MSK Flashcards
What is the typical age of onset of osteoarthritis?
45+
What is the pattern of joint involvement in osteoarthritis?
Asymmetrical
What are the most common joints affected in osteoarthritis?
DIPJs
Hips
Knees
Describe the joint stiffness seen in osteoarthritis.
Transient joint stiffness <30 mins
Describe the effect on movement in osteoarthritis.
Pain worsens with movement
What are the systemic symptoms of osteoarthritis?
None
What age does rheumatoid arthritis typically present?
20-40
Describe the pattern of joint involvement for rheumatoid arthritis.
Symmetrical
What are the most common joints affected in rheumatoid arthritis?
PIPJs
Wrists and feet
DIPJs rarely affected
Describe the joint stiffness seen in rheumatoid arthritis.
Early morning stiffness >30 mins
Describe the effect of movement seen in rheumatoid arthritis.
Pain eases with movement
What are the systemic symptoms of rheumatoid arthritis?
Fever and malaise
What is osteoarthritis?
Non-inflammatory degenerative arthritis
What is the pathology of osteoarthritis?
Progressive destruction and loss of articular cartilage
When can you diagnose osteoarthritis without investigations?
45+, activity related joint pain, no morning stiffness/stiffness lasting <30 mins
How do you investigate osteoarthritis?
Bloods - FBC and ESR normal
X-ray
What is the non-medical management of osteoarthritis?
Physio to improve strength/lose weight
What is the medical management of osteoarthritis?
Paracetamol/NSAIDs/intra-articular corticosteroid (hydrocortisone) injections
What should you consider prescribing with continuous oral NSAIDs?
PPIs
What is the surgical management of osteoarthritis?
Arthroscopy/arthroplasty
What is arthroscopy?
Scope inserted into joint to assess and remove loose bodies e.g. bone and cartilage fragments
What is arthroplasty?
AKA knee/hip replacement if uncontrolled pain and significantly limited function
What does an x-ray show for osteoarthritis?
LOSS
Loss of joint space
Osteophytes
Subarticular sclerosis
Subchondral cysts
What are the signs of osteoarthritis in the hands?
Heberden’s and Bouchard’s nodes
Which joint do Heberden’s nodes present in?
DIPJs
Which joint do Bouchard’s nodes present in?
PIPJs
What is rheumatoid arthritis?
Chronic systemic autoimmune disorder causing a symmmetrical polyarthritis
What type of arthritis is rheumatoid arthritis?
Inflammatory?
What makes rheumatoid arthritis an inflammatory condition?
Synovial inflammation (synovitis)
What are the genetic associations of rheumatoid arthritis?
HLA DR1/DR4
How must a patient present to diagnose rheumatoid arthritis?
5 Ss
Slowly progressive Symmetrical Swollen Stiff Systemic symptoms (+pain)
What are the extra-articular manifestations of rheumatoid arthritis?
Subcutaneous nodules
Caplan’s syndrome - swelling (inflammation) and scarring of the lungs
Felty’s syndrome - RA + splenomegaly + neutropenia
Anaemia of chronic disease
Episcleritis and scleritis
CTS
What is Caplan’s syndrome?
Pulmonary fibrosis with pulmonary nodules
What is Felty’s syndrome?
RA + splenomegaly + neutropenia
How is rheumatoid arthritis investigated?
Bloods: FBC Rheumatoid factor Anti-CCP CRP/ESR
What does FBC show for rheumatoid arthritis?
Normochromic normocytic anaemia
Describe the ESR/CRP levels in rheumatoid arthritis.
Raised (inflammation)
Describe the levels of rheumatoid factor in rheumatoid arthritis.
Raised in 80% - low specificity, high sensitivity
Describe the levels of anti-CCP in rheumatoid arthritis.
Raised in 30% - low sensitivity, high specificity
What characterises a worse prognosis of rheumatoid arthritis?
Raised anti-CCP
What does an x-ray show for rheumatoid arthritis?
LESS
Loss of joint space
Erosion
Soft tissue swelling
Soft bones
How does rheumatoid arthritis present in the hands?
Boutonnière deformity of thumb
Ulnar deviation of MCP joints
Swan-neck deformity of fingers
Z-shaped deformity of thumb
What characterises gout under polarised light microscopy?
Yellow needle shaped monosodium urate crystals, strongly negative birefrigence
What characterises pseudogout under polarised light microscopy?
Blue rod/rhomboid calcium pyrophosphate dihydrate crystals. Weak positive birefringence.
