Imaging Arthritis Flashcards
What is the role of imaging in arthritis
To detect features of disease in order to make a diagnosis and monitor disease activity and response to treatment
What joints are usually affected in osteoarthritis
Weight bearing or active joints:
spine, hip, knee, thumb base, DIP
When are other joints affected by OA
Overuse, previous injury or previous arthritis
Describe the location of the joints involved in OA
Usually asymmetrical
What are the 4 features of OA on an XRay
Cysts
Oestophyte formation
Synovitis
Loss of joint space
What is the appearance of osteophytes in OA
common bony white projections
Describe the distribution of RA
usually symmetrical
What joints can RA affect
MCP, MTP
PIP (not DIP)
Wrists, hips, knees, shoulders
Atlantoaxial joint (C1,2)
What happens to the synovium in RA
The synovium becomes vascular, inflamed and thickened up
Soft tissues are thickened
This washes mineral out of adjacent bone and reduced the bone density
What destroys bone and where
Inflammatory pannus - initially at the joint margins
What does hyperaemia cause
Bone demineralisation resulting in periarticular osteoporosis
In RA, what allows joint subluxation and deformity
Capsular and ligamentous softening
What do erosions causes
Shortening of the bones producing lax ligaments and joint capsule
What is ankylosis
When exposed eroded bone ends fuse
What are of the body do we image to diagnose seronegative arthritis
Sacroiliac joint and spine
What can be seen in seronegative arthritis
Intervertebral discs become ossified
Ill-defined periarticular bone formation
What joints are involved in psoriatic arthritis
Small joints of hands and feet
DIP joints, IP joint great toe
What joints are involved in ankylosing spondylitis
Scattered lower limb large joints
What joints are involved in Reiter’s syndrome
Scattered lower limb large joints
Lower limb entheses
What are entheses
The enthesis (plural: entheses) is the connective tissue between tendon or ligament and bone.
What can show increased vascularity around joints and what does that accompany?
Isotope bone scan
Accompanies synovitis
What can show the thickening of the synovium and increased blood flow within it
Colour Doppler US
What does an MR show around the SI joints
Periarticular bone marrow oedema
What does periarticular bone marrow oedema often precede
Joint erosion/ damage and provides early evidence of inflammatory joint disease
