Bone diseases

Question 1

What are the two necrotising bone diseases we need to know?

Answer 1

Osteochondritis 
Avascular Necrosis (AVN)

Question 2

What is osteochondritis?

Answer 2

Inflammation of bone/cartilage due to interrupted blood supply leading to necrosis.

Question 3

What causes the interrupted blood supply in osteochondritis?

Answer 3

Repeated movement or traction injury compressing blood vessels.

Question 4

What are some of the signs osteochondritis can cause?

Answer 4

Compression and fragmentation of bone (osteochondritis dissecans)
Separation from periosteum
Pain

Question 5

What are the common sites for osteochondritis to present?

Answer 5

2nd metatarsal 
Navicular
Lunate
Capitellum of elbow
Perthes disease in hip
Often occurs at apophysis (where tendons attach)

Question 6

How do you treat osteochondritis?

Answer 6

Pin
Osteotomy
Remove fragments

Question 7

What group is most affected by osteochondritis?

Answer 7

Children

Question 8

What is avascular necrosis?

Answer 8

Ischemic necrosis of bone

Question 9

What are the common sites to find avascular necrosis?

Answer 9

Femoral head and condyles, head of humerus, capitellum, scaphoid, talus

Question 10

What are common causes of avascular necrosis?

Answer 10

Idiopathic, fractures, thrombophilia, sickle cell, SLE, decompression sickness, alcohol, steroids, hyperlipidemia (last 3 due to fat sludging up vessels)

Question 11

How do you diagnose and treat avascular necrosis?

Answer 11

Early- MRI and decompress bone

Late- Damage done therefore replace.

Question 12

What are the five biochemical diseases of bone we need to know?

Answer 12

Osteoporosis
Osteomalacia and Rickets
Hyperparathyroidism
Renal Dystrophy
Paget's Disease

Question 13

What is osteoporosis?

Answer 13

Decreased bone mineral density and increased porosi weakens bone.
2.5 standard deviations less than mean peak for race and sex.
Occurs naturally as part of aging.

Question 14

What is osteopenia?

Answer 14

A milder form of osteoporosis. 1-2.5 deviations left.

Question 15

What are the two types of osteoporosis?

Answer 15

Type 1- Post menopausal

Type 2- Occurs due to aging

Question 16

What are some risk factors for developing osteoporosis?

Answer 16

Smoking, alcohol, poor diet, inactivity, lack of VD.

Question 17

How do you diagnose osteoporosis?

Answer 17

DEXA scanning for bone density.

Serum Ca and P must be normal.

Question 18

How do you treat osteoporosis?

Answer 18

Cannot restore bone density but Ca and VD supplements, bisphosphonates, denosumab and strontium can slow the disease.

Question 19

What is osteomalacia and rickets?

Answer 19

Softening of bone cue to lack of Ca and P.

Question 20

What age group is osteomalacia found in?

Answer 20

Adults

Question 21

What age group is rickets found in?

Answer 21

Children

Question 22

What causes osteomalacia/rickets?

Answer 22

Lack of dietary Ca, insufficient VD or P loss due to kidney disease (refeeding syndrome, alcohol, anticonvulsants)

Question 23

What are the symptoms of osteomalacia/rickets?

Answer 23

Bone pain, deformities, multiple fractures, hypocalcemia, (muscle cramps, fatigue, brittle nails), abnormal blood chemistry (decreased Ca and P, increased ALP)

Question 24

What is the treatment for osteomalacia/rickets?

Answer 24

VD therapy and Ca/P supplements

Question 25

What is hyperparathyroidism?

Answer 25

Overactive parathyroid glands produce increased PTH.

Question 26

What are the three forms of Hyperparathyroidism?

Answer 26

Primary- Benign adenoma or hyperplastic disorder Secondary- Physiological over production due to hypocalcemia Tertiary- Chronic secondary who develop adenoma.

Question 27

How does hyperparathyroidism present?

Answer 27

Fatigue, depression, bone pain, thirst, renal stones, fragine bones and lytic lesions.

Question 28

How do you diagnose hyperparathyroidism?

Answer 28

Increased serum PTH and Ca. Low or normal P.

Question 29

How do you treat hyperparathyroidism?

Answer 29

Remove adenomatous gland and treat underlying cause.

Question 30

What is renal dystrophy?

Answer 30

CKD -> Decrease P excretion and VD activation -> Secondary HPTism -> Osteomalacia.

Question 31

What is Paget's Disease?

Answer 31

Excessive osteoclast activity leads to increased bone turnover which doesn't remodel.

Question 32

What causes Paget's Disease?

Answer 32

Viral infection and genetics.

Question 33

What bones are commonly affected by Paget's Disease?

Answer 33

Pelvis, femur, skull, tibia and ear ossicles.

Question 34

What does Paget's disease do to bone?

Answer 34

Thickened, brittle and misshapen bones.

Question 35

How does Paget's disease present?

Answer 35

Can be asymptomatic or cause arthritis, fractures, deformities, pain and cardiac failure.

Question 36

What age group does Paget's Disease usually affect?

Answer 36

50-70 YO

Question 37

How do you detect Paget's Disease?

Answer 37

Increased serum ALP, normal serum Ca and P. XR

Question 38

How do you treat Paget's Disease?

Answer 38

Bisphosphonates or calcitonin. Joint replacement and fracture repair.