MSK Flashcards
Function of type 1 collagen
Elasticity
Where is type 1 collagen found
Skin, tendon, organic component of bone
Where is type 2 collagen found
Cartilage
Where is type 3 collagen found
Connective tissue
Where is type 4 collagen found
Epithelial layer of Basement membrane
Where is type 5 collagen found
Hair
Placenta
Define ligaments
Bone - bone attachment
Define tendons
Muscle - bone attachment
Give an example of fibrous joints
Skull suture
- Immoveable
Give an example of cartilageneous joints
Intervertebral discs
- Partially moveable
Give an example of synovial joints
Most joints in the body
Knees, hips, fingers shoulder
- Moveable
Components / anatomy of synovial joints
Articular cartilage - Lines the end of the periosteum (bone part with pain receptors)
Joint capsule - Inner lining of the synovial membrane
Joint cavity filled with synovial fluid
Define osteoarthritis
Most common arthritis
Non-inflammatory, degenerative mechanical shearing of synovial joints
Risk factors for osteoarthritis
Increased age (50+ ; women >50 affected a lot)
Obesity
Occupation / sports
Genetics (COL2A1; genetic predisposition)
Pathophysiology of osteoarthritis
Imbalanced cartilage breakdown > repair
Where you get increased chrondrocyte metaleoproteinase secretion
Degrades collagen type 2 + forms cysts
Bone attempts to overcome with type 1 collagen but get abnormal bony growths (osteophytes) + remodelling
Signs and Sx of osteoarthritis
Transient (< 30/60 mins) morning pain —> worsen as day goes on
Heberdens + Bouchard’s nodes on fingers
Assymetrical, hard non-inflamed joints
No extra-articular Sx
Crepitus - crackling or grating sensation when moving a joint
In which condition are heberdens nodes found and where in the body
Distal interphalangeal joints
Osteoarthritis
In which condition are bouchards nodes found and where in the body
Found in proximal interphalangeal joints
- osteoarthritis
Investigation and Dx of osteoarthritis
Xray changes:
Loss of joint space
Osteophytes
Subchondral cysts
Subchondral sclerosis
Bloods - normal
Tx for osteoarthritis
Lifestyle management:
Weight-bearing, physio
Medical:
1st line - Paracetamol + topical NSAIDs
2nd line - Oral NSAIDS + PPIs ± topical capsaicin (chilli pepper extract)
Consider
Last resort - Arthroplasty
Define rheumatoid arthritis
Inflammatory autoimmune symmetrical polyarthritis
Who does RA affect more
Women
30-50y/o
x3 more likely than males; pre menopause
Post menopause - m=f
Risk factors for rheumatoid arthritis
Women >
Age
Smoking
Genetics - HLADR1 + 4
Pathophysiology of rheumatoid arthritis
Arginine —> citruline mutation in type 2 collagen
Anti-CCP (cyclic citrullinated peptide) formation against citrullinated molecules.
TNFa causes further pro-inflammatory recruitment to synovium
- synovial lining expands and tumour-like mass (pannus) grows past joint margins
- Pannus destroys subchondral bone + articular cartilage
Signs and symptoms of rheumatoid arthritis
Morning stiffness > 30/60mins (eases as day goes on)
Boutenieres deformity
Swans neck deformity
Ulnar deviation
Z-thumb deformity
Remember as an anomaly; DIP joints are often spared, unlike psoriatic arthritis.
Bakers cyst might occur behind knee when the inflamed synovium moves posterior creating a cyst
Symmetrical, hot, inflamed joints
What extra-articular complications are seen in rheumatoid arthritis
Lungs - pulmonary fibrosis
Skin - rheumatoid skin nodules
Heart - increased IHD risk
Eyes - Episcleritis
Define felty syndrome
Triad of: rheumatoid arthritis, granulocytopenia, splenomegaly
Life-threatening; high risk of infection
Investigation and Dx of rheumatoid arthritis
Bloods:
Increased CRP & ESR (Used for monitoring disease)
Normacytic normochromic anaemia (chronic disease)
Serology:
+ve Anti-CCP (80%; specific), +ve rhematoid factor (non-specific)
Xray:
Loss of joint space
Erosions
Soft tissue swelling
Soft bones (osteopenia)
Tx for rhematoid arthritis
First line is monotherapy with methotrexate (gold standard), leflunomide or sulfasalazine.