What is gout?
Inflammatory arthritis associated with chronically high blood uric acid levels
Where does the majority of gout present?
60% occurs at 1st MTPJ of big toe
What are the risk factors for gout?
Male Obesity High purine diet e.g. red meat, shellfish, beer Alcohol Diuretics Existing cardio or kidney disease FHx
What is the pathophysiology of gout?
Uric acid usually excreted out via kidneys but if there is excess uric acid and the kidneys can’t cope - converted into monosodium urate
How do the kidneys produce uric acid?
Purines > hypoxanthine > xanthine > uric acid
What enzyme is responsible for the conversion of hypoxanthine to uric acid?
Xanthine oxidase
How does acute gout present?
Sudden onset of severe pain, swelling and redness of metatarsophalangeal (MTP) joint of big toe
How many joints does acute gout usually affect?
Usually monoarticular
What differential is important to rule out in gout?
Septic arthritis - gout will have no bacteria in aspirate
Who does chronic polyarticular gout usually affect?
Patients with renal failure on long term diuretics
How does chronic tophaceous gout present?
Monosodium urate forms large, smooth, white deposits (TOPHI) in skin around the joints (particularly DIPJs/ear)
Until proven otherwise, what is the cause of any hot swollen red joint?
Septic arthritis
What is the 1st line treatment of acute attacks of gout?
High dose NSAIDs
What is the 2nd line treatment of acute attacks of gout?
Colchicine
What is the 3rd line treatment for acute attacks of gout?
Corticosteroids
How is gout prevented?
Avoid purine rich foods
Reduce alcohol consumption
Lose weight
What is allopurinol?
Xanthine oxidase inhibitor
What medication is used to TREAT gout (rather than manage)?
Allopurinol
How does allopurinol work?
Less uric acid production = less monosodium crystals
When can you start a patient on allopurinol?
Must not start until 1 month after acute attack. Once started can be taken through any following attacks
What is pseudogout?
Deposition of calcium pyrophosophate crystals on joint surface
Why does pseudogout resemble acute gout?
Shedding of crystals into joint produces acute synovitis resembling acute gout
What does an x-ray for pseudogout show?
Chondrocalcinosis = diagnostic for pseudogout
Linear calcification parallel to articular surfaces
How is pseudogout managed?
Symptoms usually resolve on their own over a few weeks
Symptomatic management includes NSAIDs/colchicine/joint aspiration/corticosteroids
What is osteoporosis?
Low bone mass = increased bone fragility and fracture risk
What are the risk factors for osteoporosis?
MY SHATTERED FAMILY
MY - personal history of fracture
Steroid use Hyperthyroidism/hyperparathyroidism Alcohol Thin (low BMI) - reduced skeletal loading Testosterone low Early menopause Renal or liver disease Erosive/inflammatory bone disease e.g. RA Dietary calcium low/malabsorption
FAMILY - parental history of fracture
What is a protective factor for osteoporosis?
Oestrogen - post-menopausal women at greater risk (less oestrogen)
What does an x-ray of osteoporosis show?
Fragility fractures
How is osteoporosis investigated?
X-ray DEXA scan (gold standard) - calculate FRAX score
What is the FRAX score?
Predicts risk of fragility fracture over next 10 years
What do the FRAX scores mean?
> -1 = normal
-1 > -2.5 = osteopenia
< -2.5 = osteoporosis
What lifestyle changes can be made to treat osteoporosis?
Quit smoking
Reduce alcohol consumption
Regular weight bearing exercise
Calcium and vitamin D supplements
What is the medical treatment for osteoporosis?
Bisphosphonates e.g. alendronic acid, IV zoledronate/zoledronic acid
Denosumab
HRT for early menopause
How should alendronic acid be taken?
Empty stomach, sitting upright for 30 minutes before moving or eating
What are the side effects of bisphosphonates?
Reflux and oesophageal erosions
What do bisphosophonates do?
Decrease osteoclast activity - slows down bone resorption and bone turnover
What is denosumab?
Monoclonal antibody to RANK ligand - inhibits osteoclasts
What are the seronegative spondylarthropathies?
Ankylosing spondylitis, psoriatic arthritis, reactive arthritis
What are the common fearures of seronegative spondylarthropathies?
SPINEACHE
Sausage digits (dactylitis) Psoriasis Inflammatory back pain NSAIDs - good response Enthesitis (heel) Arthritis Crohn's/UC/high CRP HLA B27 Eye - anterior uveitis/iritis
What are seronegative spondylarthropathies?
