MSK Flashcards
What are degenerative MSK disorders?
Disorders involving progressive impairment of both the structure and function of part of the body e.g. osteoarthritis
What are inflammatory MSK disorders?
Disorders involving a local response to cellular injury that is marked by redness, heat, pain, swelling and often loss of function e.g. rheumatoid arthritis
What are seronegative/seropositive MSK disorders testing for?
Rheumatoid factor
Name 2 differences between inflammatory and degenerative disorders
Inflammatory pain eases with use, degenerative pain increases with use
Inflammatory is significantly stiff for >60mins in the morning, degenerative is not prolonged <30mins
What are the 4 pillars of inflammation?
Red (rubor), painful (dolor), hot (calor), swollen (tumour)
What are the 2 markers of inflammation?
ESR and CRP
What is osteoarthritis?
A group of diseases characterised by joint degeneration. It is an age-related, dynamic reaction pattern of a joint in response to insult or injury
What are the features of osteoarthritis?
Affects synovial joints
All tissues of the joint are involved
Articular cartilage is the most affected
Describe the pathology of osteoarthritis
Insult to joint tissue initiating a cycle of cellular events, including low-grade chronic inflammation of the synovium, release of metalloproteinases, and degradation of articular cartilage matrix
What are the main pathological features of osteoarthritis?
Loss of cartilage, disordered bone repair
What are the risk factors for osteoarthritis?
Age, female gender, genetic predisposition, obesity, occupation
How does osteoarthritis present?
Joint pain, tenderness, swelling of small joints, stiffness, symptoms typically worsen during the day with activity
How is osteoarthritis diagnosed?
Radiographs show LOSS; Loss of joint space Osteophytes Subarticular sclerosis Subchondral cysts
How is osteoarthritis managed?
Activity and exercise, weight loss
Analgesia, NSAIDs, DMARDs
Joint replacement/ arthroplasty
What is rheumatoid arthritis?
A multisystem autoimmune disease in which the brunt of disease activity falls upon the synovial joints
How does rheumatoid arthritis present?
Symmetrical, swollen, painful, stiff, small joints of hands and feet
Symptoms typically worse in morning
Where are rheumatoid nodules commonly found?
Pressure points e.g. olecranon
How is rheumatoid arthritis diagnosed?
Rheumatoid factor is positive
X-rays show soft tissue swelling, juxta-articular osteopenia and decrease joint space
US and MRI can identify synovitis
How is rheumatoid arthritis managed?
DMARDs
Steroids reduce symptoms and inflammation
Surgery may relieve pain, improve function, prevent deformity
What are the different patterns of fractures?
Transverse, oblique, spiral, butterfly, comminution, segmental, greenstick
How are fractures managed?
Analgesia, reduce, immobilise, rehabilitate
What are the risk factors for fractures?
Osteoporosis, metabolic bone disease e.g. osteomalacia, Paget’s disease, bone infiltrated by malignant tumours
Briefly describe how fractures heal
Haematoma organised and dead bone removed, callus formed, then replaced by trabecular bone, and finally remodelled into lamellar bone
Fracture healing delayed if bone ends are mobile, infected very badly, misaligned or avascular
What is osteoporosis?
A metabolic bone disease characterised by a generalised reduction in bone mass, increased bone fragility, and predisposition to fracture
What is the primary cause of osteoporosis?
Post-menopausal and age related (70+)
What are the secondary causes of osteoporosis?
Cushing’s, hyperparathyroidism, hypogonadism, coeliac disease, IBD, poor nutrition
What are the risk factors for osteoporosis?
SHATTERED;
Steroid use, hyperthyroidism, alcohol, thin, testosterone low, early menopause, renal failure, erosive bone disease, dietary low calcium
Why are women more likely to develop osteoporosis after menopause?
Oestrogen deficiency accelerates bone loss
What increases bone loss with increasing age?