Hydroxychloroquine can be considered in mild disease and is considered the “mildest” anti rheumatic drug.
Second line is 2 of these used in combination.
Third line is methotrexate plus a biological therapy, usually a TNF inhibitor - influximab
Fourth line is methotrexate plus rituximab - B-cell inhibitor; CD20 target
Flare-up management
NSAIDs (1º care analgesia) - ibuprofen + Glucocorticoids injections
Classification used to Dx rheumatoid arthritis
ACR
American College of Rheumatoid Arthritis
Or
EULAR
European League Against Rheumatism
Tx for RA flare ups
NSAIDs (1º care analgesia) - ibuprofen + Glucocorticoids injections
Which score is used to assess RA management
DAS28
Disease activity score 28
Define gout
Gout is an inflammatory arthritis caused by deposition of monosodium urate crystals within joints.
Who does gout typically affect
Middle aged overweight men
Which joint is most affected in gout
first metatarsophalangeal joint (MTP).
Base/bottom of big toe
Pathophysiology of gout
Urate is a metabolite of purine synthesis
Purines ————> uric acid ————> monosodium urate
I
I
Xanthine Oxidase
Uric acid is usually excreted via kidneys but if there’s impaired excretion (CKD) OR over-production… causes gout
Hyperuricaemia increases risk of gout but not guaranteed for getting gout
Risk factors for gout
Purine rich diets: fish/seafood, meat, beer
Dairy can be Anti-gout
CKD
Diuretics
Signs and Sx of gout
Mono-articular; big toe typically (metotarsophalangeal joint)
- *sudden onset, hot, swollen red toe. Can’t put weight on it.
Gouty tophi - nodular masses of urate crystals form, usually as a late complication
Differential diagnosis for gout
Septic arthritis
Investigation and Dx of gout
Joint aspirate + polarised light microscopy - gold standard
* Needle-shaped, Negative bifringement monosodium urate crystals.*
Xray:
Punched out erosions
Lytic lesions - sclerotic borders with overhanging edges
Tx for gout
1st line: NSAIDs (+ PPIs)
2nd line: Cholcicine
3rd line: corticosteroid intracellular-articular injection
Prophylaxis
Allopurinol - xanthine oxidase inhibitors - decreased uric acid conversion
Define pseudogout
The deposition of calcium pyrophosphate crystals in long bone joint capsules
Chondrocalcinosis
Who does pseudogout typically affect
Elderly females (> 70y/o)
Joints most affected in pseudogout
Knee
Shoulder
Hip
Wrist
Risk factors for pseudogout
Increasing age
Diabetes
OA
HyperPTH
Signs and Sx for pseudogout
Often polyarticular (knee commonly affected)
- Swollen, red, hot joint
Differential Dx for pseudogout
Septic arthritis
Investigation and Dx of pseudogout
Joint aspiration +polarised light microscopy:
Rhomboid shaped, Positive bifringement of calcium pyrophosphate crystals
Gold standard
Xray:
Chondrocalcinosis - white line inbetween the synovial joint
LOSS - same as osteoarthritis in Xray ∆
Tx for pseudogout
Only Acute management :
NSAIDs, then cholcicine, then corticosteroid injection
No prevention drug here!
Give examples of connective tissue disorders
Marfans
Ehlers danlos syndrome
Define marfans syndrome
Connective tissue disorder
- decreased connective tissue tensile strength
Inheritance pattern for marfans
Autosomal dominant
- mutation in FBN1
Signs and Sx of marfans
Marfans body habitus
- Tall and thin
- Long fingers (arachnodactyly)
- Pectus excavation / cannaturn (sternum pressed in / puffed cut)
+
AORTIC COMPLICATIONS -
AAA / aortic dissection
Aortic regurgitation murmur
Investigation / Dx for marfans
Clinical Px + FBN-1 mutation
Define ehlers donlos syndrome
Autosomal dominant mutations affecting collagen proteins
13ish subtypes
Signs and Sx of EDS
Joint hypermobility + CV complication (AAA / Aortic dissection ‘ Mitral regurgitation)
Investigation / Dx for EDS
Clinical + collagen mutations
THESE CONNECTIVE TISSUE DISORDER WILL MEAN WEAK VALVES, WEAK VESSELS
What could cause mechanical lower back pain
Normal between ages 20-55
Could be trauma / work related
Signs of serious pathology:
Elderly - could indicate myeloma / neuropathic pain (spinal cord compression)
Define lumbar spondylosis
Degeneration of intervertebral disc; loses its compliance + thins over time
Seen in older Px
Most commonly affects - L4/5 OR L5/S1
Tx: Analgesia + physiotherapy if simple mechanical pain
Structure of bone: what is the hard external layer
Cortical bone
Structure of bone: what is the internal layer of bone called
Spongy / trabecular bone
Structure of bone: Role of trabeculae
Structural beams giving support to the spongy / trabecular bone
Structure of bone: What is cortical bone made of
Small functional units - Osteons
Structure of bone: what allows blood supply to pass through hard bone
Osteons have a hollow canal - Haversian canal which allows blood vessels and nerve innervation to run through the bone
Structure of bone: what surrounds the Haversian canal?
