Musculoskeletal Flashcards
Define amyloidosis.
Heterogenous group of diseases characterised by extracellular deposition of amyloid fibrils.
- Type AA = serum amyloid A protein*
- -Type AL = Monoclonal immunoglobulin light chains*
- Type ATTR (familial amyloid polyneuropathy) = Genetic-variant transthyretin*
What are the presenting signs and symptoms of amyloidosis?
o Renal = proteinuria, nephrotic syndrome, renal failure
o Cardiac = restrictive cardiomyopathy, heart failure, arrhythmia, angina
o GI = macroglossia (characteristic of AL), hepatosplenomegaly, gut dysmotility, malabsorption, bleeding
o Neurological = sensory and motor neuropathy, autonomic neuropathy, carpal tunnel syndrome
o Skin = waxy skin and easy bruising, purpura around the eyes (characteristic of AL), plaques and nodules
o Joints = painful asymmetrical large joints, enlargement of anterior shoulder
o Haematological = bleeding tendency
What are the appropriate investigations for amyloidosis?
o Tissue Biopsy
o Urine = proteinuria, free immunoglobulin light chains (in AL)
o Bloods = CRP/ESR, Rheumatoid factor, Immunoglobulin levels, Serum protein electrophoresis, LFTs, U&Es
o SAP Scan = radiolabelled SAP will localise the deposits of amyloid
Define ankylosing spondylitis.
Seronegative inflammatory arthropathy affecting preferentially the axial skeletal and large proximal joints.
What are the risk factors/causes of ankylosing spondylitis?
o Unknown cause
- Linked to HLA-B27 (over 90% of cases)
- Possible infective triggers and antigen cross-reactivity
What are the presenting symptoms of ankylosing spondylitis?
o Lower back and sacroiliac pain
o Disturbed sleep
o Pain pattern -> worse in the morning or with rest but better with activity
o Progressive loss of spinal movement
o Symptoms of asymmetrical peripheral arthritis
o Pleuritic chest pain (due to costovertebral joint involvement)
o Heel pain (due to plantar fasciitis)
o Non-specific symptoms (e.g. malaise, fatigue)
What are the clinical signs of ankylosing spondylitis on examination?
o Reduced range of spinal movement (particularly hip rotation)
o Reduced lateral spinal flexion
o Schober’s Test = 2 fingers are placed on the patients back about 10 cm apart -> patient is asked to bend over -> distance between the two fingers should increase by > 5 cm on forward flexion -> reduced movement would suggest ankylosing spondylitis
o Tenderness over the sacroiliac joints
o Later stages = Thoracic kyphosis, Spinal fusion, Question mark posture
o Signs of Extra-Articular Disease = 5 As = Anterior uveitis, Apical lung fibrosis, Achilles tendinitis, Amyloidosis, Aortic regurgitation
What are the appropriate investigations for ankylosing spondylitis?
o Bloods = FBC (anaemia of chronic disease, Rheumatoid factor (negative), ESR/CRP (high)
o Radiographs
- Anteroposterior and lateral radiographs of the spine = Bamboo spine
- Anteroposterior radiograph of sacroiliac joints = Symmetrical blurring of joint margins
- Later stages = erosions, sclerosis, sacroiliac joint fusion
- CXR = check for apical lung fibrosis
o Lung Function Tests = assess mechanical ventilatory impairment due to kyphosis
Define spondylosis.
Progressive degenerative process affecting the vertebral bodies and intervertebral discs, and causing compression of the spinal cord and/or nerve roots.