Decreased bone turnover, decreased physical activity, reduce sex hormones and reduced calcium absorption from the gut
How can post-menopausal osteoporosis be prevented?
Oestrogen replacement
What changes to trabecular architecture occur with osteoporosis due to ageing?
Decreases in trabecular thickness, more pronounced for non-load bearing horizontal trabeculae
Decrease in connections between horizontal trabeculae
Decrease in trabecular strength and increased susceptibility to fracture
How does osteoporosis present?
Usually clinically silent until fragility fractures occur
What fractures are common when trabecular bone is affected?
Crush fractures of vertebrae
What fractures are common when cortical bone is affected?
Long bone fractures e.g. femoral neck
How is osteoporosis diagnosed?
X-ray: after a fracture
Bone densitometry DEXA scan: T score is number of standard deviations the bone mineral density is from the youthful average
What T score is osteopenia?
-1 to -2.5
What T score is osteoporosis?
-2.5 or worse
What questionnaire is used to evaluate the fracture risk of patients?
FRAX questionnaire - gives a 10 year probability of a fracture
How is osteoporosis managed through lifestyle measures?
Quit smoking and reduce alcohol consumption
Weight-bearing exercise may increase bone mineral density
Balance exercises such as tai chi reduce risk of falls
Calcium and vitamin D rich diet
How is osteoporosis managed pharmacologically?
1st line - bisphosphonates e.g. alendronic acid - decreases osteoclast activity and bone turnover
HRT - post-menopausal women
What is systemic sclerosis?
Condition featuring scleroderma (skin fibrosis), internal organ fibrosis and microvascular abnormalities
What are the features of systemic sclerosis?
Skin disease is limited (involves face/hands/feet) or diffuse (whole body).
No cure, immunosuppression required with BP monitoring
What are polymyositis and dermatomyositis?
Rare conditions characterised by insidious onset of progressive symmetrical proximal muscle weakness and autoimmune-mediated striated muscle inflammation
What is systemic lupus erythematosus?
A multisystem autoimmune disease characterised by autoantibody production against a number of nuclear and cytoplasmic autoantigens
Describe the pathology of SLE
Circulating immune complexes become deposited in tissues such as the skin, joints and kidneys where they stimulate inflammation and tissue damage
How does SLE present?
Fatigue, weight loss, low-grade fever, arthralgia (joint involvement), scaly red lesions on sun-exposed sites (skin involvement)
How is SLE diagnosed?
Clinical criteria
Acute - Malar rash
Chronic - Discoid rash
Synovitis, serositis, presence of proteinuria, thrombocytopenia
How is SLE managed?
Prednisolone for flares
NSAIDs, advance to methotrexate for maintenance
High-factor sun cream
What is Sjogren’s syndrome?
A chronic inflammatory autoimmune disorder, which may be primary or secondary, associated with connective tissue disease
What can Sjogren’s syndrome be secondary to?
SLE, rheumatoid arthritis, scleroderma, primary biliary cirrhosis
What are the features of Sjogren’s syndrome?
Decreased tear production, decreased salivation, parotid swelling, systemic signs such as Raynaud’s phenomenon
How is Sjogren’s syndrome diagnosed?
Schirmer’s test to measure conjunctival dryness
Rose Bengal stain may show keratitis
Biopsy shows focal lymphocytic aggregation
How is Sjogren’s syndrome managed?
Treat symptoms e.g. hypromellose (artificial tears), frequent drinks
NSAIDs for arthralgia
What is Raynaud’s phenomenon?
Peripheral digital ischaemia due to paroxysmal vasospasm, precipitated by cold or emotion
What do the colours of the fingers/toes in Raynaud’s indicate?
Pale -> ischaemia
Blue -> deoxygenation
Red -> reactive hyperaemia
How is Raynaud’s phenomenon managed?
Keep warm e.g. hand warmers
Stop smoking
Chemical or surgical (lumbar or digital) sympathectomy may help in those with severe disease
What are seronegative spondyloarthropathies?