Haversian canal is hole in osteon centre carrying blood supply etc….
Lamellae surrounds this and has an organic component - Collagen
And an inorganic component - hydroxyapatite (calcium phosphate)
Structure of bone: what’s found inbetween lamellae
Inbetween lamellae we find lacunae where bones cells (Osteocytes) are found
Steps of bone remodelling
Bone resorption
Osteoclast break down bone
Bone formation
Osteoblast form new bone
What does bone remodelling depend on
Serum calcium levels
- controlled by PTH, calcitonin and Vit D
When is calcitonin released
When serum calcium is too high… calcitonin secreted by thyroid gland.
- promotes bone formation and decreases bone resorption
Define osteoporosis
Reduced bone density resulting in porous bone with increased fragility
Difference between osteoporosis and osteomalacia
Reduction in bone density but no mineralisation in osteoporosis. But there is in osteomalacia
Who does osteoporosis mainly affect
50+ y/o postmenapausal Caucasian women
Risk factors for osteoporosis
Remember SHATTERED
Steroids / Smoking
Hyperparathyroid
Alcohol
Thin (reduced BMI)
Testosterone decreased
Early menopause
Renal failure
Erosive / inflammatory disease
DMT1
Signs and Sx of osteoporosis
Asymptomatic
Fractures may indicate it
• Vertebrae / compression fractures (may have kyphosis)
• Proximal femurs
• Colles’ (forked wrists - fallen on outstretched wrists)
Investigation and Dx of osteoporosis
DEXA scan - gold standard
Dual energy Xray Absorptiometry
- gives a T-score (comparing BMD of Px to reference)
frax tool - fracture risk assessment tool
Asses10yr fracture risk in osteoporotic Px
Which scan is used in osteoporosis
DEXA
Tx for osteoporosis
1st line: Bisphosphonates
Aledronate (aledronic acid)
Risondronate (Risodronic acid)
2nd line:
mAb - Denosumab
Hormone Replacement Therapy - oestrogen & testosterone
Oestrogen receptor modulator - Raloxafine
What is the range for dexa score and what condition is it used in
Used for osteoporosis
T score:
Normal: > -1
Osteopenia: between -1 and -2.5
Osteoporosis: < -2.5
Severe osteoporosis: < -2.5 + fractures
Define osteopenia
Osteopenia refers to a less severe reduction in bone density than osteoporosis
Why are bisphosphonates used in osteoporosis
Inhibit RANK-L signalling so osteoclast activity is inhibited
When is denosumab used
2nd line for osteoporosis
It’s a monoclonal antibody - inhibits RANK-L
Give examples of autoimmune rheumatological disorders
Systemic lupus erythmatosis
Antiphospholipid syndrome
Sjogren syndrome
Scleroderma
Polymyositis
A 30-year-old African-American lady presents to her GP with increasing fatigue and joint pain. On examination, she has a butterfly rash across her face. What is the Dx?
Systemic lupus erythmatous
Define SLE
Type 3 hypersensitivity reaction - autoimmune systemic inflammation due to Antigen:Antibody complex deposition.
Who is SLE typically seen in
Females
Afrocarribean descent
20-40y/o (premenopausal)
Risk factors for SLE
Female (12x more than M)
HLADR2/3 or HLAB8
Drugs
Environmental factors - UV rays
Pathophysiology of SLE
Damage to cells leading to impaired apoptosis. Apoptotic debris is presented to Th2 Cell Especially nuclear antibodies and double-stranded DNA
—> B cell activation —> antigen-antibody complexes deposition in tissue.
