MSK Flashcards
1
Q
Brief pathology of osteoarthritis
A
Degenerative progressive destruction of cartilage from repeated mechanical forces
Disruption of chondrocytes prevents rebuilding
Usually in synovial joints
2
Q
Why is obesity considered a pro-inflammatory state?
A
Bc it releases IL1, TNF and adipokines
3
Q
RF of osteoarthritis
A
Older age
High intensity labour
Joint hypermobility
Diabetes
F > M
Obesity
COL2A1 collagen type 2 gene plays a role
4
Q
Why is age a risk factor for OA?
A
Cumulative effect of traumatic insult and ↓ of neuromuscular function
5
Q
Main pathological features of OA
A
Loss of cartilage
Disordered bone repair
6
Q
Key Presentation - OA
A
Painful joints, stiffness < 30 mins in morning
Worse throughout the day
Occurs at PIP (Bouchard) and DIP (Heberden)
7
Q
What effects do oestrogen have on bone turnover?
And hence, what is a RF for MSK diseases e.g. osteoporosis, OA?
A
Oestrogen has restraining effect on bone turnover
∴ EARLY MENOPAUSE results in ↓ trab. Th, strength and bone connections
8
Q
List 4 other signs/symptoms of OA
A
Joint pain on movement
Tenderness
Crepitus
Asymmetrical joint involvement
9
Q
Ix Osteoarthritis
A
XRAY - LOSS
Loss of joint space
Osteophytes
Subchondral sclerosis (more white on XR)
Subchondral cysts
10
Q
DDx OA
A
RA
Gout
Psoriatic arthritis
11
Q
Tx OA
A
1. Px education & lifestyle changes
(weight loss if obese, physiotherapy, occupational therapy)
2. Analgesic ladder
a). Paracetamol, topical NSAIDs, topical capsaicin
b). Oral NSAIDs (+ PPI)
c). Opiates e.g. codeine, morphine
also, intra-articular steroid injections - hyaluronic acid
If extreme, joint replacement
(avoid steroids before surgery bc immunosuppressive)
12
Q
What type of hypersensitivity reaction is RA?
A
Type III
13
Q
RF RA
A
Female! (premenopausal women 3x more affected than men)
HLA-DR4 and HLA-DRB1 (more susceptible, associated w/ ↑ severity)
FHx
Stress
Infection
Smoking
14
Q
What are the diagnostic criteria for RA?
A
Need 4/7 to be diagnostic
Rheumatoid nodules
Rh factor POS
Radiographic changes (XR LESS)
Arthritis of hand joints
Morning stiffness > 30 mins
Symmetrical
15
Q
State and describe hand deformities found w/ RA
A
Ulnar deviation
Boutonniere deformity - PIP flexion, DIP hyperextension
Swan neck deformity - PIP hyperextension, DIP flexion
16
Q
State 10 other signs/symptoms of RA
A
Digital infarcts along nail bed
Anaemia - normochromic/cytic
Palpable lymph nodes
Bursitis
Tenosynovitis
Warm, red, tender joints
Joint pain worse in mornings/cold
Loss of function
Popliteal cyst
Rheumatoid nodules at pressure points
Sicca
Carpal tunnel syndrome
Fatigue and malaise
Symmetrical
DIPs are usually spared!
17
Q
Ix RA
A
FBC/Bloods
Rh factor POS (sensitive)
Anti-CCP POS (specific, not routine)
↑ ESR, ↑ CRP, ↑ Platelets
XR - LESS
Loss of joint space
bone Erosions
Soft tissue swelling
Soft bones (osteopenia)
Genetic testing
18
Q
State some extra-pulmonary manifestations of RA
A
Caplan’s syndrome (esp in coal miners)
Felty’s syndrome
Anaemia of chronic disease
Lymphadenopathy
2° Sjogren’s syndrome
Amyloidosis
19
Q
DDx RA
A
Psoriatic arthritis
OA
Symmetrical seronegative spondyloarthropathies
20
Q
Tx RA
A
MDT treatment!
- NSAIDs (+PPI)
Steroids initially, for flare ups to settle - DMARDs e.g. methotrexate, leflunomide, sulfasalazine hydroxychloroquine (mildest DMARD ∴ preferential if disease isn’t too severe)
a) one of above
b) 2 of above
c) Methotrexate + TNF inhibitor
d) Methotrexate + biologic e.g. Rituximab
21
Q
Remember :
A
OA less convincing response to NSAIDs than RA
RA - worse w rest, better w movement. OA is opposite
RA - symmetrical, OA - not
22
Q
At what age, is the peak bone mass?
