Introduction to diseases of the musculoskeletal system

Question 1

Tendonitis

Answer 1

Tendon problem

Question 2

Bursitis

Answer 2

Inflammation of bursa

Bursae are synovial membrane lined pockets that serve to allow free movement of adjacent structures where otherwise, there could be friction

Question 3

Enthesitis

Answer 3

Inflammation of an enthesis

Entheses are the points where tendons, ligaments or joint capsules insert into bone

The largest site is the achilles insertion

Question 4

Osteoporosis

Answer 4

Reduced bone density

Question 5

Osteomalacia

Answer 5

Poor bone mineralisation

Question 6

Osteomyelitis

Answer 6

Bone infection

Question 7

Osteosarcoma

Answer 7

An example of malignant bone tumour

Question 8

Myalgia

Answer 8

Pain in muscles

Very common

Commonly associated with viral infections

Can be drug induced

Question 9

Myositis

Answer 9

Inflammation of the muscles

Far less common than myalgia and can be autoimmune

Question 10

Ways of classifying rheumatic disease

Answer 10

Articular vs non-articular/ periarticular

Inflammatory vs non-inflammatory/ degenerative/ mechanical

Number of joints affected

Duration of onset

Question 11

Joint pain

Answer 11

Periarticular

• point tenderness over the involved structure
• pain reproduced by movement involving that structure

Articular

• joint line tenderness
• pain at the end range of movement in any direction

Question 12

Joint inflammation nomenclature

Answer 12

Monoarthritis- affecting 1 joint

Oligoarthritis- affecting 2-4 joints

Polyarthritis- affecting 5 of more joints

Question 13

Importance of rheumatic disease

Answer 13

Common and getting more common

Expensive

Important

Leading cause of disability

Question 14

UK impact

Answer 14

Third greatest impact on the health of the UK population, considering both death and disability

• MSK disorders account 15.6%
• low back pain accounts for over half of this
• ranking of major causes of death and disability

Question 15

MSK disorders and work

Answer 15

Poor musculoskeletal health is a major barrier to workplace participation

People with MSK conditions are less likely to be employed than people in good health and more likely to retire early

Question 16

Septic arthritis

Answer 16

Always think about it in a patient with a (usually) single, hot and swollen joint

Mortality rates are of 11%, increases to 50% in polyarticular disease with sepsis

Commonest organisms are staph and strep

Do not have to be systemically unwell and they may be able to weight bear

Question 17

Gout

Answer 17

Crystal deposition is often clinically silent

About 10% of people with hyperuricaemia develop clinical gout

UK GP studies show the prevalence of gout per 1000 has been steadily increasing from 2.6 in 1975 to 3.4 in 1987, and 9.5 in 1993

Clinical cure is achievable with treatment which is cheap, widely available, and under prescribed

Question 18

Who gets gout?

Answer 18

Men aged 40 years and over

Women over 65 years

It increases with age, affecting 15% of men aged over 75 in the united kingdom

Epidemiology studies show that the metabolic syndrome and its components are strongly associated with gout

Question 19

Risk factors for gout

Answer 19

Male sex
Older age
Genetic factors
Chronic kidney disease
Metabolic syndrome
Osteoarthritis 
Dietary factors

Question 20

Crystals

Answer 20

Gout is caused by negatively birefringment rods- monosodium urate

Pseudogout by positively birefringent rhomboids- calcium pyrophosphate

Question 21

Management of gout

Answer 21

Acute attacks

• NSAIDs
• colchine
• steroids

Long term

Urate lowering therapy

Question 22

Rheumatoid arthritis

Answer 22

Common, chronic, multisystem inflammatory condition affecting up to 0.5-1% of the world

More common in women (3:1)

Peak onset is 45-65 years

Unknown cause with around 30% genetic susceptibility and the rest environmental

Question 23

Main problem with inflammatory arthritis

Answer 23

Synovium

Question 24

Main problem with osteoarthritis

Answer 24

Cartilage

Question 25

Rheumatoid arthritis pathophysiology

Answer 25

Early lymphocyte invasion of the synovium Acute inflammatory reaction- swelling and increased vascular permeability Synovial proliferation Pannus formation Cartilage destruction and bone erosion

Question 26

Symptoms and signs of pathophysiology

Answer 26

Onset varies, can be acute or chronic Symmetrical pain and boggy swelling of the small joints of the hands and feet Early morning stiffness > 1 hour Malaise and fatigue Systemically unwell Examination- look for pain, swelling and restriction of movement Also really important to examine other organ systems as RA is a systemic disease

Question 27

Extra-articular manifestations of RA

Answer 27

Nodules Bursitis/ tenosynovitis Eyes: dry eyes/ scleritis/ scleromalacia Splenomegaly Anaemia of chronic disease Lung fibrosis/ effusion Pericarditis Neurological: atlanto-axial sublaxation/ carpal tunnel syndrome Renal amyloids Lef ulcers/ pyoderma gangenosum Vasculitis Increased risk of CV disease

Question 28

Rheumatoid arthritis invesitgations

Answer 28

ESR and CRP FBC: anaemia of chronic disease Rheumatoid factor positive- IgM antibody against the FC portion of human IgG antibodies Anti CCP antibodies X-rays: normal in early disease... erosion/ peri-articular osteoporosis and reduced joint space/ cysts

Question 29

RA principles of management 1

Answer 29

Early and aggressive treatment to reduce inflammation and joint damage Non-steroidal anti-inflammatory drugs for short periods Corticosteroids - intra-articular joint injections if only 1 or 2 troublesome - systemic if many joints are a problem

Question 30

RA principles of management 2

Answer 30

Disease modifying anti-rheumatic drugs Synthetic DMARDs - methotrexate - hydroxychloroquine - leflunomide Biological agents - anti TNF agents - anti B cell - anti interleukin 6 receptor blockers - anti T cell- selective co-stimulation modulator - janus kinase inhibitor

Question 31

RA principles of management 3

Answer 31

Multidisciplinary team input - nurse specialist (education and disease monitoring) - physiotherapy (improve strength and stamina) - occupational therapy (work, home environments) - podiatry

Question 32

Osteoarthritis

Answer 32

Common, degenerative disease of which the prevalence increases with age Affects 70% of over 65 year olds Most commonly clinically affects the knees, hips and small joints of the hands Characterised by joint pain and very variable degrees of functional limitation

Question 33

Pathophysiology of osteoarthritis

Answer 33

Metabolically active, dynamic process, involving all joint tissue (cartilage, bone, synovium, capsule, ligaments/ muscles) Focal destruction of articular cartilage Remodelling of adjacent bones- hypertrophic reaction at joint margins Remodelling and repair process (efficient but slow) Secondary synovial inflammation and crystal deposition

Question 34

Clinical features of arthritis

Answer 34

Age > 50 years Morning stiffness < 30 minutes Persistent joint pain aggravated on use Crepitus No inflammation Bony enlargement and/ or tenderness

Question 35

Systemic lupus erythematosus

Answer 35

Chronic, relapsing, remitting disease Broad spectrum of clinical features involving almost all organs and tissues Prevalence in the UK 97 per 100000 F:M is 10-20:1 Peak onset between 15-40 years More common and severe in those of Afro-Caribbean, Indian, Hispanic and Chinese origin living in USA and Europe

Question 36

SLE investigations

Answer 36

Urinalysis- urinary protein: creatine ratio Full blood count Urea and electrolytes ESR CRP Liver function test Antibodies: ANA; ENA; Anti-dsDNA; lupus anticoagulant; anti C1q; C3, C4