SO, SLE can be characterised by Anti-Nuclear Antibodies (ANA) and anti-dsDNA
Signs and Sx of SLE
Malar butterfly rash on face + photosensitivity
Glomerulonephritis (Nephritic syndrome)
Mouth ulcers
Reynauds phenomenon
Joint pain
Investigation and Dx for SLE
FBC: INCREASED ESR NORMAL CRP
Serology:
ANA +ve - v. Sensitive
Anti-dsDNA - v. Specific (Also used to monitor SLE progression)
Essentially diagnostic using these
Reduced C3+C4: Due to active disease
Prolonged APTT: in lupus Px is hypercoaguable
Tx for SLE
Lifestyle changes: reduced uv ray exposure / reduce triggering drugs
1st line:
Corticosteroids - prednisolone
Then:
+ Hydroxychloroquine (DMARD)
+ NSAIDs
+ immunosuppressant if severe (Azathioprine)
Note: Aim is to taper off the other drugs so Px is left with hydroxychloroquine once stable
Define Antiphospholipid syndrome
Syndrome characterised by thrombosis, pregnancy complications (recurrent miscarriages) and Antiphospholipid antibodies
Can be 1º (idiopathic ) or 2º (to other autoimmune conditions - especially SLE)
Who’s affected in Antiphospholipid syndrome
Females
Signs a and Sx of Antiphospholipid syndrome
CLOTS
- Px is in hyper-coaguable state
- venous thrombosis (DVT / PE)
- arterial thrombosis (stroke, MI, renal thrombosis)
Livedo reticularis - purple discolouration of skin
Investigation and Dx of Antiphospholipid syndrome
Sx + Hx of thrombosis etc… + persistent antibodies presentation
Lupus anticoagulant
Anticardiolipin antibodies
Anti-beta-2 glycoprotein I antibodies
Which antibodies seen in lupus
Lupus anticoagulant
Anticardiolipin antibodies
Anti-beta-2 glycoprotein I antibodies
Tx for Antiphospholipid syndrome
1st line: Warfarin long-term if Px had a thrombus
If pregnant give LMWH + aspirin
Prophylaxis: Aspirin - if not had a thrombus formation yet
Define Sjogren syndrome
Dry! Dry! Dry! - autoimmuneexocrine gland dysfunction
1º Sjogren’s is where the condition occurs in isolation.
2º Sjogren’s is where it occurs related to SLE or rheumatoid arthritis.
Which antibodies is Sjogrens related to
It is associated with anti-Ro and anti-La antibodies.
Signs or Sx of Sjogrens
Dry eyes, mouth and vagina
What test is used in Sjögren’s syndrome
Schirmer test - induce tears + and place filter paper under eyes.
Measure the travel of the tear (< 10mm = sjogrens)
Should be 20mm+
Tx for sjogrens
Artificial tears, saliva + lubricant for sexual activity
Sometimes can give hydroxychloroquine
What condition does Sjogrens directly increase the risk of
Lymphomas
Give examples of 1º bone tumours
Osteosarcoma
Ewing’s sarcoma
Fibrosarcoma
Chondrosarcoma
SECONDARY BONE TUMOURS
Osteolytic: Breast and Lung
Osteosclerotic: Prostate, Thyroid, RCC
+ myeloma - can cause back pain; old CRAB
What is the most common 1º bone malignancy
Osteosarcoma
Px: 15-19y/o
What condition is osteosarcoma associated with
Paget’s disease
Where does osteosarcoma most commonly metastasise to
Lungs
Xray signs of osteosarcoma
Sunburst appearing bone
Define ewings sarcoma
From mesenchymal stem cell
Affects 15y/o
Define chondrosarcoma
Malignancy of cartilage
Tx for bone tumour
Chemo/radiotherapy
Bisphosphonates
Define osteomalacia
Defective bone mineralisation
- before epiphyseal fusion : rickets
- after epiphyseal fusion : osteomalacia
Main cause of osteomalacia
Vitamin D deficiency
- reduced a calcium and phosphate
- reducing hydroxyapatite mineral of bone
Causes of osteomalacia
Vit d deficiency
HyperPTH
CKD
Liver failure
Anticonvulsant drugs - increased CYP450 metabolism of Vit d
Sx of osteomalacia
Fractures
Proximal weakness
Rickets:
Skeletal deformities
- bowed legs
- wide epiphysis
Investigation and Dx of osteomalacia
BM biopsy (gold standard)
Incomplete mineralisation
Bloods:
Decreased 25-hydroxyVitamin D
Increased PTH (low Vit D —> low Ca2+ —> increased PTH —>2º hyperPTH)
Raised ALP
XRay:
Loser’s zones (defective mineralisation - low-density bone surrounded by sclerotic borders)
Tx for osteomalacia
Calcitriol - Vit D replacement
Increase dietary intake - supplements / eggs
Define vasculitis
Inflammation of the blood vessels
There’s many types affecting different sized vessels leading to different damage depending on the tissue being supplied.
