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Content is anchored to trusted sources where available, but Compass has not yet been clinically reviewed. It provides general information rather than medical advice.

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Symptoms and clinical language

Limb onset

Describes ALS/MND that began with changes in an arm or a leg.

What it means

The first symptoms were in a limb, such as a weak hand, a dropped foot or a change in grip. Like bulbar onset, it describes the starting point rather than the whole course.

Why you might hear it

  • It is recorded in your notes and used in research groupings.
  • It may be written as spinal onset, which means the same thing.

People who may help

Where Compass goes into this

About this explanation

These are plain explanations of words you may come across, not advice about your own situation. Where a word matters to a decision, the question pages go into it properly, and your own team is the place to take it.