Group of inflammatory diseases of the spine and sacroiliac joints
What does ‘seronegative’ mean?
No rheumatoid factor
What is ankylosing spondylitis?
Chronic inflammatory disorder of spine and sacroiliac joints
What does inflammation in ankylosing spondylitis cause?
Pain and stiffness
What happens after healing of inflammation in ankylosing spondylitis?
Inflammation heals with new bone formation - syndesmophytes
How does ankylosing spondylitis present?
Lower back (sacroiliac) pain and stiffness Pain improves with exercise Pain worse at night - can wake patient Gradual onset of symptoms over >3 months Morning stiffness >1 hour
What are the effects on other organ systems in ankylosing spondylitis?
Chest pain - inflamed costosternal joints
Anterior uveitis
Enthesitis
Systemic symptoms (fatigue, fever, weight loss)
Dactylitis
Achilles tendonitis
What is the clinical examination of ankylosing spondylitis?
Schober’s test
What do bloods show for ankylosing spondylitis?
ESR/CRP raised
HLA B27 genetic test
What does an x-ray show for ankylosing spondylitis?
Bamboo spine - late stages of disease
What is the 1st line treatment of ankylosing spondylitis?
Exercise and physio
What is the 2nd line treatment of ankylosing spondylitis?
NSAIDs
What is the 3rd line treatment of ankylosing spondylitis?
Anti-TNF e.g. infliximab/etanercept
What is the 4th line treatment of ankylosing spondylitis?
Secukinumab - monoclonal antibody against IL-17
Where should you look for hidden psoriasis?
Behind ear Inside ear Scalp Nails Umbilicus Genitals
What is psoriatic arthritis?
Inflammatory arthritis associated with psoriasis (occurs in 10-20% of patients with psoriasis)
What are the different patterns of disease for psoriatic arthritis?
Symmetrical polyarthritis Asymmetrical oligoarthritis DIPJ arthritis Spondylitic arthritis Arthritis mutilans
How does symmetrical polyarthritis present?
Similar to RA
How does DIPJ arthritis present?
Dactylitis = characteristic
How does spondylitic arthritis present?
Similar to ankylosing spondylitis
What is arthritis mutilans?
Severe deformity where small bones in hands and feet are destroyed
How is psoriatic arthritis investigated?
PEST scoring tool
X-ray
What shows on x-ray for psoriatic arthritis?
‘Pencil-in-cup’ deformity
How is psoriatic arthritis managed?
NSAIDs for pain
DMARDS e.g. methotrexate/sulfasalazine
Anti-TNF drugs e.g. infliximab
What is reactive arthritis?
Sterile inflammation of synovial membranes, tendons and fascia
What triggers reactive arthritis?
Infection at a distant site
What infections can trigger reactive arthritis?
Gastroenteritis e.g. salmonella, shigella
STIs e.g. chlamydia (mainly), gonorrhoea
What does reactive arthritis typically cause?
Acute monoarthritis (knee = most common)
What differential must be excluded in cases of reactive arthritis?
Septic arthritis
What are the classic symptoms of reactive arthritis?
Can’t see - conjunctivitis
Can’t pee - urethritis
Can’t climb a tree - arthritis
What are the other symptoms of reactive arthritis?
Circinate balantis - painless ulceration of penis
Keratoderma blennorrhagia - feet
How do you investigate reactive arthritis?
Bloods - ESR/CRP raised
Culture stools if diarrhoea/STI swabs
Must aspirate joint + culture to exclude septic arthritis (if it is reactive arthritis it will be sterile)
How do you manage reactive arthritis?
Treat cause of infection with antibiotics
NSAIDs
Corticosteroid injections into affected joints
Consider systemic steroids if multiple joints affected
How long does it take for most cases of reactive arthritis to resolve?
Most cases resolve within 6 months. If they don’t, consider DMARDs/anti-TNF drugs
What joints does septic arthritis commonly affect?
90% monoarthritis
Knee > hip > shoulder
How do you test for septic arthritis?
Urgent joint aspiration - ideally aspirate before giving antibiotics
Gram stain and culture to help choose antibiotics
Polarised light microscopy to exclude gout/pseudogout
Fluid will be opaque/thick/pussy due to high WCC
What are the causes of septic arthritis?
Staph aureus - most common (in native joints)
Neisseria gonorrhoea if young/sexually active/MSM
Staph epidermidis if had a joint replacement
E. Coli/pseudomonas at extremes of age/IV drug users/immunocompromised
How is septic arthritis managed?