Types of vasculitis affecting small blood vessels
Henoch-Schonlein purpura
Eosinophilic Granulomatosis with Polyangiitis (Churg-Strauss syndrome)
Microscopic polyangiitis
Granulomatosis with polyangiitis (GPA - Wegerners disease)
Types of vasculitis affecting medium blood vessels
Polyarteritis nodosa
Buergers disease
Kawasaki Disease
Types of vasculitis affecting large blood vessels
Giant cell arteritis
Takayasu’s arteritis
Define giant cell arteritis
Aka temporal arteritis
As it typically presents in temporal artery…
So Px presents with… unilateral temple headache, jaw claudication, vision ∆ leading to vision loss - affecting a 50+ y/o Caucasian female.
Key complication of giant cell arteritis
Vision loss - sudden and painless
Usually in one eye
If temporary - may cause Amourosis fugax (more typically seen in TIA)
May become permanent if not treated ASAP -
High dose IV METHYLPREDNISOLONE
Give general Sx of vasculitis
Fever
Weight loss
Fatigue
Muscle aches
Investigation and Dx of GCA
1st line:
Raised ESR ± CRP
Diagnostic:
Temporal artery biopsy: Multinucleated giant cells (Hence its name GCA) - seen as granulomatous inflammation of intima and media.
Note: GCA presents as skip lesions so take a bigger chunk for biopsy
Which condition presents with raised ESR normal CRP
SLE
Tx of giant cell arteritis
Corticosteroids - Prednisolone
±
Aspirin - decreases visual loss and strokes
PPIs - for gastric damage prevention
What’s Takayatsu disease
Similar to GCA but Aorta is affected more in this condition, not temporal vessels.
May get arm claudication or syncope - use Doppler USS to see carotids or CT/MRI angiography
Define polyarteritis nodosa
Medium vessel vasculitis
Associated with Hep B.
Immune cells affect endothelium lining of medium vessels leading to transmural inflammation —> overtime all 3 layers die (Fibrinoid necrosis) —> wall is therefore weakened leading to Aneurysms
Signs and Sx of polyarteritis nodosa
Severe systematic Sx:
GI bleeds
CKD / pre-renal AKI
Subcutaneous skin nodules + haemorrhage
Get Livedo reticularis - rash
Investigation and Dx of polyarteritis nodosa
Ct angiogram- Beads on string (micro aneurysms) - looks like a tasbeeh [ -o-o-o-o- ]
Biopsy of affected area
Tx of polyarteritis nodosa
Corticosteroids - prednisolone
Controls htn —> ACEi
Tx Hep B after
Which vasculitis is c ANCA +ve
Granulomatosis with PolyAngitis i.e.
wegeners granulomatosis
Classic sign for wegeners granulomatosis
Saddle shaped nose
- may also cause glomerulonephritis / pulmonary renal syndrome
Define henloch schonlein purpura
An IgA vasculitis
- presents with IgA antibody deposition in kidney
4 classic features: purpura (100%), joint pain (75%), abdominal pain (50%) and renal involvement (50%).
