Musculoskeletal conditions Flashcards
What is Ankylosing Spondylitis?
Chronic, seronegative, inflammatory arthropathy.
Patients present with severe pain and spinal stiffness. It primarily involves the axial skeleton. Involves the whole spine but mostly the sacro-illiac joint.
What is the cause of ankylosing spondylitis?
97% heterability
HLA-B27
Infective triggers and antigen-cross reactivity with self-peptides hypothesised
Mainly affects spine and sacroiliac joint
What is the pathophysiology of ankylosing spondylitis?
Inflammation at start of entheses
Persistent inflammation leads to reactive new bone formation
Changes begin in lumbar vertebrae and progress superiorly
Syndesmophytes (vertial ossifications bridging margins between adjacent vertebrae)
Fusion of syndesmophytes and facet joints
Calcificaiton of anterior and lateral spinal ligaments
What are Risk factors for Ankylosing spondylitis?
HLA-B27
Endoplasmic reticulum aminopeptide 1 and IL-23 receptor genes
Family history
Klebsiella Pneumoniae
What are the symptoms of Ankylosing spondylitis?
Inflammatory back pain Iritis/Uveitis Lower back and sacroiliac pain Pain pattern (worse in morning, better with activity, worse when resting) Progressive loss of spinal movement Assymetrical peripheral arthritis Pleuritic chest pain Head pain Non-specific symptoms Blindness due to acute iritis in 1/3
What are the signs of Ankylosing spondylitis?
Reduced range of spinal movement
Reduced lateral spine flexion
Schober’s test (fingers move on patient’s back)
Tenderness over sacroiliac joints
Later: Thoracic kyphosis, spinal fusion
What are signs of extra articular disease for Ankylosing spondylitis?
Anterior uveitis Apical lung fibrosis Achilles tendinitis Amyloidosis Aortic regurgitation
What investigations are done for Ankylosing spondylitis?
FBC (anaemia of chronic disease) Rheumatoid factor (Negative) ESR (High) CRP (High) HLA B27 (Positive but not diagnostic)
Radiograph (MRI best)
What is seen on imaging of ankylosing spondylitis?
Anteroposterior and lateral radiographs:
- Vertical syndesmophytes
- Bony proliferation due to enthesitis between ligaments and vertebrae
Anteroposterior radiographs of sacroiliac joints:
- show symmetrical blurring of joint margins
Later stages: Erosions, sclerosis, sacroiliac joint fusion
Lung function test: Assessmechanical ventilatory impairment due to kyphosis
What is carpal tunnel syndrome?
Symptoms arising from copression of the median nerve in the carpal tunnel
What causes carpal tunnel syndrome?
Idiopathic but if secondary than multifactiorial
What are the secondary causes?
MEDIAN TRAPS M - Myxoedema E - Enforced flexion D - Diabetic Neuropathy I - Idiopathic A - Acromegaly N - Neoplasms T - Tumours (benign) R - Rheumatoid arthritis A - Amyloidosis P - Pregnancy S - Sarcoidosis
What are the Risk Factors for Carpal tunnel syndrome?
30+ High BMI Female Fractures wrist/carpal bones Square wrist Rheumatoid arthritis Diabetes Dialysis Pregnancy Congenital carpal tunnel stenosis Occupation involving exposure to repetitive bending Mobility aids Smoking ciggarettes White Thyroid disorders HRT Physical inactivity
What are the symptoms of carpal tunnel syndrome?
Paraesthesia in hands/fingers
Weakness
Clumsiness
What are the signs of Carpal tunnel syndrome?
Sensory impairment in median nerve distribution
Weakness and wasting of thenar eminance
Tinel’s sign (tapping carpal tunnel causes tingling in nerve distribution)
Phalen’s test (flexion for 1 min causes tingling)
Signs of underlying (acromegaly, hypothyroidism)
What investigations are done for Carpal tunnel syndrome?
Clinical diagnosis
- EMG (Slowing of conduciton)
- US/MRI of wrist (Rarely done)
What is 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 is the cause of gout?
Main metabolic disturbance is hyperuricaemia
Monosodium urate crystals deposit in joints leading to inflammation an dpain
May be caused by:
Increased urate intake or production
- Increased dietary intake of purines - shellfish
- Increased nucleic acid turonover
- Increased synthesis of urate (e.g. Lesch-Nylan syndrome)
Decreased renal function
- Idiopathic
- Dehydration
- Drugs (e.g ciclosporin)
- Renal dysfunction
What are the risk factors for Gout?
Older age Male sex Menopausal status Consumption of meat, seafood and alcohol Use of diuretics Use of ciclosporin or tacrolimus Use of pyrazinamide Use of aspirin Genetic susceptibility Renal insufficiency DM Hyperlipidaemia
What are the signs and symptoms of gout?
Sudden excruciating monoarticular pain
Peak at 24 hrs
Resolve over 7-10 days
Sometimes present with cellulitis, polyarticular or periarticular movement
Intercritical gout: asymptomatic period between attacks
Chronic trophaceous gout: Repeated acute attack - persistent low grade fever, polyarticular pain with painful trophi (urate deposits), urate urolithiasis
What are the investigations for gout?
Synovial fluid aspirate
- Monosodium urate crystals seen (Needle-shaped, NEGATIVE birefringence)
- Microscopy and culture to exclude septic arthritis
FBC - Leucocytosis
U&Es
Raised Urate
Raised ESR
AXR/KUB film - uric acid renal stones may be seen
What is Pseudogout?
Arthritis associated with deposition of calcium pyrophosphate dihydrate (CPPD).
Also causes acute monoarthropathy typically in larger joints in elderly patients
Also known as acute CPP crystal arthritis
What is the cause of Pseudogout?
Spontaneous and self-limiting but provoked illness, surgery or trauma
CPPD crystal formation initiated in cartilage located near the surface of chondrocytes
Linked with excessive calcium pyrophosphate, leading to formation of CPPD crystals
Shedding of crystals in joint cavity cause arthritic pain
What are the risk factors for Pseudogoutt?
Advanced age Injury Hyperparathyroidism Haemochromatosis Family history of CPPD Hypomagnesia Hypophosphatasia Gout Other metabolic conditions