intestine because of lack of dietary calcium or a deficiency of or resistance to the action of vitamin D, or phosphate deficiency caused by increased renal losses

21

Drugs associated with poor bone quality

Long term anticonvulsant use

22

Treatment for pagets

Bisphosphonates (inhibit osteoclasts) or calcitonin if extensive lytic disease

23

Defect of which type of collagen in osteogenesis imperfecta?

Type 1

24

Osteogenesis imperfecta method of inheritence

Autosomal dominant

25

Blue sclera and loss of hearing

Osteogenesis imperfecta

26

Sofield procedure

Multiple osteotomies and intramedullary stabilisation for progressive deformity caused by OSTEOGENESIS IMPERFECTA

27

Prominent forehead widened nose
Lax joints
Normal mental development

Achondroplasia

28

Marfan inheritence

Autosomal dominant

29

Tall stature, disproportionately long limbs and ligamentous laxity
High arched paalte
Scoliosis
Pectus excavatum
Eye problems (lens dislocation, retinal detachment)
Aortic aneurysm
Cardiac valve incompetence

Marfan syndrome

30

Which dislocation common in Down syndrome?

Patella
Atlanto-axial instability in the C-spine

31

Profound joint hypermobility, vascular fragility with ease of bruising, joint instability and scoliosis

Ehlers Danlos
(autosomal dominant)

32

Diagnosis is by raised serum creatinine phosphokinase and abnormalities on muscle biopsy

Duchenne muscular dystrophy

33

Hypoplastic bones

Short

34

If you have limb malformations caused in gestation, when would they have occurred?

between 4th and 6th week of gestation

35

What is syndactyly?

COMMONEST congenital malformation
-two digits are fused
(usually separated age 3/4)

36

Polydactyly

Extra digit

37

Fibular hemimelia

Absence of fibula
-leads to shortened limb
-bowing of tibia
-ankle deformity

38

Most common congenital fusion

Tarsal coalition

39

Erbs palsy

Damage to C5 and C6 during pregnancy
(loss of motor innervation of the deltoid, supraspinatus, infraspinatus, biceps and brachialis)

40

What does erbs palsy look like

Humerus is internally rotated (unopposed subscapularis)
"waiter's tip posture"
Physiotherapy
Prognosis good

41

What is Klumpe's palsy?

Lower brachial plexus palsy (C8 and T1)
Paralysis of intrinsic hand muscles +/- wrist flexors an POSSIBLE horner's syndrome
Fingers typically flexed
(hand looks a bit like spider man but not quite)
No specific treatment
Prognosis poor

42

Babinski sign

UMN

43

Drugs which can help reduce spacticity

Baclofen
Botox

44

Meningocele

This is in spina bifida
--> menignocele not usually associated with neurological sequelae

45

Myelomeningocele

Usually has neurological deficit

46

Spina bifida and the feet

Can cause high arched foot!!!

47

A viral infection affecting motor anterior horn cells in the spinal cord or brainstem resulting in a lower motor neurone deficit

Polio