General tx for vasculitis
Corticosteroids
+ PPIs
+ Bisphosphonates
Define spondyloarthropathies
Assymetrical seronegative arthritis
Associated with HLAB27
An MHC-1 serotype - interacts with Tc (i.e. inflammatory)
General features of spondyloarthropathies
Remember SPINE ACHE
Sausage fingers (dactylitis)
Psoriasis
Iinflammatory back pain
NSAIDs have good response
Enthesitis (inflammation at site of tendon attachment)
Arthritis
Crohn’s / collitis
HLA B27
Eyes (Uveitis)
What are the types of spondyloarthropathies
Ankylosing spondylitis
Psoriatic arthritis
Reactive arthritis
Enteropathic arthritis
Juvenile idiopathic arthritis
Define Ankylosing spondylitis
Abnormal stiffening of pints (sacroiliac + vertebral) due to new bony formation…
Typical Px of Ankylosing spondylitis
Young male
HLA B27 +ve
Pathophysiology of Ankylosing spondylitis
Inflammation of the spine leads to erosive damage —> repair & new bone formation —> leads to irreversible fusion of spine —> reduced mobility of the spine
Syndesmophytes formation (vertical abnormal bony growths)
Signs and Sx of Ankylosing spondylitis
Back pain (stiffness in morning + at night)
Anterior uveitis
Enthesitis
Dactylitis
Decreased natural lumbar lordosis (more kyphosis)
Investigation and Dx of Ankylosing spondylitis
XRay: bamboo spine + sacroiliac (squared vertebral bodies)
MRI
Bloods: raised ESR + CRP
Genetic testing: HLA B27 +ve
Tx for Ankylosing spondylitis
NSAIDs
DMARDs - TNF-a blockers (Inflixamab)
Define psoriatic arthritis
10-40% with psoriasis develop within 10y
Sx of psoriatic arthritis
Moderate:
Inflamed distal interphalangeal joints (DIPJ)
+ nail dystrophy, dactylitis, enthesitis
Psoriatic rash on skin —> behind ears, scalp, under nails and penile
Severe:
Arthritis mutilans = pencil in cup deformity (osteolysis of bone, shortening fingers telescope in on themselves)
Tx for psoriatic arthritis
NSAIDs
DMARDS - methotrexate
If fails: TNF-a blocker - infliximab
If this fails: IL 12+23 inhibitor
Define reactive arthritis
Sterile inflammation of synovial membrane + tendon reacting to distant infection; usually GI or genitals
Types of gastroenteritis causing reactive arthritis
Salmonella
Shigella
Which sexual;LH transmitted organism can cause reactive arthritis
Chlamydia trachomatis
Sx of reactive arthritis
Reiter’s triad **Cant see, can’t pee, can’t climb a tree **
Uveitis, urethritis, arthritis
+ browny discolouration g rash on sides of foot
Main differential for reactive arthritis
Septic arthritis
Painful, hot, swollen and red joints + signs of infection Hx
Investigation and Dx for reactive arthritis
Joint aspirate (MC+S) and polarised light microscopy
- no organism
- negative for crystal arthropathies
HLAB27 +ve genetic testing
Tx for reactive arthritis
NSAIDs
DMARDS - methotrexate
± anti-TNFa (infliximab)
Types of infective arthritis
Septic arthritis
Osteomyelitis
What test is conducted for Ankylosing spondylitis
Do the schobers test
Measure 10 cm above and 5 cm below L5 if <20cm after bending forwards, then could be indicative of Ankylosing spondylitis
Define septic arthritis
Direct bacterial infection of the joint
Could have been either by direct exposure / haematogenous spread
Medical emergency; Acutely inflamed joint with a fever, typically of the knee.
Knee could be destroyed if not Tx ≤24hrs
Organisms that can cause septic arthritis
Staphylococcus aureus (most common)
H. Influenza (children; but now rare because of vaccination)
N. Gonorrhoea
Ecoli / pseudomonas (IVDU)
Risk factors for septic arthritis
IVDU
Immunosuppression
Trauma
Prosthetic joints; mainly infected by S.Epidermidis
Investigation and Dx of septic arthritis
URGENT JOINT ASPIRATION using MC+S & polarised light microscopy -
Septic arthritis: identified causative organism
Reactive arthritis: sterile, crystal-free
Gout: sterile, -ve birefringent Needle crystals
Pseudogout: sterile, +ve birefringent rhomboid crystals
Raised ESR + CRP in bloods
Tx for septic arthritis
Do joint aspiration drainage + empirical antibiotics:
Flucloxacillin (Gram -ve; ecoli / auriginosa / staph aureus.)