A
29 years
23
Q
State 1° causes of osteoporosis
A
Post-menopause
Age
bc oestrogen protects bone!
24
Q
State 2° causes of osteoporosis
A
SHATTERED
Steroid use
Hyperthyroidism/hyperparathyroidism
Alcohol/Smoking
Thin (low BMI < 22)
Testosterone low
Early menopause
Renal or liver failure
Erosive / inflammatory bone disease
Dietary calcium low
25
Key presentation of osteoporosis
Fractures!
Esp if happens when/where it shouldn't happen
26
Ix Osteoporosis
**DEXA Scan** BMD measurement
T score (esp at hip)
(then compared against gender-matched YA average)
> -1 normal
Between -1 and -2.5 = Osteopenia
**<-2.5 = Osteoporosis**
ALSO : FRAX score - 10 year probability of major fracture
27
When ↓ seru Ca2+,
Parathyroid gland secretes PTH
∴ ↑ bone resorbtion and Ca2+ released into blood stream
28
When ↑ serum Ca2+,
Parathyroid gland produces calcitonin,
inhibits PTH secretions,
↑ bone formation and Ca2+ absorbed from bloodstream
29
What happens to trabecular architecture with age?
↓ Trab Th
↓ Connections between horizontal trabeculae
∴ ↓ Trab strength (∴ ↑ risk of fractures)
30
Why are horizontal trabeculae so important?
Makes bones a LOT stronger
Eular-Buckling theory
31
During bone turnover due to oestrogen deficiency, what type of bone is mostly lost?
Cancellous bone
32
What occurs if there's too much mineralisation in bones?
Become stiff and shatter
33
What occurs if there's too little mineralisation in bones?
Bones aren't strong and break
34
What occurs if there's too little mineralisation in bones?
Bones aren't strong and break
35
What do bloods show in osteoporosis?
Ca2+, phosphate, alkaline phosphate are all normal
36
Tx Osteoporosis
**Lifestyle changes** - Avoid falls!!
Quit smoking, ↓ alcohol, healthy weight
Adcal D3 (Vit D + Calcium)
1. **Oral bisphosphonate** (↓ osteoclastic activity)
e.g. alendronate (10mg daily), risendronate (5mg daily)
2. Denosumab or Strontium ranelate or Teriparatide
ALSO : consider Hormone Replacement Therapy in young post-menopausal women
37
What does ESR stand for?
Erythrocyte Sedimentation Rate
38
Define ESR
Measure of how quickly erythrocytes will fall to bottom of tube
39
What does ESR measure?
Fibrinogen values
Rise w/ inflammation bc erythrocytes stick together and ∴ fall faster
40
How does ESR rise and fall?
Rises and falls SLOWLY (days to weeks)
41
What causes ESR to rise falsely? (False positives)
Female
Age
Obesity
SE Asian
Hypercholestrolaemia
High Immunoglobulin (myeloma)
42
Full form of CRP
C-Reactive Protein
43
Define CRP
Acute phase protein, released in inflammation
44
Where is CRP produced?
In liver in response to IL-6
45
How does CRP rise and fall?
QUICKLY - high at 6 hours, peaks at 48 hours
∴ if patient has infection in 24 hours, ESR won't have risen but CRP will have
46
SPINEACHE go
Sausage digit (dactylitis)
Psoriasis
Inflammatory back pain
NSAID good response
Enthesitis (heel)
Arthritis
Crohn’s / Colitis / ↑CRP (but CRP can be normal)
HLA B27
Eye (uveitis)
47
What joint do Spondyloarthropathies typically affect?
Spinal and sacroiliac joints
48
Spondyloarthropathies are _____
seronegative (no RhF)
49
HLA-B27 encoded by
Major histocompatibility complex on chromosome 6
50
Why does HLA-B27 cause disease?
Causes autoimmune disease by **molecular mimicry**
Infection occurs and infection agents have peptides v similar to HLA-B27
∴ immune system launches attack on HLA-B27
51
Epidemiology of Ankylosing Spondylitis
*More common and severe in Males
*Presents in late teens/20s
↓ Incidence in African and Japenese people
Native NA ↑ incidence
52
Ix Ankylosing Spondylitis
Bloods -
HLA-B27 positive
↑ CRP, ↑ ESR
Normocytic anaemia
XR
MRI
Schober's test!
53
Why can you perform an MRI for ankylosing spondylitis?
Bc before bamboo spine, bone marrow oedema occurs first - showed by MRI
54
What XR signs are there in Ankylosing spondylitis?
