Chronic conditions

Question 1

WHO definition of osteoporosis?

Answer 1

Bone mineral density T >-2.5 SD below the mean seen in peak bone mass of young (25-30) normal subjects

Question 2

Factors of osteoporosis?

Answer 2

PTH
Vit D
Calcitonin
Estrogen
Glucocorticoids

Question 3

How to classify osteoporosis?

Answer 3

Generalized vs localized
Primary vs Secondary [Congenital vs Acquired]

Question 4

Primary osteoporosis types?

Answer 4

• Age-related, post-menopausal
• Mayo Clinic Classification

Question 5

Mayo Clinic classification of primary osteoporosis?

Answer 5

Type 1 = post-menopausal women - wrist, vertebral crush
Type 2 = Age-related. Hip, vertebral wedge

Question 6

Secondary osteoporosis types?

Answer 6

Congenital - Osteogenesis imperfecta, Ehler Danlos, Marfan’s, glycogen storage disorders, hypophosphatasia

Question 7

What is wedge fracture characterized by?

Answer 7

Loss of height, mostly of anterior vertebral body, causing wedge-shaped vertebra

Question 8

OSTA formula?

For osteoporosis

Answer 8

Age (years) - weight (kg)

Question 9

How to use OSTA?

Answer 9

20 and above = high risk. Measure BMD
0-19 = Moderate risk. Check BMD if other RF
<0 = Low risk. Check BMD if there is hx of fragility fractures

Check BMD with DEXA

Question 10

How do cellulitis and nec fasc spread?

Answer 10

Along soft tissue and fascial planes

Question 11

Primary Mx for Nec fasc?

Primary survery ABC

Answer 11

2 large bore IV cannula + fluid resuscitation

Question 12

Operative approach to septic arthritis?

Answer 12

IV Abx, operative irrigation and drainage of joint

Question 13

Why is septic arthritis an orthopaedic emergency?

Answer 13

Irreversible joint damage -> severe cartilage destruction occur in 8 hrs
Mortality higher in elderly a/w comorbids

Question 14

Common sites for septic arthritis

Answer 14

Knee
Hip
Elbow
Shoulder

Question 15

Does OM progress to Septic arthritis in kids but not in adults?

Answer 15

Yes. Physis is closed and there is no blood supply in adults. Hence infection stays in bone and does not spread to joint

Question 16

Types of Periprosthetic joint infection?

Answer 16

Acute PJI within 3-6 weeks = no biofilm formed. Can preserve implant
Chronic >6 wks = biofilm formed and seals off infection, preventing immune system from acting on bacteria. Implant must be removed.

biofilm created by all bacteria forms on implant in 4 weeks

Question 16

Radiograph findings for PJI?

Answer 16

Periosteal reaction
Scattered patches of osteolysis
Bone resorption without implant wear
Transcortical sinus tracts
Implant loosening

Question 17

What is rickets?

Answer 17

metabolic bone disease caused by a defective mineralization of osteoid matrix caused by inadequate calcium and phosphate that occurs prior to closure of the physes

Vitamin D and PTH play an important role in calcium homeostasis.
calcium/phosphate homeostasis is disrupted

Question 18

Clinical presentation of rickets?

Answer 18

Brittle bones
Ligamentous laxity
Bowing of long bones
Enlargement of costal cartilage

Question 19

PE of rickets?

Answer 19

Genu varum
Waddling gait
Tibial bowing
Dorsal kyphosis

Question 20

In OA, how do osteophytes and sclerosis present on XR?

Answer 20

Sclerosis is thicker white on edge of bone.
Osteophytes and sclerosis come together.

Question 21

XR findings of OA?

Answer 21

Subchondral cysts
Narrowing of joint space
Subchondral sclerosis
Osteophytes