What are the presenting symptoms of spondylosis?
o Neck/Back pain/stiffness
o Arm pain (stabbing or dull ache)
o Paraesthesia
o Weakness
o Clumsiness in the hands
o Weak and stiff legs
o Gait disturbance
o Atypical chest pain
o Breast pain
o Pain in the face
What are the clinical signs of spondylosis on examination?
o Arms = atrophy of the forearm and hand muscles, segmental muscle weakness in a nerve root distribution, hyporeflexia, sensory loss (mainly pain and temperature), pseudoathetosis (writhing finger movements when hands are outstretched, fingers spread and eyes closed)
o Legs = increased tone, weakness, hyper-reflexia, extensor plantar response, reduced vibration and joint position sense
o Lhermitte’s Sign = neck flexion causes crepitus (grating sound) and/or paraesthesia down the spine
What are the appropriate investigations for spondylitis?
o Spinal X-ray - lateral
Define gout.
A disorder of uric acid metabolism causing recurrent bouts of acute arthritis caused by deposition of monosodium urate crystals in joints, soft tissues and kidneys.
What are the causes of gout?
o Hyperuricaemia
- Increased urate intake or production = increased dietary intake, increased nucleic acid turnover (e.g. lymphoma, leukaemia, psoriasis), increased synthesis of urate (e.g. Lesch-Nyhan syndrome)
- Decreased Renal Excretion = idiopathic, drugs (e.g. ciclosporin, alcohol, loop diuretics), renal dysfunction
What are the presenting signs and symptoms of an acute attack of gout?
o Precipitating factors = trauma, infection, alcohol, starvation, introduction or withdrawal of hypouricaemic agents
o Sudden excruciating monoarticular pain - usually affects the metatarsophalangeal joint of the great toe with symptoms peaking at 24 hrs
They resolve over 7-10 days
o Can present with cellulitis, polyarticular or periarticular involvement
What are the presenting signs and symptoms of intercritical gout?
o None
- Intercritical gout = asymptomatic period between acute attacks
What are the presenting signs and symptoms of chronic tophaceous gout?
o Follow repeated acute attacks
o Persistent low-grade fever
o Polyarticular pain with painful tophi (urate deposits)
o Best seen on tendons and the pinna of the ear
What are the presenting signs and symptoms of urate urolithiasis?
o Renal calculi symptoms
- Severe pain in the groin and/or side
- Blood in urine
- Vomiting and nausea
- WBCs or pus in the urine
- Reduced amount of urine excreted
- Burning sensation during urination
- Persistent urge to urinate
- Fever and chills if there is an infection
What are the appropriate investigations for gout?
o Synovial Fluid Aspirate = monosodium urate crystals will be seen - needle-shaped, negative birefringence under polarised light microscopy
- Microscopy and culture will also be performed to exclude septic arthritis
o Bloods = FBC (raised WCC), U&Es, Raised urate, Raised ESR
o AXR/KUB Film = Uric acid renal stones may be seen
Define pseudogout.
Arthritis associated with deposition of calcium pyrophosphate dihydrate (CPPD) crystals in the joint cartilage.
What are the risk factors for pseudogout?
o Joint damage - osteoarthritis, trauma etc
o Precipitating factors = Intercurrent illness, Surgery, Local trauma
o Rarer conditions = Haemochromatosis, Hyperparathyroidism, Hypomagnesaemia, Hypophosphatasia
What are the presenting symptoms of pseudogout?
o Acute Arthritis = Painful, Swollen Joint
o Chronic Arthropathy = Pain, Stiffness, Functional impairment
o Uncommon Presentations = Tendonitis, Tenosynovitis, Bursitis
What are the clinical signs of pseudogout on examination?
o Acute Arthritis = Red, Hot, Tender, Restricted range of movement, Fever
o Chronic Arthropathy = Similar to osteoarthritis, Bony swelling, Crepitus, Deformity, Restriction of movement
What are the appropriate investigations for pseudogout?
o Bloods = High WCC in acute attacks, High ESR
o Blood culture = exclude septic arthritis
o Joint Aspiration = Rhomboid, brick-shaped crystals, positive birefringence, culture/gram-staining to exclude septic arthritis
o Plain Radiograph of the Joint = Chondrocalcinosis
- Signs of osteoarthritis = Loss of joint space, Osteophytes, Subchondral cysts, Sclerosis