MSK/Rheumatology 6/7/20 Flashcards
contraindicated drugs for patients on methotrexate
- trimethoprim
- cotrimoxazole (septrin)
- high dose aspirin
cause bone marrow toxicity
inflammatory vs degenerative
- stiffness
> over 30-60 mins/better with exercise/morning = inflammatory
> under 30 mins/worse with exercise = degenerative - joint distribution
> hands and feet = inflammatory
> knees, fingers, thumb base = degenerative
MSK history red flags
BONE PAIN
- at rest/at night - possibly tumour/infection/fracture
NEURALGIC
- pain/paraesthesia in dermatomal distribution - possibly root or periph nerve compression
INFECTIVE
- warm, usually monoarthralgia
complications of rheumatoid arthritis
- interstitial lung disease (pul fibrosis)
- pleural effusion
- pericardial effusion leading to cardiomegaly
- nephrotic syndrome, check kidney function and oedema
- vasculitis, small vessels of nose/digits more commonly
blood tests to monitor methotrexate
3 monthly when stable on drug, fortnightly before stable
- FBC (pancytopenia risk)
- U+Es (renally excreted)
- LFTs (methotrexate binds to albumin)
ecg changes in pericarditis
- ‘saddle-shaped’ ST elevation
- PR depression: most specific ECG marker for pericarditis
methotrexate in those trying for baby
remember methotrexate is teratogenic (men and women come off methotrexate for 3 months before trying for baby)
safe alternatives to methotrexate in pregnancy/breastfeeding
- sulfasalazine
- hydroxychloroquine
co-prescribe methotrexate with…?
weekly folic acid (>24hrs after methotrexate dose)
biologic DMARDs key points
- more potent immunosuppressants than regular DMARDs, at risk of atypical and typical infections
- stop bDMARDs for duration of Abx and 2 weeks after
- for elective surgery stop bDMARDs for half life + 1 wk
radiological changes of rheumatoid arthritis
LESS
Loss of joint space
Erosions
Soft tissue swelling
Soft bones (oteopenia)
examples of anti-TNF biologic DMARDs
- infliximab
- etanercept
examples of lymphocyte suppressing biologic DMARDs
T cells = abatacept
B cells = rituximab
example of anti-IL6 biologic DMARDs
Tocilizumab
fractures that have highest risk of compartment syndrome as a complication
- supracondylar fracture (humerus just above elbow)
- tibial shaft fracture
diagnosis of compartment syndrome
measurement of intracompartmental pressure:
- pressure >20mmHg = abnormal
- pressure >40mmHg is diagnostic
compartment syndrome does not typically show pathology on x-ray
features of compartment syndrome
6 Ps but not always all 6
- severe Pain, especially on passive movement and not relieved even by morphine
- Parasthesiae
- Pallor/Poikilothermia may be present
- Pulselessness (pulse may still be felt as the necrosis occurs as a result of microvascular compromise)
- Paralysis of the muscle group may occur
complications of compartment syndrome
- necrosis (can lead to muscle contractures eg. Volkmann’s contracture)
- rhabdomyolysis/AKI
management of compartment syndrome
- surgical (fasciotomy) to relieve pressure
- give fluids to prevent AKI if rhabdomyolysis occurs
- if due to an external factor (eg. misplaced cast) removal may provide spontaneous recovery
management must be prompt as muscle group death may occur within 4-6hrs
causes of compartment syndrome
- trauma (fracture, crush, gunshot)
- external (tight cast, burns)
- internal (fluid overload, post-ischaemic swelling, bleeding disorders)
muscles and function of anterior compartment
muscles: - tibialis anterior - extensor hallucis longus - extensor digitorum longus - peroneus tertius function: - dorsiflexion of ankle/foot
muscles and function of lateral compartment
muscles: - peroneus longus - peroneus brevis function: - plantarflexion of foot - eversion of foot
muscles and function of deep posterior compartment
muscles: - tibialis posterior - flexor digitorum longus - flexor hallucis longus function: - plantarflexion of foot - inversion of foot
muscles and function of superficial posterior compartment
muscles: - gastrocnemius - soleus - plantaris function: - plantarflexion of foot
FRAX criteria
- age
- sex
- height, weight, BMI (frailty)
- previous fracture
- parent fractured hip
- glucocorticoids
- rheumatoid arthritis
- secondary osteoporosis (type 1 diabetes, hyperthyroid/parathyroidism, chronic liver disease, premature menopause, IBD/coeliac , etc.)
