MSK Flashcards
What are the symptoms of osteoarthritis (OA)?
Joint pain that is exacerbated by exercise and relieved by rest
Joint stiffness in the morning or after rest (brief, rare)
Functional difficulties
Knee, hand, hip, or spine involvement
Bouchard’s nodes (PIP joints)
Heberden’s nodes (DIP joints)
Joint swelling/synovitis
Crepitus
What are the 1st line investigations for OA?
X-ray of affected joints (osteophytes, narrowing of joint spaces, subchondral sclerosis, cysts)
Normal CRP (exclude RA)
Normal ESR (exclude RA)
When do investigations not need to be considered for OA?
Patient is >45 years old, has activity-related joint pain, and has either no morning joint-related stiffness or has stiffness that lasts <30 minutes
What is the management plan for OA?
Topical NSAIDs and oral paracetamol (if not enough, oral NSAID and PPI)
Weight loss and exercise
Intra-articular corticosteroid injections
POTENTIAL JOINT REPLACEMENT THERAPY
What are the risk factors for OA?
Age >50 years
Female sex
Obesity
Family history
Physically demanding occupation/sport
Post-trauma/injury
What are the symptoms of SLE?
Photosensitive malar rash
Discoid rash
Raynaud’s phenomenon
Pericarditis/myocarditis
Fatigue, fever, mouth ulcers, lymphadenopathy
Arthralgia and non-erosive arthritis
Pleurisy
Proteinuria and glomerulonephritis
anxiety, depression, psychosis, seizures
What are the risk factors for SLE?
women
Afro-Caribbean
What are the first-line investigations for SLE?
Urinalysis (assess renal involvement)
FBC (normocytic anaemia of chronic disease, haemolytic anaemia)
APTT (prolonged in patients with antiphospholipid antibodies)
ANAs (less specific)
Anti-dsDNA antibodies, Smith antigen (more specific)
ESR and CRP (ESR elevated, CRP normal unless infection)
Complement (low C3 and C4)
How is SLE treated?
- Hydroxychloroquine
NSAID (naproxen)
Corticosteroid (prednisolone)
Immunosuppressant (methotrexate/azathioprine)
Belimumab/Rituximab (biologic)
What are the key diagnostic factors for rheumatoid arthritis (RA)?
Active symmetrical arthritis lasting >6 weeks
Joint pain and swelling (MCP, PIP, MTP)
Morning stiffness
Ulnar deviation
Rheumatoid nodules
Pleuritic chest pain (pleuritis/pericarditis)
Scleritis/uveitis
How is RA investigated?
Rheumatoid factor
Anti-CCP antibodies
X-ray (bony erosions, osteopenia, joint space narrowing)
Differentiate between radiographs of osteoarthritis and rheumatoid arthritis
Both have joint space narrowing (primary in OA, secondary to synovitis in RA)
OA has subchondral sclerosis and osteophytes
RA has bony erosions and osteopenia
How is RA treated?
Hydroxychloroquine or methotrexate (DMARD)
Consider corticosteroid (prednisolone)
Consider NSAID (ibuprofen or naproxen)
Consider biologic agent (infliximab, rituximab)
What are the key diagnostic factors for reactive arthritis?
Previous chlamydial or GI infection
Painful, swelling of joint (asymmetrical monoarthritis)
Spinal inflammation (non-specific lower back pain)
Fever, fatigue, weight loss
Enthesitis
Keratoderma blenorrhagia
Conjunctivitis, anterior uveitis
What are the risk factors for reactive arthritis?
Male sex
HLA-B27 genotype
Preceding chlamydial or GI infection
How is reactive arthritis treated?
analgesia, NSAIDs, intra-articular steroids
sulfasalazine and methotrexate for persistent disease
How is reactive arthritis investigated?
ESR and CRP (elevated)
ANA and Rheumatoid factor (negative)
X-ray (sacroiilitis, enthesitis)
Joint aspiration and gram staining to exclude septic arthritis
What are the key diagnostic factors for septic arthritis?
Hot, swollen, painful joint with restricted movement
Acute presentation
Fever
Large, single joint
Erythema migrans
How is septic arthritis investigated?
Joint aspiration and synovial fluid analysis (culture and sensitivities, microscopy, Gram stain, polarising microscopy)
ESR and CRP
How is septic arthritis treated?
Surgical lavage and IV antibiotics
Immobilise joint in acute phase
Physiotherapy once acute phase over
What are the key diagnostic factors for ankylosing spondylitis?
Inflammatory back pain >3 months
Early morning back stiffness, improvement with exercise
Enthesitis
Presentation in late teens/early 20s
Fatigue and sleep disturbance
Tenderness at sacroiliac joint
Dyspnoea
Loss of lumbar lordosis and kyphosis
What are the risk factors for ankylosing spondylitis?
HLA-B27 gene
Family history
Male sex
What are the investigations for ankylosing spondylitis?
X-ray (sacroiliitis, subchondral erosions, sclerosis, and squaring of lumbar vertebrae)
CXR (apical fibrosis)
Bamboo spine (late and unncommon)
MRI
What are the extra-articular manifestations of ankylosing spondylitis?
Iritis/uveitis
Psoriasis
Inflammatory bowel disease
What is the treatment for adults with ankylosing spondylitis?
NSAID
physiotherapy
sulphasalazine if peripheral joint involvement
What is osteomyelitis?
