Osteoarthritis Flashcards
What is osteoarthritis?
a disease of synovial joints in which the articular cartilage becomes split, fissured and softened and gradually resorbs, sometimes down to underlying bone
subchondral bone becomes thickened and hard and there is formation of osteophytes
What are the secondary causes of osteoarthritis?
fractures (especially intra-articular injuries) joint inflammation inflammatory joint disease congenital abnormalities joint instability cartilage damage obesity
Which joints are most commonly affected?
weight bearing joints
hip and knee
What is the prevalence of hip osteoarthritis? (in learning objectives)
12% of >65 year olds
What is the prevalence of knee osteoarthritis? (in LOs)
35% of adults >75 years
What are the main presenting features of osteoarthritis?
pain
stiffness
swelling
deformity
Describe the pain in osteoarthritis?
slowly increasing in severity as the joint stiffens
morning pain may indicate inflammatory component
pain is usually exacerbated by exercise but joint often feels stiff after rest
What is a good way to assess severity of pain?
Ask - Does it disturb sleep?
How do patients describe the stiffness in osteoarthritis?
not usually a major cause of complaint - may make putting on socks difficult
Why is there swelling seen in osteoarthritis?
due to over-production or under-absorption of synovial fluid
bony swelling may result from osteophyte formation
What causes deformity in osteoarthritis?
severe destruction of the bone esp at the knee and ankle
deformity also results from soft tissue changes
can affect gait, function, and nearby joints
What is seen on inspection in osteoarthritis?
fixed deformities
swelling due to moderate synovial thickening and bony enlargement of the joint due to osteophytes and occasional effusions during acute episodes
What is seen on palpation in osteoarthritis?
tenderness around the joint
swelling
What is seen on movement in osteoarthritis?
restriction in movements
muscle spasm and pain when pushing beyond the limit
crepitus on movement
abnormalities of the goat
What are the risk factors for osteoarthritis?
age obesity genetics gender (females) hypermobility trauma congenital joint dysplasia joint incongruity leads to earlier OA occupation
What are the causes of joint incongruity that leads to earlier onset of OA in the effected joint?
congenital dislocation of the hip
slipped femoral head epiphyses
perthes disease
What are the occupations that increase the risk of OA?
miners (hip, knee and shoulder)
cotton workers (hand)
farmers (hip)
What are the causes of secondary causes of OA?
pre-existing joint damage (RA, gout, seronegative spondyloarthropathy, septic arthritis, pages disease, avascular necrosis)
metabolic disease (acromegaly, chonedrocalcinosis, hereditary hameochromatosis)
systemic disease (haemophilia due to hamearthrosis, haemoglobinopathies, neuropathies)
What is the difference between primary and secondary OA?
primary OA - no identifiable causes
secondary OA - identifiable cause
What are the different types of primary OA?
localised OA - nodal and erosive
erosive OA
What is nodal OA?
joints of the hand are affected one at a time over several years
DIP joints are affected more than PIP joints
How does nodal OA present and progress?
onset may be painful with swelling and impairment of hand function, often around female menopause inflammatory phases settles leaving painless bony swellings, stiffness and deformity function is not usually affected
Where are Heberden’s nodes?
nodes around DIP
What are Bouchard’s nodes?
nodes around the PIP
What is erosive OA?
also called inflammatory arthritis
rare
DIPs and PIPs are inflammed and equally affected
may develop into RA and may not be true subset of OA
What is primary generalised OA?
associated with immune complex formation and may have an autoimmune cause
female predominance
strong familial tendency
What joints are affected in primary generalised OA?
knee, first metacarpophalangeal joint, hip and intervertebral joints are affected
onset is often sudden and severe
What is an example of secondary OA?
crystal associated OA
What is crystal associated OA?
chonedrocalcinosis
calcium pyrophosphate deposition in the cartilage
increases in frequency with age
usually asymptomatic
knees and wrist are commonly affected, then shoulders, elbows, ankles and hips
What is seen on X-ray in crystal associated OA?
patchy linear calcification on x-ray with osteophytes and cyst formation
How does the rare, more severe form of crystal associated OA present?
rapidly destructive arthritis
found in elderly women
deposition of calcium apatite in a bloody joint effusion
affects the shoulders, hips and knees
poor outlook that requires early surgical replacement