A group of inflammatory joint diseases characterised by arthritis affecting the spinal column and peripheral joints, and enthesitis
What does seronegative mean?
Rheumatoid factor is negative
What are the shared clinical features of the spondyloarthropathies?
Seronegativity, HLA B27 association, axial arthritis, enthesitis, dactylitis
What is ankylosing spondylitis?
A chronic inflammatory disease of the spine and sacroiliac joints
How does ankylosing spondylitis present?
Lower back pain, typical case worse during the night with morning stiffness relieved by exercise.
Extra-articular manifestations - iritis, pulmonary fibrosis, aortitis
How is ankylosing spondylitis diagnosed?
Clinical - supported by imaging
MRI shows active inflammation
X-rays can show joint space narrowing
What are the patterns of psoriatic arthritis?
Symmetrical polyarthritis, DIP joints, asymmetrical oligoarthritis, spinal
How does psoriatic arthritis present?
Affects the interphalangeal joints and may lead to severe deformation
How is psoriatic arthritis diagnosed?
Radiology: erosive changes
Nail changes, synovitis, acneiform rashes
How is psoriatic arthritis managed?
NSAIDs (methotrexate)
Anti-TNF agents
What is reactive arthritis?
A condition in which arthritis and other clinical manifestations occur as an autoimmune response to infection elsewhere in the body
What infections are related to reactive arthritis?
Chlamydia, shigella, salmonella, campylobacter
How does reactive arthritis present?
Pain and stiffness in the lower back, knees, ankles and feet
Enthesitis.
Triad: urethritis, arthritis, conjunctivitis
What is enthesitis?
Inflammation at the insertion site of tendons and ligament to bone
How is reactive arthritis diagnosed?
Increased ESR and CRP, culture stool if diarrhoea, infectious serology
X-ray may show enthesitis
How is reactive arthritis managed?
No cure. Splint affected joints - treat with NSAIDs or local steroid injections.
Methotrexate if >6 months
What are crystal arthropathies?
A group of joints diseases caused by deposition of crystals in joints
Describe the pathology of crystal arthropathies
Crystals are deposited in joints, neutrophils ingest the crystals and degranulate, releasing enzymes that damage the joint
What causes gout?
Deposition of monosodium urate crystals in joint
How does gout present?
Acute, painful, swollen, red joint - typically first metatarsophalangeal joint
What is chronic tophaceous gout?
Large deposits of urate occur in the skin and around joints
What are the risk factors for gout?
Reduced urate excretion (impaired renal function, hypertension, elderly)
Excess urate production (dietary, genetic disorders, psoriasis)
How is gout diagnosed?
Polarised light microscopy of synovial fluid shows negatively birefringent urate crystals
Serum urate raised
How is gout managed?
High-dose NSAID
Rest and elevate joint.
How is gout prevented?
Lose weight, avoid prolonged fasts, alcohol excess, low-dose aspirin
What is pseudogout?
Calcium pyrophosphate deposition
What causes pseudogout?
Deposition of calcium pyrophosphate crystals in a joint
How does pseudogout present?
Acute gout attack, pain in knee/wrist, low-grade fever, stiffness, swelling
What is an acute gout attack?
Crystals break loose from their locations and move into a joint space. This causes sudden pain in the joint along with redness, warmth and inflammation
How is pseudogout diagnosed?
Polarised light microscopy of synovial fluid shows weakly urate positive birefringent crystals.
X-ray: soft tissue calcium deposition
How is psuedogout managed?
Acute attacks: cool packs, rest, aspiration
NSAIDs may prevent acute attacks
What is vasculitis?
A group of conditions in which inflammation and damage to blood vessels is the primary underlying pathology
Name an example of a small, medium and large vessel vasculitis
Large - Giant cell arteritis
Medium - Polyarteritis nodosa
Small - Goodpasture’s disease
What are the features of vasculitis?
Fever, malaise, weight loss, purpura, ulcers, angina, pericarditis, malabsorption, hypertension
How is vasculitis managed?