Urgent joint aspiration
Gram staining
Crystal microscopy
Culture
Antibiotic sensitivities
Don’t wait for culture results - treat empirically with IV antibiotics (IV flucloxacillin and rifampicin is often first line)
Antibiotics usually continued for 3-6 weeks
What is SLE?
Multisystemic inflammatory autoimmune connective tissue disease
Who is SLE most common in?
Pre-menopausal women
What is the pathophysiology of SLE?
Autoantibodies attack normal healthy proteins causing a chronic inflammatory response
What antibodies are associated with SLE?
Anti-nuclear antibodies (ANA) - low specificity, high sensitivity - can be +ve in healthy people/patients with other autoimmune conditions
Anti-double stranded DNA (anti-dsDNA) - highly specific for SLE but only positive in 60% of patients (low sensitivity)
How does SLE present?
SOAP BRAIN MD
Serositis (pleuritis, pericarditis) Oral ulcers Arthritis Photosensitivity Blood (all are low - anaemia, leukopenia, thrombocytopenia) Renal (protein) ANA Immunologic (dsDNA etc.) Neurologic (psych, seizures) Malar rash - photosensitive, butterfly shaped Discoid rash
How many of the SOAP BRAIN MD symptoms are needed to diagnose SLE?
4/11
What conditions is SLE associated with?
Antiphospholipid syndrome and Raynaud’s phenomenon
What are you at increased risk of if you have anti-phospholipid syndrome?
CLOTs
Coagulation defects - DVT, stroke
Levido reticularis - pink/blue mottling
Obstetric - recurrent miscarriages
Thrombocytopenia
How do you investigate SLE?
Bloods: Raised ESR/normal CRP Low complement (C3/4) Normocytic anaemia of chronic disease Autoantibodies - ANA/anti-dsDNA
How is SLE managed?
Sun cream and sun avoidance to prevent rashes
NSAIDs for analgesia
Hydroxychloroquine - first line for mild SLE
Prednisolone
Biological therapies if none of the above works
What are the different primary bone cancers?
Osteosarcoma
Ewing’s sarcoma
Chondrosarcoma
Chordoma
When does osteosarcoma normally present?
10-25 years
What is the most common bone affected in osteosarcoma?
Knee
What is found on x-ray for osteosarcoma?
Sunray spiculation
When does Ewing’s sarcoma normally present?
Under 30
What is the most common bone affected in Ewing’s sarcoma?
Femur and pelvis
What does x-ray show for Ewing’s sarcoma?
Onion skin appearance
When does chondrosarcoma normally present?
50+
What bone does chondrosarcoma normally affect?
Pelvis
What shows on x-ray for chondrosarcoma?
Popcorn calcifications
When does chordoma normally present?
50+
What bone is normally affected in chordoma?
Spine/skull
What are the most common cancers that metastasise to bone?
Breast Bronchus (lungs) Byroid (thyroid) Bidney (kidney) Brostrate (prostate)
How do bone tumours present?
Persistent bone pain Pain is worse at night - nocturnal pain Rest pain Localised redness/tenderness/swelling Restricted joint movements Unexplained bone fractures Fatigue/weight loss/fever
What are the back pain red flags?
TUNA FISH
Trauma - osteoporosis? Unexplained weight loss - cancer? Neurologic symptoms - cauda equina? Age >50 (secondary bone cancer?) or <20 (ankylosing spondylitis?) Fever - infection? IV drug use - infection? Steroid use - infection? History of cancer - metastases?
What are the cauda equina red flags?
Urinary incontinence (occurs because of loss of sensation when passing urine)
Urinary retention (loss of sensation of bladder fullness)
Saddle anaesthesia
Faecal incontinence
Decreased anal sphincter tone
Bilateral lower extremity weakness or numbness
Progressive neurological deficity:
- Major motor weakness - such as major motor weakness with knee extension, ankle eversion or foot dorsiflexion
- Major sensory deficit
What is mechanical back pain often related to?
Very common - often traumatic or work related
How does mechanical lower back pain present?
Lower back pain and stiffness worse on movement and improves with rest (opposite of inflammatory back pain)
Patient is systemically well
How do you investigate mechanical lower back pain?
No need to investigate unless chronic (>3 months) or red flags present
How long does it typically take for mechanical lower back pain to resolve?
90% resolve within 6 weeks
How is mechanical lower back pain treated?
Advise patient to continue normal activities and take pain relief if needed