Osteoarthritis and Crystal Arthropathies Flashcards
how common is osteoarthritis (OA)?
1/3 of people over 45
1/2 people over 70
8 million people in UK
what does OA do?
destruction of articular cartilage
how does OA appear on X ray?
decrease in joint space
usually a space is sees as cartilage doesn’t appear, when cartilage lost, bone are tight together
what causes OA?
wear and tear in the joints
partly a consequence of ageing but many other risk factors
OA risk factors?
age female obesity previous injury (occupation, sports) muscle weakness proprioceptive deficits genetic elements acromegaly joint inflammation crystal deposition
4 components of cartilage?
water
chondrocytes
proteoglycan
collagen filaments
what can cause a solid, bony swelling in OA?
formation of osteophytes
what can cause secondary OA?
injury
calcium crystal deposition (pseudogout)
RA
etc
what jobs give increased OA risk/earlier presentation?
manual jobs (e.g farmers)
what joints does OA affect?
weight bearing joints
most commonly used joints (neck, thumb base)
does OA affect MCP joint?
generally no
OA vs RA sites?
RA can only affect C1 and C2
OA can affect whole spine
describe the clinical presentation of OA?
pain worse on activity and relieved by rest - can progress to become painful with little/no activity
morning stiffness lasting less than 30 mins
slow progression (years)
OA examination features?
crepitus (friction of bones)
joint swellings (osteophytes)
sometimes tenderness and effusion
clinical hand features of OA?
affects DIPs and CMC joint
not MCP
bony enlargements
squaring of hand
what are heberdens nodes?
bony enlargements at DIPs
what are bouchard’s nodes?
bony enlargements at PIPs
clinical knee features of OA?
osteophytes effusions crepitus restricted movement Genu varus/vlgus deformities bakers cyst (in popliteal fossa)
clinical hip features of OA?
pain may be felt in groin or radiating to knee
restricted hip movement
clinical spine features of OA?
cervical = pain and restriction of movement lumbar = pain on walking or standing
what causes spinal symptoms in OA?
destruction of IV discs
what is a possible complication of OA in the spine?
osteophytes can cause spinal stenosis if they encroach on spinal canal or pinch nerve root
how is OA diagnosed?
radiological - loss of joint space, subchondral sclerosis and cysts, osteophytes
clinical - mechanical pain, sites of pain, history etc
how is OA graded?
Kellgren-Lawrence
0 = no radiological findings
1 = minute osteophytes
2 = definite osteophytes with unimpaired joint space
3 = definite osteophytes with moderate joint space narrowing
4 = definite osteophytes with sever joint space narrowing and subchondral sclerosis
hands vs knees vs hips progression?
hands - pain often improves over 2 years
knees - 1/3 improves, 1/3 stays same, 1/3 gets worse
hip - 10% symptoms improve
non-pharmacological management of OA?
explanation - keep moving
physiotherapy
common sense - weight loss etc
pharmacological management of OA?
analgesia
NSAIDs - mainly gels
Pain modulators - anti-convulsants, tricyclics (amitriptyline)
Intra-articular - steroids (occasionally hyaluronic acid helps)
definitive OA treatment?
surgical
joint replacement
washout and soft tissue trimming can also help
what is gout?
inflammation in the joint triggered by uric acid crystals
normal uric acid level?
0.42 mmol/l
above 0.42 it becomes insoluble and precipitates out (hyperuricaemia)
common sites of gout?
big toe
fingers
what can cause increased uric acid production?
enzyme defects increased cell turnover disorders (leukaemia, lymphoma, psoriasis etc) haemolytic disorders alcohol link high purine diet (red meat, seafood)
causes of reduced urate excretion?
chronic renal impairment volume depletion (heart failure) hypothyroidism diuretics cytotoxics (cyclosporin)
who is gout more common in?
men
doesn’t really occur in women before the menopause
is gout mono, orli or poly arthropathic?
usually mono (one joint)
how does gout arise and resolve?
arises overnight often
settles in 10 days without treatment or 3 days with treatment
what does gout look like?
very sudden red swelling over a joint
how does uric acid change during an acute attack?
can be normal
chronic tophaceous gout?
chronic joint inflammation often diuretic associated high serum uric acid tophi involved may get acute attacks
how is gout investigated?
blood test - raised inflammatory markers - serum uric acid raised (or normal if acute) synovial fluid microscopy renal impairment X ray
how is acute gout treated?
NSAIDs
colchicine
steroids
how is chronic gout treated via prophylaxis?
allopurinol (must be with NSAIDs etc)
Febuxostat
when is gout prophylaxis started?
2-4 weeks after acute attack
what is deposited in pseudogout?
calcium pyrophosphate
what happens in pseudogout?
fibrocartilage in knees, ankles and wrists affected
chondrocalcinosis
what are the 2 types of calcium crystal deposition?
calcium pyrophosphate (CPP) crystals (pseudogout) calcium hydroxyapatite crystals
what age group is pseudogout common in?
elderly
what do CPP crystals look like?
envelope shaped
how is CPP treated?
NSAIDs
cochicine
steroids
rehydration
what is hydroxyapatite?
“Milwaukee shoulder”
deposition of hydroxyapatite crystals
usually in 50-60 y/o females
what happens in hydroxyapatite?
release of collagenases, serine proteases and IL1
acute and rapid deterioration
how is hydroxyapatite treated?
NSAIDs
intra-articular steroid injection
physiotherapy
partial or total arhtroplasty
what is soft tissue rheumatism?
General term to describe pain caused by inflammation to muscle, tendon, ligament, nerve etc near a joint rather than the joint itself
how does pain appear in soft tissue rheumatism?
usually localised to a specific site
what is a more generalised soft tissue pain suggestive of?
fibromyalgia
what is the most common area for soft tissue pain?
shoulder
what can cause soft tissue pain in the shoulder?
adhesive capsulitis rotator cuff tendinosis calcific tendonitis impingement partial rotator cuff tears full rotator cuff tears
where else does soft tissue pain commonly occur?
elbow
wrist
pelvis
foot
name some causes for soft tissue pain
carpal tunnel
bursitis
plantar fascitis
how is soft tissue rheumatism treated?
pain control rest ice compress PT steroid injections surgery
how is soft tissue rheumatism investigated?
usually not needed
x ray can show calcific tendonitis
how does joint hypermobility syndrome present?
arthralgia premature osteoarthritis normal investigations can be general or local more common in females and usually presents in childhood or 3rd decade
what can cause joint hypermobility?
genetic syndromes
- marfans
- ehlers danlos syndrome
how is joint hypermobility treated?
physiotherapy
explanation to the patient
what is modified beighton score?
classification of hypermobility
if >4 of the 9 features = hypermobility
what are the features of the modified beighton score?
- > 10 degree hyperextension of the elbow
- passively touch the forearm with the thumb
- passive extension of the fingers or a 90 degree+ extension of the fifth finger
- hyperextension of the knees >10 degrees
- touching the floor with the palms of the hands without bending the knees
