MUSCULOSKELETAL

Question 1

What is the physiological response of bone to injury?

Answer 1

A: Increased turnover, which can be imaged with bone-seeking radiotracers.

Question 2

What is the most common bone-seeking radiotracer used in South Africa?

Answer 2

A: 99mTc Methylene Diphosphonate (MDP).

Question 3

Which PET agent is used for bone imaging?
A: 18F Sodium Fluoride (18F NaF).

Answer 3

Which PET agent is used for bone imaging?
A: 18F Sodium Fluoride (18F NaF).

Question 4

: What processes increase during bone remodeling?

Answer 4

:

Increased blood flow.
Increased extraction of ions onto the bone.
Increased binding of ions to hydroxyapatite crystals.

Question 5

What are the conditions in which 99mTc MDP is commonly used?
A

Answer 5

Osteoblastic bone metastases.
Osteomyelitis.

Question 6

Name a radiotracer specific for bone infection imaging.

Answer 6

A: 99mTc-labeled white blood cells.

Question 7

Why can inflammatory and cancer cells be imaged using 18F FDG?
.

Answer 7

A: Because they have a high number of glucose transporters and increased hexokinase activity.

Question 8

What are the four methods of tumor cell transport to the bone?

Answer 8

Hematogenous route (venous or arterial).
Lymphatic route.
Direct spread (e.g., sternum in breast cancer).
Intra-spinal route.

Question 9

Which route is most common for hematogenous spread of bone metastases?

Answer 9

A: Venous route through Batson’s vertebral plexus.

Question 10

What are the characteristics of Batson’s vertebral plexus?

Answer 10

Thin-walled veins.
Low intraluminal pressure.
Valveless veins.
Intercommunicating system.

Question 11

What are the patterns of bone response to metastases?

Answer 11

Bone resorption (increased osteoclastic activity or tumor destruction).
Bone formation (reactive).

Question 12

What are the types of bone metastases?

Answer 12

Osteolytic (e.g., renal, adrenal, acute leukemias).
Osteoblastic (e.g., prostate, neuroblastoma).
Mixed (e.g., lung, breast cancer).

Question 13

Where does osteomyelitis commonly occur, and why?

Answer 13

A: In the metaphysis of long bones due to:

Rich and sluggish blood flow.
Porous bone structure.

Question 14

: What is sequestrum in osteomyelitis?

Answer 14

A: Necrotic bone formed when blood supply to the bone is impaired.

Question 15

What is involucrum in osteomyelitis?

Answer 15

A: New bone formed around the infection.

Question 16

How is non-violated bone osteomyelitis diagnosed in nuclear medicine?

Answer 16

A: Using a 3-phase bone scan (flow, blood pool, and delayed imaging).

Question 17

How is violated bone osteomyelitis diagnosed in nuclear medicine?

Answer 17

A: Using 99mTc-labeled white cell imaging.

Question 18

How can septic and aseptic loosening of prosthetic joints be differentiated?

Answer 18

A: By combining radiolabeled white blood cell imaging and bone marrow imaging.

Question 19

What conditions, besides metastases, are bone scans useful for?

Answer 19

Metabolic bone diseases (e.g., Paget’s disease).
Avascular necrosis of the bone.
Soft tissue calcification (e.g., heterotrophic calcification).
Arthropathies (inflammatory/degenerativ

Question 20

What is the greatest utility of nuclear medicine in musculoskeletal imaging?

Answer 20

A: Early detection of bone metastases and whole-body imaging with low radiation doses.

Question 21

: Name a PET radiotracer used for infection and bone metastases imaging.

Answer 21

A: 18F FDG.

Question 22

Which type of bone metastases is predominantly caused by prostate cancer?

Answer 22

A: Osteoblastic.

Question 23

Q: True or False: Bone scans can detect metabolic bone diseases.

Answer 23

A: True.

Question 24

Q: True or False: A 3-phase bone scan is useful for diagnosing osteomyelitis in violated bone.

Answer 24

A: False.

It requires 99mTc-labeled white cell imaging.