Amyotrophic Lateral Sclerosis (ALS)


  • Uncurable motor neuron degenerative disease
  • May present to ED as:
    • Abnormal gait (falls)
    • "Radiculopathy" (eps. cervical)
    • "Footdrop"/"Wristdrop" Saturday night palsy
    • Bulbar "event" (e.g. slurred speech or aspiration)
  • M:F = 2:1, any age (incidence rising with age)



  • 80% present with limb weakness ("amyotrophy" = muscle fibre atrophy), NB foot drop or loss of finger dexterity
  • 20% with bulbar symptoms, slurred speech, poor swallow, aspiration
  • Initial flaccid, then ±spastic cramps
  • Later cognitive and emotional fluctuations


  • Mixed UMN and LMN signs in different body regions
  • No sensory signs in ED

Differential Dx

Very early presentation may "mimic" others:

Investigations (in-patient)

  • EMG - Normal sensory, abnormal motor conduction


  • If suspected, admit neurology for workup and management plan
  • Consider, respiratory support, analgesia etc

Content by Dr Íomhar O' Sullivan . Last review Dr ÍOS 15/06/21.