Large-vessel: steroids
Medium/small: immunosuppression - steroids
What is giant cell arteritis?
A vasculitis of medium and large vessels which preferentially affects head and neck arteries.
How does giant cell arteritis present?
Fever, anorexia, weight loss
Temporal artery - headache, scalp tenderness, jaw claudication
Occular vessels - blindness
How is giant cell arteritis diagnosed?
Positive temporal artery biopsies show lymphohistiocytic infiltrate
Raised ESR and CRP
How is giant cell arteritis managed?
Start prednisolone PO immediately or IV methylprednisolone if evolving visual loss
What is the prefix for bone tumours?
Osteo
What is the prefix for cartilage tumours?
Chondro
What is the prefix for skeletal muscle tumours?
Rhabdomyo
What is the prefix for fat tumours?
Lipo
What does the suffix ‘Oma’ tell us?
Benign tumour
What is a sarcoma?
Malignant connective tissue tumour
What is a carcinoma?
Malignant epithelial/ endothelial tumour
What is a blastoma?
Malignant tumour of embryonic cells
What are secondary bone tumours?
Tumours that have metastasised to bone
How are most MSK tumours managed?
Chemo/radiotherapy
Surgery
Local recurrence increases risk of amputation
What is an osteochondroma?
Benign cartilaginous-forming tumour of bone
What are osteoid osteomas?
Benign bone-forming tumours of bone - long bones
What are osteoblastomas?
Benign bone-forming tumours of bone - axial skeleton
What are endochondromas?
Benign cartilaginous-forming tumour of bone that occur in small bones
What are the 5 most common tumours to metastasise to bone?
Lung, breast, kidney, thyroid, prostate
What are osteosarcomas?
Malignant bone-forming tumours
What are giant cell tumours?
Benign, locally aggressive neoplasms of bone that arise in the ends of long bones
What is Ewing’s sarcoma?
A malignant round cell tumour of bone of neuroectodermal origin (neural crest cells)
What is fibromyalgia?
A long term condition that causes pain all over the body. Very similar to chronic fatigue syndrome
What are the risk factors for fibromyalgia?
Female, middle age, low household income, divorced, low educational status
How does fibromyalgia present?
Allodynia, hyperaesthesia, profound fatigue, complaint of unrefreshing sleep, morning stiffness, headaches, poor concentration
How is fibromyalgia diagnosed?
Diagnosis is clinical
How is fibromyalgia managed?
Encourage patient to stay active and continue with work
Cognitive behavioural therapy
Pharmacotherapy - low-dose amitriptyline relieves pain and improves sleep
What are the red flags of back pain?
Constant/ progressive pain Nocturnal pain Fever, night sweats, weight loss Abdominal mass Morning stiffness Neurological disturbance
What are the most common causes of back pain in 15-30 year olds?
Prolapsed disc, trauma, fractures, ankylosing spondylitis, pregnancy
How is mechanical back pain investigated?
MRI - can detect disc prolapse, cord compression, cancer, infection or inflammation
X-ray - fractures/abnormalities
How is mechanical back pain managed?
Low-dose amitriptyline
Physiotherapy, acupuncture, exercise programme
Education and active
Urgent neurosurgical referral if any neurological deficit
What is septic arthritis?
Infection within a joint
What are the risk factors for septic arthritis?
Pre-existing joint disease, diabetes mellitus, immunosuppression, CKD, recent joint surgery
How does septic arthritis present?
Extremely painful, hot, red, swollen joint
Fever
Knee > hip > shoulder
How is septic arthritis diagnosed?
Microbiology: Staphylococcus aureus/
Urgent joint aspiration for fluid microscopy - no crystals
Culture for causative organism
How is septic arthritis managed?
Empirical IV antibiotics (after aspiration - until sensitivities known)
Flucloxacillin
Analgesia
Ceftriaxone for gonococcus
What are common causative organisms of septic arthritis?
