Radiographic features of Osteoarthritis and Rheumatoid Arthritis Flashcards
describe the usual distribution of primary OA
asymmetrical within or between joints, and usually weightbearing or active joints
describe the affect of OA on the joint space
asymmetric cartilage wear leads to asymmetric joint space reduction
describe the process that leads to sclerosis of subchondral bone in OA
increase in subchondral bone vascularity and cellularity drives new bone formation
describe how cysts are formed in OA
synovial fluid dissects into bone
describe how osteophytes are formed in OA
periosteal stimulation leads to marginal osteophyte stimulation
what pathology can arise in weakened bone in OA
can cave in resulting in gross joint deformity
describe the distribution seen on RA
joint involvement usually symmetrical, only affects synovial joints
what are the common sites of RA involvement
MCP, MTP, PIP in hands, wrists, hips, knees, shoulders
describe how RA causes soft tissue swelling
synovial proliferation and reactive joint effusion
describe how periarticular osteoporosis is caused in RA
hyperaemia causes bone demineralisation which leads to osteoporosis
describe how joints are eroded in RA
inflamed thickened synovium(pannus) destroys bone
what are the features that contribute to deformity in RA
erosion shortens bone so capsule + ligaments become lax, inflammation softens ligaments, tendon failure
what are the radiological features seen in RA
deformity, erosion, periarticular osteoporosis, soft tissue swelling
what are the radiological features seen in OA
osteophytes, sclerosis, joint deformity, cysts, joint space reduction
what is the role of imaging in arthritis
to detect disease features to make a diagnosis and to monitor disease activity + treatment response
