Myalgia (muscle pain)

Question 1

What are the 2 ways in which myalgia can present in patients, in terms of radiation?

Answer 1

Localised or widespread

Question 2

What are the 2 ways in which myalgia can present in patients, in terms of exacerbating symptoms?

Answer 2

Worse during movement or rest

Question 3

What are the 2 ways in which myalgia can present in patients, in terms of how constant the pain is?

Answer 3

Occurs for several minutes before disappearing or is always constant

Question 4

What usually determines how myalgia presents in each patient?

Answer 4

The underlying condition that is causing myalgia

Question 5

If a patient with myalgia also presents with fever, what 3 underlying conditions are suspected?

Answer 5

Sepsis, infection, pyomyositis

Question 6

What is pyomyositis?

Answer 6

Bacterial infection of muscle that results in abscess formation

Question 7

If a patient with myalgia also presents with hypotension, why is this a red flag?

Answer 7

Hypotension could indicate sepsis, which needs to be confirmed and treated immediately

Question 8

What is postural hypotension, and if a patient with myalgia presents with this what underlying condition is suspected?

Answer 8

Blood pressure suddenly drops after standing up from sitting/lying position

Presents in Cushing’s disease

Question 9

If a patient with myalgia also presents with cutaneous lesions, what 5 underlying conditions are suspected?

Answer 9

PsA
Systemic lupus erythematosus
Endocarditis
Vasculitis
Lyme disease

Question 10

If a patient with myalgia also presents with joint inflammation in peripheral joints, what 3 underlying conditions are suspected?

Answer 10

RA
PsA
SLE

Question 11

If a patient with myalgia also presents with tender/trigger points, what 2 underlying conditions are suspected?

Answer 11

Fibromyalgia
Myofascial pain syndrome

Question 12

If a patient with myalgia also presents with limited active movements and slightly limited passive movements, what soft tissue injuries are suspected?

Answer 12

Bursitis
Tendonitis
Strain
Sprain
Overuse injury

Question 13

If a patient with myalgia has the underlying condition hypothyroidism, what 4 other symptoms can they present with?

Answer 13

Hoarse voice
Delayed relaxation of reflexes
Slowed speech
Dry skin

Question 14

If a psychological condition is they underlying cause of myalgia in a patient, give 3 examples of the observed behaviour of the patient?

Answer 14

Depressed/tense/stressed state

Question 15

What is the initial investigation of myalgia?

Answer 15

It is a diagnostic process to determine what underlying condition is causing the myalgia

Question 16

Why is it important to check patient history when initially investigating myagia?

Answer 16

Past incidents and activities that could have triggered myalgia

Past/current medications and side effects

Family conditions

Allergies

Question 17

What are the 3 initial lab investigations for myalgia?

Answer 17

Full blood count
Renal function
Liver function

Question 18

If sepsis is suspected, what lab investigation is done?

Answer 18

Blood culture is sent to lab, can also be tested for another infection

Question 19

In lab investigations of myalgia, why is the creatine kinase test performed?

Answer 19

Elevated serum creatine kinase (CK) can indicate muscle damage

Question 20

In lab investigations of myalgia, what do elevated levels of ESR and CRP indicate?

Answer 20

Systemic inflammation, which suggests presence of infection or inflammatory diseases

Question 21

In lab investigations of myalgia, what underlying condition can be indicated due to normal ESR level?

Answer 21

Fibromyalgia

Question 22

What 3 body fluids can be used for the cortisol test, and in a patient in myalgia what do elevated cortisol levels indicate?

Answer 22

Cortisol test can be performed using blood, salvia or urine

Elevated cortisol level suggests Cushing’s disease

Question 23

Why should autoantibody testing be performed only if a particular underlying condition is suspected in a patient with myalgia?

Answer 23

Widespread testing in all patients with myalgia can produce high rate of false-positives

Question 24

What are ANA test, and what condition are they elevated in?

Answer 24

Antinuclear Antibody test, elevated level in SLE

Question 25

What is the ANCA ELISA test, and what underlying condition is it used to diagnose, that causes myalgia in patients?

Answer 25

Anti-Neutrophil Cytoplasmic Antibodies (ANCA) ELISA test: autoantibodies that target neutrophils, are present in ANCA-associated vasculitis

Question 26

In lab investigations of myalgia, what does presence of RF and anti-CCP suggest?

Answer 26

RA is possible underlying cause of myalgia

Question 27

Is radiological investigation necessary in diagnosis of underlying cause of myalgia?

Answer 27

Not necessary, but can be used to assess damage caused by inflammatory arthritis, muscle disease, fractures, soft tissue injuries

Question 28

What 4 imaging mediums are commonly used in radiological investigation of myalgia?

Answer 28

X-ray, CT, MRI, ultrasound

Question 29

What 2 neurophysiological investigations are performed when particular underlying causes of myalgia are suspected, and what are these causes?

Answer 29

Electromyography and NCDs used to measure electrical activity in nerves supplying painful muscles if neuropathic process due to inflammatory/metabolic myopathy is indicated

Question 30

What are the 5 types of key differential diagnosis for myalgia?

Answer 30

Mediation-induced myalgia Soft tissue injury Infection Autoimmune disease Neurovascular disorder

Question 31

What is the initial management of myalgia, until the underlying condition is diagnosed?

Answer 31

Use conservative treatments, watchful wait and treat symptomatically if needed

Question 32

Give 3 examples of conservative treatments used for initial management of myalgia?

Answer 32

Rest and elevate painful muscle Alternate between ice and heat to decrease swelling and inflammation (ice) and improve blood flow (heat) NSAIDs

Question 33

Give 4 examples of differential diagnosis of myalgia, which are autoimmune diseases?

Answer 33

Inflammatory arthritis SLE Vasculitis Pyomyositis

Question 34

Give 4 examples of differential diagnosis of myalgia, which are infections?

Answer 34

Malaria Lyme disease Sepsis Cold and flu

Question 35

Give 5 examples of differential diagnosis of myalgia, which are soft tissue injuries?

Answer 35

Strains Sprains Tendonitis Bursitis Myofascial pain syndrome

Question 36

Give 4 examples of medications that can cause medication-induced myalgia?

Answer 36

Statins Chemotherapy Radiotherapy High bp drugs such as ACE inhibitors

Question 37

Give one example of a neurovascular disorder that can cause myalgia?

Answer 37

Spinal Muscular Atrophy (SMA)

Question 38

When would you obtain muscle biopsy/aspiration from a patient presenting with myalgia?

Answer 38

Patients with suspected abscess, inflammatory myopathy, vasculitis, or SLE