Sacroiliitis
Enthesitis
Dagger sign
Syndesmophytes
**BAMBOO SPINE**
55
Ankylosing Spondylitis, diagnose if :
Age at onset < 45 years
At least 3 months back pain
XR/MRI shows sacroiliitis + at least 1 SPINEACHE feature
56
State some other signs/symptoms of Ankylosing Spondylitis
Worse with rest
Slow onset morning stiffness > 30 mins
Fatigue
Buttock/thigh pain - sacroiliac joints
Rashes/skin changes
57
Describe Schober's test
Make a point at L5
Put a finger 10cm above and 5cm below
Px bends forwards
If distance between 2 fingers is < 20 cm, supports a diagnosis of Ankylosing Spondylitis
58
Rf for Ankylosing Spondylitis
HLA-B27!
Environment : Klebsiella, Salmonella, Shigella
59
Differences between Ankylosing Spondylitis and RA
RA affects smaller joints and is usually symmetrical
AS affects spine and is asymmetrical
60
Is HLA-B27 diagnostic for ankylosing spondylitis?
NO!
61
Red flags for back pain
**TUNA FISH**
**T**rauma, TB
**U**nexplained weight loss & night sweats
**N**eurological deficits, bowel/bladder incontinence
**A**age <20 and > 55
**F**ever
**I**VDU
**S**teroid use or immunosuppressed
**H**istory of cancer, early morning stiffness
62
What is Scleroderma?
Multi-system disease w/ involvement of skin. Vascular damage (fibrosis) of small arteries, arterioles and capillaries.
63
Epidemiology of Scleroderma
Female!
30 - 50 years
Rare in children
64
RF Scleroderma
Exposure to vinyl chloride, silica dust, rapeseed oil, trichloroethylene
Drugs - bleomycin
Genetics
65
Types of Scleroderma
1. Diffuse - CREST + organ problem
2. Limited - just CREST
66
What are the FIRST symptoms usually in Scleroderma?
Raynaud's
Sclerodactyly
67
Ix Scleroderma
**Bloods** - norm anaemia
RhF+
For limited : Anti-centromere antibodies
For diffuse : Anti-topoisomerase-1 (anti SCL-70) antibodies & anti-RNA polymerase III
CXR - exclude other causes
Hand XR - see calcium deposits
Barium swallow - confirm oesophageal dysmotility
68
What systemic effects can Scleroderma have?
GI - heartburn, dysphagia, malabsorption, pseudo-obstruction
Renal - AKI, CKD, acute hypertensive crisis
Lung - fibrosis, pul HTN
Heart - arrhythmias
69
Tx Scleroderma
No cure. Immunosuppressants used to slow progression - cyclophosphamide
MDT - physio
Treat symptoms
Raynaud's : vasodilators - nifedipine
Analgesia
PPI for reflex
Pul HTN - sildenafil
etc
70
Prognosis Scleroderma
~ 12 years after diagnosis (avg)
However, if limited, could have normal lifespan
71
Complications of Sjorgren's
B-Cell lymphoma !!!!!!
72
A patient comes in with a red, hot, swollen joint. What do you do?
ASPIRATE IT ALWAYS !!!!!!!!!!!!!!
COULD BE SEPTIC ARTHRITIS
73
Causes of Septic arthritis
**S. Aureus**
Neisseria gonorrhoea - sexually active, young
Staph. Epidermis - prosthetic joint
E.coli / Klebsiella - immunocomp
H. influenzae - infants, but rare bc immunisation now
74
RF Septic Arthritis
> 80 years, infants (always suspect in ANY joint problem in children)
Pre-existing joint disease
DM
Prosthetic joints
Immunosuppress
Penetrating trauma
75
Key presentation Septic Arthritis
*Knee, hip, shoulder
Acute, painful, red, hot, swollen joint
SEPTIC UNTIL PROVEN OTHERWISE
76
Other signs/symptoms of septic arthritis
Fever
Impaired range of motion
Refusing to bear weight
Monoarthritis
77
Ix Septic Arthritis
ALWAYS ASPIRATE FIRST -> GS !!
FBC - ↑ WBC, neutrophilia
Blood cultures
Polarised light microscopy - exclude gout/pseudogout
78
What would you see in the aspirate of a patient with Septic Arthritis?
Turgid fluid - non-transparent
Leukocytes
Send for gram-stain
Normal = yellow, clear, thin
79
Why is Septic Arthritis a medical emergency?
Can destroy joint in under 24 hours !!!!!!!!
80
Tx Septic Arthritis
Stop immunosuppressive drugs (e.g. methotrexate) and anti-TNF for as long as on Abx
ANTIBIOTICS !
Empirical e.g. flucloxacillin
then pathogen-directed, 3-6 weeks
(IF on steroids, double dose. If not, then don't give steroids)
81
What Abx against S. Aureus?