… OR …
Vancomycin (MRSA)
IM Ceftriaxone + Azithromycin (Gonorrhoea)
If on DMARDS (methotrexate), stop!!!
If on steroids, double dose (to increase the stress response)
NSAIDs for analgesia
Define osteomyelitis
Inflammation in a bone and bone marrow, usually caused by bacterial infection.
Spread of pathogen could have been haematogenous or direct contamination of the bones (during a fracture/surgery)
What type of organisms could cause osteomyelitis
Staph Aureus (90% - most common)
Salmonella in sickle cell Px
Risk factors for osteomyelitis
Immunosuppression
IVDU
Open fractures / trauma
Diabetes; especially diabetic foot ulceration
PVD
Pathophysiology of osteomyelitis
Osteomyelitis (OM) is an inflammatory condition affecting any bone in the skeleton, usually as a result of bacterial infection. Infection may occur due to haematogenous spread or result from direct penetration by a causative microorganism e.g. trauma. OM can be both acute or chronic in its presentation.
The most common organisms causing OM are:
Staphylococcus aureus: most common causative organism
Coagulase-negative staphylococcus
Streptococcus pneumonia: more common in children
Haemophilus influenzae: more common in unvaccinated children
Pseudomonas aeruginosa: increased risk with intravenous drug use
Salmonella species: most common cause in sickle-cell disease patients
Signs and Sx of osteomyelitis
Acute
Dull bony pain + hot swollen area (± joint ) —> worse with movement
Chronic
Above Sx + Deep ulceration - sequestrae (neotic bone embedded in pus)
Involucrum (Thick sclerotic bone placed around the sequestra to compensate for support)
Differential Dx for osteomyelitis
Charcot’s joint
Damage to sensory nerves due to diabetic neuropathy
Causes progressive degeneration of weight bearing joint + bony destruction. Affects the foot, presents with diabetic foot
Investigation and Dx of osteomyelitis
Bone marrow biopsy (MC+S):
Identify causative organism
Bloods: raised ESR and CRP
X-ray of affected area:
Osteopenia
Bone destruction
Periosteal reaction
Cortical breaches
Tx of osteomyelitis
Immobilise area+ antibiotics:
Flucloxacillin (aureus / salmonella)
Vancomycin (MRSA)
Teicoplannin is longer-lasting than vancomycin, but increased SE: GI upset/pruritus
Which antibiotic is longer lasting than vancomycin
Teicoplannin
Stronger Side effects:
GI upset
Pruritus
What needs to be ruled out in osteomyelitis using BM biopsy
Rule out TUBERCULOUS OSTEOMYELITIS
(+ve for caseating granuloma)
Define Paget’s disease
Focal disorder of bone remodelling (areas of patchy bone due to improper osteoblast/osteoclast function) — Areas of sclerosis + lysis
Signs and Sx of Paget’s disease
Bone pain
Bone deformity
Fractures
Hearing loss -
*Nerve compression of CN8
Hydrocephalus (Sylvian aqueduct) blockage *
Investigation and Dx of Paget’s disease
XRay:
Cotton-wool skull
Osteoporosis circumscripta
Urinary hydroxyproline —> protein constituents of bone collagen (marker for disease progression)
Tx for pagets
1st line:
Bisphosphonates
Aledronic / zoledronic acid
2nd line:
Calcitonin
Define fibromyalgia
MSK equivalent to IBS; Chronic widespread musculoskeletal pain for ≥ 3 months with all other causes ruled out
Risk factors for fibromyalgia
Females
Depression + stress
Poor
60+ y/o
Signs and Sx of fibromyalgia
Sleep disturbance
Morning stiffness
Esp. back and neck stiffness
Px: Stressed, depressed female 60+ and fatigue
Investigation and dx of fibromyalgia
No serological markers
No ESR or CRP raised
+ pain 11/18 regions palpated… clinical dx is made!
Tx for fibromyalgia
Educate Px + physiotherapy
Antidepressants for severe neuropathic pain (Amytryptyline; Tricyclic Antidepressant) + CBT
Differential dx of fibromyalgia
Polymyalgia rheumatica (PMR)
Large cell vasculitis presenting as chronic pain syndrome (affects muscles and joints) - similar to fibromyalgia
Dx of PMR:
Increased ESR + CRP (diagnostic)
Tx:
Oral prednisolone
