Radiology - Monoarticular joint pain

Question 1

Distribution in OA

Answer 1

Distal AND symmetrical

Interphalangeal and base of thumb

Question 2

Distribution in PsA

Answer 2

Distal AND Asymmetrical

Interphalangeal

Question 3

Distribution in RhA

Answer 3

Proximal AND symmetrical

MCP, PIP and carpal joint

Question 4

X-ray features of infl arthritis

Answer 4

Swelling
Joint space loss
Osteoporois
Erosions

Question 5

X-ray features of degenerative arthritis

Answer 5

Joint space loss
Sclerosis
Cysts
Osteophytes

Question 6

Erosions

Answer 6

A hole in bone, adjacent to a joint, w/ NO roof

Question 7

Cysts

Answer 7

A hole in bone, adjacent to a joint, w/ a roof

Question 8

Subchondral cysts

Answer 8

Focal areas of loosening w/ a roof
Occur in area adjacent to joints and more central
Have thin sclerotic rim

Question 9

Geode subchondral cysts

Answer 9

Large hole or amalgamation of several small cysts

Question 10

Erosion or cysts

Answer 10

Oblique view - displays roof

‘Setting sun’ - erosion

Question 11

Where are osteophytes usually found

Answer 11

Margin of joints

Question 12

Enthesal proliferations

Answer 12

Usually further from the joint

Fluffier, less defined than osteophytes

Question 13

Why is there swelling in infl arthritis

Answer 13

Joint effusions

Synovial hypertrophy

Question 14

Why is there juxta-articular osteoporosis in infl arthritis

Answer 14

increase in blood supply to joint —> increases bone turn over —> reduces bone mineral density next to the joint

Question 15

Marginal erosions in infl arthritis

Answer 15

Synovium releases proteolytic enzymes erode nearby cartilage and bone

Question 16

Joint space loss in degenerative arthritis

Answer 16

Irregular due to destruction go the articular cartilage

Question 17

Sclerosis in degenerative arthritis

Answer 17

Osteoblastic response to extra loading on adjacent trabeculae due to loss of cartilage

Question 18

Subchondral cysts in degenerative arthritis

Answer 18

Collection of synovial fluid forced through microscopic fissures in the hyaline cartilage into cavities. Collected under pressure is supposed to slow remodelling of subchondral bone

Question 19

Margins in infl vs degenerative arthritis

Answer 19

Normal vs osteophytes

Question 20

Mineralisation in infl vs degenerative arthritis

Answer 20

Juxta-articular osteoporosis vs subchondral sclerosis

Question 21

Codman triangle

Answer 21

Triangular area of new subperiosteal bone that is created when a lesion, often a tumour, raises the periosteum away from the bone

Question 22

Sunburst appearance

Answer 22

Reaction of periosteum
Occurs when lesion grown too fast
Usually seen in osteosarcoma and Ewing’s sarcoma

Question 23

What appears bright on a MRI scan

Answer 23

Fat

Water