Radiology - Monoarticular joint pain Flashcards
Distribution in OA
Distal AND symmetrical
Interphalangeal and base of thumb
Distribution in PsA
Distal AND Asymmetrical
Interphalangeal
Distribution in RhA
Proximal AND symmetrical
MCP, PIP and carpal joint
X-ray features of infl arthritis
Swelling
Joint space loss
Osteoporois
Erosions
X-ray features of degenerative arthritis
Joint space loss
Sclerosis
Cysts
Osteophytes
Erosions
A hole in bone, adjacent to a joint, w/ NO roof
Cysts
A hole in bone, adjacent to a joint, w/ a roof
Subchondral cysts
Focal areas of loosening w/ a roof
Occur in area adjacent to joints and more central
Have thin sclerotic rim
Geode subchondral cysts
Large hole or amalgamation of several small cysts
Erosion or cysts
Oblique view - displays roof
‘Setting sun’ - erosion
Where are osteophytes usually found
Margin of joints
Enthesal proliferations
Usually further from the joint
Fluffier, less defined than osteophytes
Why is there swelling in infl arthritis
Joint effusions
Synovial hypertrophy
Why is there juxta-articular osteoporosis in infl arthritis
increase in blood supply to joint —> increases bone turn over —> reduces bone mineral density next to the joint
Marginal erosions in infl arthritis
Synovium releases proteolytic enzymes erode nearby cartilage and bone
Joint space loss in degenerative arthritis
Irregular due to destruction go the articular cartilage
Sclerosis in degenerative arthritis
Osteoblastic response to extra loading on adjacent trabeculae due to loss of cartilage
Subchondral cysts in degenerative arthritis
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
Margins in infl vs degenerative arthritis
Normal vs osteophytes
Mineralisation in infl vs degenerative arthritis
Juxta-articular osteoporosis vs subchondral sclerosis
Codman triangle
Triangular area of new subperiosteal bone that is created when a lesion, often a tumour, raises the periosteum away from the bone
Sunburst appearance
Reaction of periosteum
Occurs when lesion grown too fast
Usually seen in osteosarcoma and Ewing’s sarcoma
What appears bright on a MRI scan
Fat
Water
