Imaging of the bones

Question 1

Most common one………………………………………….

Answer 1

Conventional X-rays, always in two perpendicular planes.

Question 2

What is a stress film

Answer 2

An X ray taken on a joint when there is some pressure or load being borne by the bones, in order to see the relationship of the joint when it is at rest and when the bones have to carry weight.

Question 3

What are the two main imaging methods

Answer 3

X-ray

CT scans

Question 4

What bones is a CT scan better suited for than conventional X-Rays?

Answer 4

The Face and Skull

It is also very good for the Pelvis,
shoulder, feet, spine, in complex injuries.

Question 5

What imaging is used to guide bone biopsies?

Answer 5

CT guided bone biopsy.

Question 6

What method is used to visualize Joints

Answer 6

MRI.

Can view the cartilage, ligaments, tendons, meniscus

Question 7

What are the benefits of MRI

Answer 7

Can visualize associated soft tissue and can also sometimes visualize micro fractures of early osteoporosis better than X-ray or CT.

Question 8

What is used to locate bone metastases?

Answer 8

Tc-MDP, Technetium bisphosphonate. Absorded by bone as part of normal metabolism.

Areas of increased bone turnover have increased Tc-MDP uptake.

Bone scan is performed pior to injection and 2-3 hours after TC-MDP injection, during the late metabolic phase, when the majority of unbound tracers have been excreted from the blood by the kidney

Or in 3 phases,

1) one minute long scan at time of injection to view the perfusion.
2) Early blood content phase 5-10 minutes after injection.
3) late phase, 2-3 hours after.

Question 9

How do benign bone tumors differ from malignant ones on scintigraphy.

Answer 9

Malignant lesions show increased uptake in the early phase after tracer injection

Benign lesions do not show increased uptake until the later phase, and have more moderate signal even in the late phase than malignant ones.

Question 10

What lesions have increased signal on bone scintigraphy?

What lesions have decreased signal.

Answer 10

Osteomyelitis - in all 3 phases

Malignant lesions - all 3 phases

Benign lesions - in late phases

Occult fractures/pathologic fractures -

Aseptic necrosis will have noticeable signal Decrease compared to surrounding bone.