Bone Disorders

Question 1

What is osteoporosis?

Answer 1

Significant reduction in bone density

Question 2

What is the pathophysiology of osteoporosis?

Answer 2

Osteoclasts break down bone and osteoblasts remodel bone

In osteoporosis, the balance between remodelling and resorption is disrupted due to higher osteoclast activity

Question 3

What are some risk factors that can lead to osteoporosis?

Answer 3

-Age
-Low BMI, reduced mobility/activity
-Post menopause (oestrogen is a protective factor)
-Alcohol and smoking
-Low calcium or vitamin D
-Family history of fractures
-Long term steroids
-Chronic disease
-Certain meds like SSRIs, PPIs, anti-epileptics

Question 4

How is osteoporosis assessed?

Answer 4

T score of femoral neck via DEXA scan
(Measured in standard deviations away from avg healthy adult)

More than -1 = healthy
-1 to -2.5 = osteopenia
Less than -2.5 = osteoporosis
Less than -2.5 plus fracture = severe osteoporosis

Question 5

Who is recommended to get assessed for osteoporosis?

Answer 5

Long term corticosteroid users

All women 65+ and men 75+, or over 50s with risk factors

Question 6

What does the QFracture tool measure?

Answer 6

10 year risk of major fracture in osteoporosis

Offer DEXA scan if over 10%

Question 7

Management plan for osteoporosis

Answer 7

1- address risk factors (eg smoking, activity levels)
2- address calcium and vitamin D intake
3- medical management:
bisphosphonates (eg alendronate/risedronate weekly or zoledronic acid yearly)

Can also give monoclonal antibodies (-umab), hormone replacement therapy

Question 8

What is Paget’s disease?

Answer 8

Uncoordinated excessive bone turnover, eats to mixed density

Question 9

What causes Paget’s disease?

Answer 9

Unknown, but likely to be multifactoral
(genetics x environment)

Question 10

How does Paget’s disease present?

Answer 10

Commonly in old men

Can be asymptomatic
Bone pain and deformity
Fractures
Hearing loss
Compression neuropathy

Question 11

How is Paget’s disease investigated?

Answer 11

xray:
Bone enlargement and deformity
Cotton wool skull (poor patchy definition)
V shaped osteolytic defects in long bones
Osteoporosis circumscripta- (well defined osteolytic lesions)

blood test:
Raised ALP

Question 12

How is Paget’s disease managed?

Answer 12

bisphosphonates

Calcitonin as an alternative
Analgesia
Calcium and vitamin D

Question 13

What are some complications of Paget’s disease?

Answer 13

Hearing loss if ear bones affected
Hypervascularity -> heart failure
Osteosarcoma
Spinal stenosis and compression

Question 14

What is osteomyelitis?

Answer 14

Infection causing inflammation of bone and bone marrow

Question 15

What causes osteomyelitis?

Answer 15

Staph aureus is most common causative organism

Can be haematogenous or direct (ie open fracture or operation)

Question 16

What are the risk factors for osteomyelitis?

Answer 16

Open fractures
Surgery
Diabetes
PVD
IVDU
Immunosupression

Joint replacements can also become infected

Question 17

How does osteomyelitis present?

Answer 17

Random and systemic symptoms

Fever, pain and tenderness, erythema, swelling

Question 18

How is osteomyelitis investigated?

Answer 18

gold standard is MRI

Blood test shows raised inf. markers
Blood and bone cultures show causative organism

Question 19

How is osteomyelitis managed?

Answer 19

Surgical debridement

Antibiotics -> 6 wk flucloxacillin with 2 wk rifampicin

(Clindamycin for allergies and vancomycin for MRSA)

Question 20

What is the main possible complication of osteomyelitis?

Answer 20

Chronic osteomyelitis- requires 3 more months of antibiotics

Question 21

What is osteomalacia?

Answer 21

Abnormal softening of the bone

Question 22

What causes osteomalacia?

Answer 22

Vitamin D deficiency
Hypophosphataemia
Re feeding syndrome
Alcohol (affects phosphate absorption)
Malabsorption
Long term anticonvulsants
CKD

Question 23

How does vitamin D affect osteomalacia pathology?

Answer 23

Vit D needed for calcium absorption and osteoblastic activity
If deficient it leads to hypocalcemia and high PTH
This leads to higher osteoclastic activity and more absorption, impairing mineralisation of newly formed osteoid

Leads to weak bone

Question 24

How does osteomalacia present?

Answer 24

waddling gait

-Bone pain in pelvis, spine, and femora
-Hypocalcaemia symptoms (cramps, irritability, fatigue, seizures, brittle nails)
-easy fracture

Deformity
Proximal myopathy
Dental defects

Question 25

How is osteomalacia investigated?

Answer 25

X-ray- pseudofractures (loosers zones) in pubic rami, proximal femora, ulna, ribs

Bloods show low calcium and phosphate, and high ALP

Question 26

How is osteomalacia treated?

Answer 26

Vitamin D therapy with calcium and phosphate supplementation-
D3 tablets, calcitrol, alfacalcidol

Monitor CKD patients as they may be unable to convert vitamin D to calcitrol

Question 27

What is osteogenesis imperfecta?

Answer 27

Brittle bone disease

Question 28

What causes osteogenesis imperfecta?

Answer 28

Many genetic mutations that affect collagen formation

Question 29

How does osteogenesis imperfecta present?

Answer 29

recurrent fractures with bone pain
blue/grey sclera- hallmark feature
Hypermobility
Early deafness

Deformities:
Dental formation issues
Triangle face
Short stature
Bowed legs
Scoliosis

Question 30

How is osteogenesis imperfecta diagnosed?

Answer 30

Clinical diagnosis based on signs

Question 31

How is osteogenesis imperfecta managed?

Answer 31

Bisphosphonates and vitamin D supplements

MDT -> physio, occ health, social workers