The Aword

  • Increase font size
  • Default font size
  • Decrease font size

Muscle Pain

E-mail Print PDF


There are various subtypes of muscle pain:

  • Pain onset during exercise: may be due to exhaustion of fuel supply to the muscle, or build-up of lactic acid
  • If there is a metabolic defect, or vascular ischaemia (reduced blood supply) then normal exercise may not be painful (but blood CK may be high).
  • If normal exercise is painful and the blood tests are normal, then this might indicate either structural damage (muscle/tendon/joint/bone) or a Polymyalgia syndrome.
  • If pain onset is hours after exercise and lasts up to 5 days, and the blood CK is raised, this might suggest a myopathy (abnormality in the muscle), especially disorders in which there is rhabdomyolysis (muscle breakdown)
  • Pain unaffected by exercise may indicate: Polymyalgia, Drugs/ Toxins or certain types of polyneuropathy.
  • Cramps : may be associated with drugs such as : Caffeine, Diuretics(water tablets), Labetalol, Lithium, Nifedipine, Terbutaline, Tetanus, Theophylline, Vitamin A) They are also a very common feature of arachnoiditis.
  • Pain with prolonged immobility.
  • Central Nervous System related: Restless legs; Upper motor neuron disorders; Dystonias (many arachnoiditis patients have abnormal muscle tone : dystonia, and restless legs syndrome is common; spinal cord involvement constitutes an upper motor neuron disorder and this is associated with spasticity: increased muscle tone)
  • Fatigue syndromes: Chronic fatigue; Depression

Typical evaluation for generalized muscle pain or discomfort:


History: Precipitating factors; Nature & Location of pain.


Examination: Strength; Sensory loss; Trigger & tender regions; Endurance.

Laboratory tests

  • Blood: blood count; ESR (a non-specific sign of inflammation); CK, creatine kinase: a measure of muscle inflammation; potassium; calcium; Phosphate; thyroid function; Connective tissue antibody screen (ANA)
  • EMG (electromyogram) & Nerve conduction studies
  • Muscle biopsy: if indicated by other abnormal test results.
  •  ? Exercise testing:  Lactate after mild exercise