- diet/alcohol/smoking
- BMD scan result
osteoporosis/penia T score
osteopenia = -1 to -2.5 osteoporosis = -2.5 or lower
confirm osteoporosis wit DEXA scan
side effects of bisphosphonates
- oesophagitis (orally), dosing instructions reduce risk
- IV bisphosphonates may cause flu-like symptoms
- AF risk
RARE
> osteonecrosis of jaw
> atypical femoral fractures
bisphosphonate dosing instructions PO
- take on empty stomach in morning
- swallow with big glass of water
- no food/drink/meds for at least 30 mins
- stay sat/stood up after taking to reduce oesophagitis/reflux risk
denosumab
- monoclonal antibody to RANK ligand
- prevents osteoclast differentiation and reduces activity
- 6 monthly subcut injection
- suited to older/frailer patients
teriparatide
- PTH analogue
- stimulates osteoblast activity
- daily subcut injection for 2 yrs
- expensive so reserved for those with severe osteoporosis unresponsive to bisphosphonates
Paget’s disease of bone pathophysiology
genetic and geographical factors
- bone remodelling disorder
- overactive osteoclasts
- compensatory increased osteoblast activity
- disorganised mosaic of woven (weak) and lamellar (strong) bone
Paget’s disease of bone features
triad of: - pain - deformity - fracture RARELY: - deafness - myelopathy (-> spinal cord compression)
radiological signs of Paget’s disease of bone
- expansion of bone
- cortical thickening
- abnormal texture
biochemistry of Paget’s
- high AlkPhos
- Ca/Phos usually normal
management of Paget’s
- bisphosphonate eg. alendronate (counter overactive osteoclasts)
- surgery may be required for complications
symptoms of hypercalcaemia
- polydipsia
- polyuria
- constipation
- nausea
later:
- confusion/coma
- renal stones
- short QT interval
skin manifestations of systemic lupus erythematosus (SLE)
- photosensitive ‘butterfly’ rash
- discoid lupus
- alopecia
- livedo reticularis: net-like rash
- Raynaud’s phenomenon
cardiovascular manifestations of systemic lupus erythematosus (SLE)
- pericarditis
- myocarditis
- cardiomyopathy
renal manifestations of systemic lupus erythematosus (SLE)
- proteinuria
- glomerulonephritis (diffuse proliferative glomerulonephritis is the most common type)
respiratory manifestations of systemic lupus erythematosus (SLE)
- pleurisy and pleural effusions
- fibrosing alveolitis
neuropsychiatric manifestations of systemic lupus erythematosus (SLE)
- anxiety and depression
- psychosis
- seizures
general features of SLE
- fatigue
- fever
- mouth ulcers
- lymphadenopathy
- ANA and anti-dsDNA autoantibodies
adverse effects of methotrexate
- mucositis
- myelosuppression
- pulmonary fibrosis
- liver fibrosis
treatment of methotrexate toxicity
folinic acid
adverse effects of sulfasalazine
- oligospermia
- Stevens-Johnson syndrome
- lung fibrosis
- myelosuppression
- may colour tears → stained contact lenses
sulfasalazine cautions
- G6PD deficiency
- allergy to aspirin or sulphonamides (trimethoprim)
osteoarthritis radiological signs
JOSS
- joint space narrowing
- osteophytes
- subchondral sclerosis
- subchondral cysts
features of cauda equina syndrome
- lower back or sciatica pain
- urinary incontinence/retention
- saddle paraesthesia
- decreased anal tone
management of cauda equina syndrome
Urgent MRI
acute: - surgery to decompress - Abx if abscess is cause degenerative: - surgery if possible - NSAIDs/corticosteroids
management of a fracture
ALL FRACTURES
- Immobilise the fracture (including the proximal and distal joints)
- Monitor neurovascular status
OPEN FRACTURES
- IV broad spectrum antibiotics