Flucloxacillin
Erythromycin
Doxycycline
Tetracycline
82
Causes of Osteomyelitis
**Staph. Aureus**
Salmonella - if sickle cell anaemia
Staph - coagulase neg (epsa)
H. influenzae
83
How does bacteria reach the joints to cause septic arthritis?
Direct inoculation or via haematogenous spread
84
Key presentation of OM
Dull pain at site of OM
Onset - several
Non-specific tenderness and pain
Reluctance to weight bear
85
Name some systemic symptoms of OM
Fever
Rigors
Sweat
Malaise
86
Ix OM
FBC - ↑ ESR, ↑ CRP, ↑ WBC, but can be normal in chronic
XR - can see periosteal reaction, low sensitivity/specificity for OM i.e. cannot exclude
**GS :** Bone biopsy (but must be done thru not infected tissue)
MRI - best imagine to establish diagnosis
must be done after XR
Blood cultures
87
Tx OM
Antibiotics - tailored to culture
If vascular disease, less reliable Abx penetration ∴ longer duration
Surgery if severe
88
DDx OM
Charcot joint! - damage due to sensory nerves affected by DM
Gout
Fracture
89
Ix Psuedogout
Joint aspirate and polarised light - rhomboid crystals, positively birefringent, no bacterial growth
**GS :** XR - Chondrocalcinosis
90
Hidden sites for psoriasis
Behind ear/inside ear
Scalp
Pitting in nails/ onokylisis
Umbilicus
Penile
Natal cleft
91
State the types of Psoriatic Arthritis
5 patterns of disease
1. Asymmetrical oligoarthritis
2. Symmetrical seronegative polyarthritis
3. Spondylitis
4. Distal interphalangeal arthritis
5. Arthritis mutilans
92
Describe symmetrical polyarthritis
Females
Hands, wrists, ankles and DIP joints
MCP less common (∴ unlike RA but otherwise v similar)
93
Describe asymmetrical oligoarthritis
Mainly fingers, toes and feet
Only a few joints
94
Describe spondylitic psoriatic arthritis
Males
Back stiffness, sacroiliitis, alanto-axial joint involvement.
Can also affect - spine, achilles tendone, plantar fascia
95
Key presentation of Psoriatic Arthritis
Plaques of psoriases - in hidden areas
Onycholysis
Dactylitis
Enthesitis
96
Ix Psoriatic Arthritis
Bloods - HLA-B27, ↑ ESR
NEG RhF and NEG anti-CCP
**GS :** XRAY
Erosion in DIP, periarticular new bone formation
Oateolysis
Pencil-in-cup deformity
97
Tx Psoriatic Arthritis
Similar to RA -
NSAIDs
DMARDs - methotrexate, sulfasalazine, leflunomide
TNF-i or monoclonal antibodies - etanercept, infliximab, adalimumab
Steroid injection
Physio
98
Complications of Psoriatic Arthritis
**Arthritis mutilans**
Most severe form
Occurs in phalanxes
Osteolysis of bones around joint - causes progressive shortening
Skin folds as digit shortens - telescopic finger
99
Ix Anti-phospholipid Syndrome
Anti-cardiolipin antibody test
Anti-B2-glycoprotein test
Lupus anticoagulant test
^ All 3 are needed to diagnose
Positive test on at least 2 ocassions 12 weeks apart
100
What does the anti-cardiolipin antibody test test for?
IgG or IgM antibodies that bind to cardiolipin (neg charged phospholipid)
101
What does the lupus anticoagulant test detect?
Changes in ability of blood to clot
102
Tx Anti-Phospholipid Syndrome
Manage risk factors e.g. smoking
Long term warfarin (LMWH if trying to conceive)
Prophylaxis e.g. for stroke - aspirin or clopidogrel
103
Anti-Phospholipid Syndrome causes
**CLOTs**
**C**oagulation defect
**L**ivedo reticularis
**O**bstetric issues
**T**hrombocytopenia
104
Key presentation of Anti-Phospholipid Syndrome
Thrombosis !!!!!!!!!
e.g.
Arteries - stroke, MI, TIA
Veins - Budd-chiari syndrome, DVT, PE
Miscarriage !!
105
Cause of Anti-Phospholipid Syndrome
**HLA-DR7 mutation + Environmental trigger**
e.g. infection (malaria), drugs (CV drugs - propranolol, anti-psychotic - phenytoin)
106
How soon after an infection do clinical signs of reactive arthritis occur?
1-4 weeks
107
What is small vessel vasculitis called?
