Radiology of Arthritis and Bone Pathologies Flashcards
What is meant by a ‘distracted’ fracture?
Bone pieces are pulled apart in the fracture
What is meant by a ‘comminuted’ fracture?
Bone is broken up into lots of small pieces
What is meant by a ‘compound’ fracture?
Open to the skin, more likely to be infection
What is meant by a ‘overriding’ fracture?
Dense, sclerotic lesion due to overriding bits of bone
Extra-articular fractures are at higher risk for development of arthritis than intra-articular fractures. t/f?
False - the opposite is true
Why do intracapsular fractures of the femoral head require surgical intervention?
These fractures are at high risk of avascular necrosis.
What sign on x-ray is specific for Paget’s disease?
Blade of grass sign
What type of joint changes are seen in degenerative arthritis?
Increased bone production - osteophytes
What type of joint changes are seen in inflammatory arthritis?
Periarticular erosions
What type of joint changes are seen in depositional arthritis?
Periarticular soft tissue masses
Active erosions are likely to appear well-defined on x-ray. T/F?
False - active erosions are ill-defined, old erosions are well-defined
What is primary degenerative arthritis?
Intrinsic degeneration of the articular cartilage caused by excessive wear and tear
What joints are commonly affected by primary degenerative arthritis?
Hips
Knees
What signs of primary degenerative arthritis are seen on x-ray?
Narrowed joint spaces
Osteophytes
Subchondral sclerosis/cysts
What is secondary degenerative arthritis?
Arthritis caused by another process which destroys the articular cartilage
What are the common causes of secondary degenerative arthritis?
Trauma Infection Avascular necrosis CPPD RA Haemophilia
What are the uncommon causes of secondary degenerative arthritis?
Haemachromatosis
Acromegaly
Ochronosis
Wilson’s disease
Any type of arthritis can end up as degenerative arthritis. T/F?
True
What is CPPD caused by?
Hyperparathyroidism
Haemachromatosis
What changes are seen in CPPD?
Similar to OA but symmetrical and unusual distribution
Chonedrocalcinosis - calcification of the articular cartilage
Triangular fibrocartilage of the wrist, knee, hip, shoulder an symphysis pubis
What is the acute presentation of CPPD?
Sudden onset of pain or fever
Joint appears tender, swollen and red
May mimic septic arthritis
What are the possible causes of inflammatory arthritis?
Infection
RA
Seronegative arthropathies
Other connective tissue diseases
What are the possible causes of seronegative arthropathies?
Psoriatic arthritis
Reactive arthritis
Ankylosing spondylitis
Inflammatory bowel disease
What systemic connective tissue diseases can cause inflammatory arthritis?
Scleroderma
SLE
In what age group is infectious arthritis most common?
Adults
When does infectious arthritis commonly occur?
After local injury or surgery
Which joints are typically affected in infectious arthritis?
Fingers due to bites
Feet due to diabetes
Hip due to hip replacement
Usually only one joint affected
Which organisms commonly cause infectious arthritis?
Staph
Step
TB
What are the signs (clinical and on x-ray) of infectious arthritis?
Soft tissue swelling Destruction of cartilage and bone Rapid loss of joint soace Possible periosteal reaction Osteoporosis Subluxation OA Fusion
What signs will be seen on imaging in discitis?
End-plate erosion Disc space narrowing Bone destruction Paravertebral masses Sclerosis Anklyosis
What are the signs (clinical and on x-ray) of RA?
Hyperaemia Soft tissue swelling Synovitis Effusion Bone marrow oedema Erosions Cysts Joint space narrowing Secondary degenerative changes Loose bodies
Which gene is particularly associated with serous-negative inflammatory arthropathies?
HLA-B27
What classical deformity can be seen on x-ray in patients with psoriatic arthritis?
Pencil and cup deformity
What is retire syndrome?
Triad of urethritis, arthritis and conjunctivitis
Describe the epidemiology of renter’s syndrome
Male>female
White>black
20-40 years
How long after infection does renter’s syndrome occur?
1-3 weeks
What joints are commonly affected by renter’s syndrome?
Sacro-iliac
Lower limb joints
What are the presenting complaints of a patient with ankylosing spondylitis?
Low back pain and stiffness
Which joints are usually affected by ankylosing spondylitis?
Sacro-iliac
In which cause of inflammatory arthritis would you see a ‘bamboo spine’ on imaging in late disease?
Ankylosing spondyltiis
What condition is characterised by urate crystal deposition?
Gout
What is the epidemiology of gout?
Common in elderly men
Often hereditary
What joints are commonly affected by gout?
Foot, knee, hand, elbow