Staph. aureus, streptococci, Neisseria gonococcus, and gram -ve bacilli
What is osteomyelitis?
Infection of a bone
How can infection occur in a bone?
Haematogenous spread
Penetrating trauma e.g. open fracture
Iatrogenic e.g. following joint replacement
Direct spread from an adjacent infection e.g. complication of a diabetic foot ulcer
Describe the pathology of osteomyelitis
Infection leads to influx of acute inflammatory cells into bone
Destruction of bone leads to necrotic bone (sequestrum)
How does osteomyelitis present?
Fever and pain in the affected bone
Aggravated by movement
Tenderness, warmth, erythema, swelling
How is osteomyelitis diagnosed?
Microbiology - most caused by staphylococcus aureus
Bloods: high WCC
Raised inflammatory markers
How is osteomyelitis managed?
IV antibiotics and surgical debridement of any necrotic bone
What is osteomalacia?
A metabolic bone disease characterised by inadequate mineralisation of bone in the mature skeleton
What is rickets?
A metabolic bone disease characterised by inadequate mineralisation of bone and epiphyseal cartilage in the growing skeleton of children
Describe the pathology of osteomalacia and rickets
There is inadequate mineralisation of bone matrix (osteoid) due to lack of calcium and occasionally phosphate
Bone becomes soft and prone to deformity and fracture
How does osteomalacia present?
Bone pain and tenderness, fractures, proximal myopathy
How are rickets and osteomalacia diagnosed?
Bone biopsies: incomplete mineralisation
X-ray: loss of cortical bone
Plasma: mildly reduced calcium
How are rickets and osteomalacia managed?
Vitamin D supplementation results in rapid mineralisation of bone and resolution of symptoms
Renal disease - alfacalcidol
What is Paget’s disease?
A metabolic bone disease characterised by excessive chaotic bone turnover in localised parts of the skeleton
How does Paget’s disease present?
Asymptomatic - diagnosis made incidentally on radiology
Symptomatic disease usually presents with bony pain and deformity
How is Paget’s disease diagnosed?
X-ray: localised enlargement of bone. Patchy cortical thickening with sclerosis, osteolysis and deformity
How is Paget’s disease managed?
Bisphosphonates - block osteoclasts from resorbing bone
Analgesia for pain
When is capsaicin used?
Symptomatic relief in osteoarthritis
What are the side effects of capsaicin?
Cough, sneezing, watering eye, asthma exacerbated
When is paracetamol used?
For mild to moderate pain
What are the side effects of paracetamol?
Thrombocytopenia, bronchospasm, rash, hepatic function abnormal
When are NSAIDs used?
Rheumatoid/ osteoarthritis
Give an example of an NSAID
Diclofenac, aceclofenac
What are the side effects of NSAIDs?
Diarrhoea, dizziness, GI discomfort/ nausea
Give an example of a bisphosphonate
Alendronic acid
How do bisphosphonates work?
Bisphosphonates are adsorbed onto hydroxyapatite crystals in bone, slowing both their rate of growth and dissolution, and therefore reducing the rate of bone turnover
What are the side effects of bisphosphonates?
Alopecia, anaemia, constipation, diarrhoea, headache, fever, malaise
What does DMARD stand for?
Disease-modifying antirheumatic drugs
Give an example of a DMARD
Methotrexate, hydroxychloroquine
How does methotrexate work?
Methotrexate inhibits the enzyme dihydrofolate reductase, essential for the synthesis of purines and pyrimidines
When is methotrexate used?
Used to treat moderate to severe active rheumatoid arthritis by mouth, and severe RA by IM/SC injection
What are the side effects of methotrexate?
Fever, headache, nausea, vomiting, anemia, diarrhoea, fatigue, drowsiness
When is hydroxychloroquine used?
Active rheumatoid arthritis
What are the side effects of hydroxychloroquine?
Abdominal pain, diarrhoea, vomiting, vision disorders, headache