- Lavage and debridement within 6 hours of injury
GU complications of pelvic injury
- haematuria
- urinary retention
- urethral injury
- bladder injury
causes of anaemia of chronic disease
- malignancy
- chronic infections eg. TB
- connective tissues disease eg. rheumatoid arthritis
RFs for adhesive capsulitis (frozen shoulder)
- age 40-60
- diabetes
- cardiovascular disease
management of adhesive capsulitis (frozen shoulder)
stiffness may persist for months/years
- analgesia
- physio and exercise
- intracapsular steroid injection
upper brachial plexus injury
- Erb’s palsy
- associated C5, C6 dermatomal sensory loss
lower brachial plexus injury
- Klumpke’s palsy (claw hand due to myotomal loss)
- associated C8, T1 dermatomal sensory loss
- T1 can lead to ipsilateral Horner’s
features of shoulder impingement
- pain and stiffness
- particularly when doing overhead movements
- management is with analgesia, physio, rarely surgical decompression
osteosarcoma
most common bone malignancy
- adolescent males typically
- warm, painful swelling
- periosteal sunburst appearance
Ewing’s sarcoma
- adolescents
- warm, painful, growing mass along long bone
- systemic features (inc WCC, ESR, fever, anaemia)
- onion skin periosteal reaction
chondrosarcoma
- older patients
- pain with a mass in cartilage
- ‘fluffy popcorn calcification’ lesion
assessment for C-spine injury
ABCDE
- full immobilisation until C-Spine ‘cleared’
- detailed history and examination
- imaging as required
management of confirmed C-spine injury
ABCDE
- airway management
- secure patient with full in-line stabilisation
- maintain ‘neutral’ neck position, use a jaw thrust if required rather than chin lift
- semi-rigid collar
- secure head with blocks and tape
most common nerve lesion causing foot drop
common peroneal nerve injury
management of OA
- weight loss and aerobic exercise are effective at reducing pain and maintaining joint function
- weight-bearing exercise should be avoided as it can accelerate the progression of the disease
- physiotherapy and occupational therapy input
- walking aids may be useful
- NSAIDs particularly effective
- surgery may be required
management of osteomyelitis/septic arthritis
commonly due to staph aureus
- flucloxacillin (clindamycin if pen allergy) for 4-6 wks (12+ in chronic OM)
- surgical debridement useful in OM
- may add fusidic acid/rifampicin in severe OA for first 2 weeks
RFs for osteoporosis
SHATTERED FAMILY S – Steroid use H – Hyperthyroidism, hyperparathyroidism A – Alcohol and smoking T – Thin (BMI<22) T – Testosterone deficiency E – Early menopause R – Renal/liver failure E – Erosive/inflammatory bone disease D – Diabetes FAMILY HISTORY
autoantibodies in RA
anti-CCP (anti-cyclic citrullinated peptide)
rheumatoid factor
management of RA
- oral methotrexate and bridging steroid initially
- treat flares with oral/IA prednisolone
- second line = sulfasalazine then TNFa biologics eg. etanacept
SPINEACHE mnemonic for seronegative spondyloarthropathies
Sausage digits Psoriasis Inflammation NSAIDs effective Enthesitis Arthritis Crohn's/colitis HLA-B27 Eyes (uveitis)
management of SLE
start off with NSAIDs and hydroxychloroquine
gout crystals + management
urate crystals
negatively birefringent needles
- colchicine acutely then allopurinol
- lifestyle changes
pseudogout crystals
apatite crystals
positively birefringent rhomboids
which cancers spread to bone?
Prostate – blastic = growth-promoting Breast – mixed pattern Kidney – lytic = breakdown Thyroid – lytic Lungs – lytic
