MSK Flashcards
cardinal signs of inflammation
rubor = redness callor = hot dolor = pain tumour = swelling
what deformities do you see in RA
boutonniere
swan neck
ulnar deviation
which cells can act as APCs
macrophages
dendritic cells
b cells
give some examples of extra-articular symptoms/involvement in RA
eyes - scleritis and sicca (esp secondary to sjogrens)
skin - nodules and vasculitis
soft tissue - bursitis, tenosynovitis and muscle wasting
kidneys - amyloidosis
lungs - pleural effusions
CVS - pericarditis, pericardial rub
neuro - polyneuropathy
haematological - anaemia and splenomegaly
difference in morning stiffness in OA and RA
OA 60 mins
difference in joint involvement in OA and RA
OA - weight bearing joints, CMCJ and DIPJ
RA - NEVER DIPJ
–> symmetrical involvement of small joints of hands and feet, common in wrists, MCP and PIPs
examples of TNF-a inhibitors used in RA and explain mechanism of action
etanercept, infiliximab, adalimumab
- -> bind to TNF and prevent its interaction with receptors (remove it from inflam sites and prevent it reaching its receptors)
- -> prevents its effects of mediating/stimulating release of other cytokines
what is tocilizumab and how does it work
= DMARD - IL-6 inhibitor
- -> binds to IL receptor therefore prevents IL-6 from binding and inhibiting cell communication
- -> inhibits production of more T and B cells and therefore reduces inflam at joints
what is anakinra
IL-1 inhibitor
what is rituximab and how does it work
= B cell inhibitor
targets CD20 and prevents the release of cytokines and inflam mediators
also prevents B cells acting as APCs
what is abatacept and what is its mechanism of action
= t cell inhibitor
decreases t cell activation and prolif
decreases release of pro-inflam cytokines
upstream modulation (preventing downstream changes)
decreases autoAb production
regulates function of CD4+ cells
what triad of features do you see in Felty’s syndrome
seropositive RA
splenomegaly
neutropenia
why are women at higher risk of osteoporosis post-menopause
because bone turnover occurs more rapidly in the absence of oestrogen –> more bone resorbed than reformed –> bone loss
how does cortisol lead to osteoporosis
it increases bone resorption and induces osteoblast apoptosis (–> decreased bone formation)
composition of bone
70% mineral cortex - mostly HYDROXYAPATITE = ca and phosphate
30% organic cortex - mostly type 1 collagen fibres
actions of PTH leading to increased serum Ca
increased osteoclastic resorption of bone
increased interstitial absorption of Ca
increased synthesis of 1,25 dihydroxy-vit D
increased renal tubular reabsorption
4 secondary causes of sjogrens
SLE
systemic sclerosis
primary biliary cirrhosis
RA
Main clinical features of sjogrens
SICCA COMPLEX = dry eyes dry mouth enlarged parotid/salivary glands (plus systemic features)
systemic features of sjogrens
fatigue vasculitis arthritis raynauds lymphadenopathy dysphagia/abnormal oesophagus
what auto-Abs might you see in sjogrens
Anti-Ro, anti-La, RF, and ANA
Ix for sjogrens
schirmer’s test
gland bx –> rose bengal stainign –> keratinitis
Immunology - Anti-Ro, anti-La, RF, and ANA
lab abnormalities - raised Ig levels, raised immune complexes etc
define polymyositis
= progressive symmetrical proximal weakness and AI muscle inflam, ± myalgia ± arthralgia
what is antiphospholipid syndrome characterised by
thrombosis
&/or recurrent miscarriages
& persistent +ve blood tests for antiphospholipid antibodies
How do you treat APS and how does this differ in pregnancy
in pt with history of thrombosis give long term warfarin
in pregnant give aspirin and heparin –> decrease risk of miscarriage, but pre-eclampsia and poor foetal growth still common
What are the common features in the seronegative spondyloarthropathies
Asymmetrical large joint mono/oligoarthritis
Enthesitis
Dactylitis
Extra-articular features e.g. anterior uveitis
Strong association with HLA B27
two types of crystals that account for most of the crystal arthritis
sodium urate
calcium pyrophosphate
where are tophi in tophaceous gout most likely to form
ear, fingers and achilles tendon
what are some associated disorders of fibromyalgia
depression chronic headache IBS chronic fatigue syndrome myofascial pain syndrome
What is an important complication in juvenile idiopathic arthritis
chronic uveitis due to inflam can –> to loss of sight
If JIA dx = REFER TO OPTHALMOLOGIST
define a fracture
soft tissue injury in which there is also a break in continuity of surface/sub-structure of a bone
