Myalgia

Question 1

How can myalgia present in terms of distribution and duration?

Answer 1

Localised or generalised, acute or chronic.

Question 2

What are common causes of myalgia?

Answer 2

Infections (e.g. influenza), excessive exertion, and rheumatological conditions such as polymyalgia rheumatica.

Question 3

When are investigations not required in myalgia?

Answer 3

When a diagnosis can be made clinically.

Question 4

Which blood test should be checked if muscle damage or breakdown is suspected?

Answer 4

Creatine kinase.

Question 5

What guiding principle determines further investigations in myalgia?

Answer 5

They should be guided by the wider clinical presentation.

Question 6

What bedside test may show a false-positive blood result in rhabdomyolysis?

Answer 6

Urinalysis due to myoglobinuria.

Question 7

When might a respiratory viral swab be useful in myalgia?

Answer 7

When influenza or COVID is suspected.

Question 8

Which blood test may show leukocytosis or thrombocytosis in myalgia?

Answer 8

Full blood count.

Question 9

Why are U&Es important in suspected myalgia?

Answer 9

To look for hypokalaemia and assess for acute kidney injury due to rhabdomyolysis.

Question 10

Which blood test should be checked if hepatitis is suspected?

Answer 10

Liver function tests.

Question 11

Which inflammatory markers may be checked in suspected inflammatory or infective causes of myalgia?

Answer 11

ESR and CRP.

Question 12

When is a coagulation screen useful in myalgia assessment?

Answer 12

In haematoma or conditions needing surgical management (e.g. suspected compartment syndrome) or sepsis.

Question 13

Which blood test is raised in muscle damage from trauma or inflammation?

Answer 13

Creatine kinase.

Question 14

Which endocrine blood test should be requested if hypothyroidism is suspected?

Answer 14

Thyroid function tests.

Question 15

Which test is used to assess possible adrenal insufficiency in myalgia?

Answer 15

Early morning cortisol.

Question 16

Which vitamin deficiency may present with myalgia?

Answer 16

Vitamin D deficiency.

Question 17

Which serology might be useful in myalgia with suspected viral causes?

Answer 17

Viral serology such as hepatitis.

Question 18

When should blood cultures be taken in myalgia?

Answer 18

If the patient is unwell with fever or haemodynamic instability.

Question 19

Which autoantibody may be checked when systemic lupus erythematosus is suspected as a cause of myalgia?

Answer 19

ANA (antinuclear antibody).

Question 20

What imaging test is useful to assess muscular tears?

Answer 20

Ultrasound.

Question 21

What imaging may be used in suspected dermatomyositis and to guide muscle biopsy?

Answer 21

MRI.

Question 22

Which cardiac investigation may be required in some myopathies (e.g. mitochondrial myopathy)?

Answer 22

Echocardiography.

Question 23

Are imaging tests usually required in uncomplicated cases of myalgia?

Answer 23

No.

Question 24

Which specialty should myalgia patients be referred to if SLE is suspected?

Answer 24

Rheumatology.

Question 25

What is the general principle of managing myalgia?

Answer 25

Treat the underlying cause.

Question 26

Which treatment may be required for polymyalgia rheumatica?

Answer 26

Corticosteroids.

Question 27

Which surgical treatment is required for compartment syndrome?

Answer 27

Fasciotomy.

Question 28

What should be done if medication-induced myalgia is suspected?

Answer 28

Stop the causative drug and consider an alternative.

Question 29

What are the symptomatic measures for most cases of myalgia (e.g. exertion or viral infections)?

Answer 29

Rest, gentle stretching or massage, ice packs, simple analgesia (paracetamol or ibuprofen), topical analgesics such as NSAIDs or heat rubs.

Question 30

Which neurophysiology tests are used for suspected inflammatory or metabolic myopathies?

Answer 30

Electromyography and nerve conduction studies.