Granulomatosis with Polyangiitis
aka Wegener's Granulomatosis
108
RF Psuedogout
Females > 70years
Hyperthyroidism
Hyperparathyroidism
XS iron or calcium
109
RF Gout
Middle-age
Overweight
High purine diet (red meat, seafood)
Alcohol
Diuretics
FHx
Renal disease/existing CVD
110
RF RA
Middle age
Female! (3x more common)
FHx
Other autoimmune diseases
111
RF OA
High intensity labour
Older age
Obesity
Trauma
Female
FHx
112
What vessels does Giant Cell Arteritis affect?
Aorta and/or its major branches (carotid and vertebral arteries)
Often temporal artery!
113
RF Giant Cell Arteritis
> 50 years
Northern European
Females! (2-3x more common)
Hx of polymyalgia rheumatica
(RA, SLE, scleroderma)
114
Key presentation of Giant Cell Arteritis
Headache! new onset, unilateral over temporal area
Scalp tenderness (hurts to brush hair)
115
Other signs/symptoms of Giant Cell Arteritis
Jaw claudication
Visual disturbances! - blurred vision, diplopia, amaurosis fugax, blindness
On palpitation, temporal arteries tender and thickened
Pulse may be diminished
116
What type of vessels does Takayasu's arteritis affect?
Large
117
What type of vasculitis affects medium-sized vessels?
Polyarteritis nodosa (PAN)
118
What type of vasculitis affects small vessels?
Granulomatosis with polyangiitis
119
Ix Giant Cell Arteritis
Bloods - ↑ ESR +/- ↑ CRP (v sensitive)
ANCA neg
ESR > 50 mm/hour
Ultrasound - Halo sign of temporal and axillary artery
**GS :** TEMPORAL ARTERY BIOPSY
shows giant cells, granulomatous inflammation
120
Tx Giant Cell Arteritis
High dose prednisolone (40-60mg) then gradual reduction
Long-term (12-18 months) ∴ give GI and bone protection -> Lansoprazole, alendronate, Ca2+, Vit D
if visual change - emergency! IV methylprednisolone
121
What locations does Polyarteritis Nodosa occur?
Medium muscular arteries, esp at branch points
Skin, GI tracts, kidneys, heart
NOT veins
122
RF Polyarteritis Nodosa
Associated with **Hep B**! (and Hep C, HIV)
More common in LICs
123
DDx Giant Cell Arteritis
Migraine
Tension headache
Trigeminal neuralgia
Polyarteritis nodosa
124
Presentation of Polyarteritis Nodosa
Cutaneous/subcutaneous nodules
Unilateral orchitis
Peripheral neuropathy - mononeuritis
Abdo pain
Livedo reticularis
HTN
125
Ix Polyarteritis Nodosa
Bloods - ↑ ESR +/- ↑ CRP
HBsAG
ANCA neg
Biopsy - transmural fibrinoid necrosis
126
Tx PAN
If Hep B neg - corticosteroids + immunosuppressant (cyclophosphamide)
If Hep B pos - corticosteroids, then antivirals, plasma exchange
Control BP - ACEi
127
Complications PAN
GI perforation & haemorrhages
Arthritis
Renal infarcts
Strokes
MI
128
Age of presentation of Granulomatosis with Polyangiitis
Late teenage years - early adulthood
129
Key presentation of Granulomatosis with Polyangiitis
**Saddle shaped nose**
Epistaxis (nosebleed)
Crusty nasal/ear secretions - hearing loss
Sinusitis
Cough, wheeze, haemoptysis
130
DDx Granulomatosis with Polyangiitis
Pneumonia (esp bc cough, wheeze, haemoptysis)
131
Ix Granulomatosis with Polyangiitis
Bloods - ↑ Eosinophils
**c-ANCA** !!!!!!!!!!
Histology - granulomas
132
Tx Granulomatosis with Polyangiitis
Corticosteroids
Cyclophosphamide
133
Complications of Granulomatosis with Polyangiitis
Glomerulonephritis
134
Describe Churg-Strauss
**P-ANCA**
No nasopharyngeal involvement
No granuloma
Small vessels?
check
135
Paget's disease
Raised ALP
136
Ix Sjogren's
**Anti-Ro** and **Anti-La antibodies**
Schirmer's test
137
Tx Sjogren's
Artificial tears, artificial saliva, vaginal lubricants
Hydroxychloroquine used to halt progression
138
What is Sjogren's?
Autoimmune condition that affects exocrine glands
139
Difference between primary and secondary Sjogren's
1º - condition occurs in isolation
2º - related to SLE or RA
140
RF Sjogren's
FHx (first degree relative = 7x higher risk)
Female
> 39 years