Infection in the bone and bone marrow, typically in the metaphysis of long bones
Infection may be introduced directly via open fracture or through the blood
What are the risk factors for osteomyelitis?
More common in boys and children <10 years
Open bone fracture
Orthopaedic surgery
Immunocompromised
Sickle cell anaemia
HIV
Tuberculosis
What are the symptoms of osteomyelitis?
Pain
Fever
Swelling and erythema
Refusal to use limb or weight bear
How is osteomyelitis investigated?
MRI (best imaging for establishing diagnosis)
X-ray (can be normal)
ESR and CRP (raised)
FBC (raised WCC)
Blood culture (establish causative organism)
What is the most common causative organism for osteomyelitis?
Staphylococcus aureus
In patients with sickle cell, Salmonella species dominate
IV drug users are also predisposed to pseudomonas aeruginosa
How is osteomyelitis treated?
Flucloxacillin for 6 weeks
Clarithromycin if allergic
May require surgery for drainage and debridement of the infected bone
What is gout and pseudogout?
Gout is the deposition of urate crystals
Pseudogout is the deposition of calcium pyrophosphate crystals
What are the symptoms of gout?
Commonly affects 1st MTP joint
Pain, swelling, tenderness, stiffness
How is gout investigated?
Synovial fluid analysis (needle shaped negatively birefringent monosodium urate crystals)
Urate (high)
X-ray (joint effusions, ‘rat bite’ erosions, soft tissue tophi)
How is gout managed?
NSAIDs or colchicine
Prednisolone if NSAIDs/colchicine are contraindicated
Intra-articular steroid injection?
Allopurinol as urate-lowering therapy
What are the risk factors for pseudogout?
Increasing age
Haemochromatosis
Hyperparathyroidism
Low magnesium, low phosphate
Acromegaly
Wilson’s disease
How is pseudogout investigated?
Knee, wrist and shoulders commonly affected
Joint aspiration: positively birefringent rhomboid-shaped crystals
X-ray (chondrocalcinosis)
How is pseudogout investigated?
Knee, wrist and shoulders commonly affected
Joint aspiration: positively birefringent rhomboid-shaped crystals
X-ray (chondrocalcinosis - thin white line in the middle of the joint space)
What are the risk factors for gout?
Male
Obesity
High purine diet (e.g. meat and seafood)
Alcohol
Diuretics
FHx
What is osteomalacia?
Defective bone mineralisation, due to insufficient vitamin D levels
What are the causes of osteomalacia?
Vitamin D deficiency (malabsorption, lack of sunlight, diet)
CKD
Drug-induced, e.g. anticonvulsants
Coeliac disease
Liver disease, e.g. cirrhosis
What are the features of osteomalacia?
bone pain
bone/muscle tenderness
pathological fractures: especially femoral neck
proximal myopathy: may lead to a waddling gait
How is osteomalacia investigated?
FBC and bony profile (low vitamin D, low calcium, raised ALP)
X-ray (looser zones, pseudofractures, osteopenia)
DEXA (low bone mineral density)
How is osteomalacia treated?
Supplementary vitamin D (cholecalciferol) - loading dose often initially needed
Calcium supplementation if dietary calcium is inadequate
What is osteoporosis?
Presence of bone mineral density of less than 2.5 SDs below the young adult mean density
What are the risk factors for osteoporosis?
Increasing age
Female sex
Long-term corticosteroid use
Smoking
Alcohol
Low BMI
FHx
How is fracture risk assessed?
FRAX score estimates the 10-year risk of fragility fracture
Low risk – reassure
Intermediate risk – offer DEXA scan and recalculate the risk with the results
High risk – offer treatment
How is osteoporosis managed?
Vitamin D and calcium supplementation
Alendronate (bisphosphonate)
Strontium ranelate and raloxifene if bisphosphonates not tolerated
What are the side effects of bisphosphonates?
Reflux and oesophageal erosions - bisphosphonates taken on an empty stomach to prevent this
Atypical fractures (e.g. atypical femoral fractures)
Osteonecrosis of the jaw
Osteonecrosis of the external auditory canal
What is polymyalgia rheumatica?
Inflammatory condition that causes pain and stiffness in the shoulders, pelvic girdle and neck - strong association with giant cell arteritis
What are the risk factors for polymyalgia rheumatica?
> 50 years
Female
Caucasian
What are the features of polymyalgia rheumatica?
rapid onset (<1 month)
bilateral shoulder pain that may radiate to the elbow, pelvic girdle pain
worse with movement and interferes with sleep
morning stiffness
weight loss, fatigue, low grade fever and low mood
upper arm tenderness
carpel tunnel syndrome
pitting oedema
How is polymyalgia rheumatica investigated?
ESR and CRP (usually raised)
Creatine kinase and EMG are normal
How is polymyalgia rheumatica treated?
15mg prednisolone OD - if no symptom improvement after 1 week, consider alternative diagnosis
What are the features of dermatomyositis?
Muscle pain, fatigue and weakness - bilateral
Affects shoulder and pelvic girdle
Gottron papules on knuckles, elbows and knees
Photosensitive erythematous rash
Perioribital oedema
How is dermatomyositis investigated?
Malignancy screen (lung, breast, ovarian, gastric)
Creatinine kinase levels (raised)
ANAs, anti-Jo-1, anti-Mi-2
EMG
Muscle biopsy
How is dermatomyositis treated?
High-dose corticosteroids - CK is monitored to taper the dose
Methotrexate or azathioprine
IV immunoglobulins
