Acute Pain (Less Than 3 Months)

The vast majority of us grow up with pain as part of our day-to-day existence. Most of the time we get pain when we’ve knocked, banged or injured something. This type of pain is generally termed ‘Nociceptive pain’ and is usually also called ‘Acute Pain’ .

Acute pain has to occur first before persistent pain; as persistent pain means that the pain has stayed.

Our body has sensors all over it & inside it. These sensors sense mechanical stimulation, temperature change or chemical change. We also have some special senses like vision, hearing, smell etc but we’re generally more concerned about our touch/feel part of the nervous system when it comes to body pain.


Our pain system detects the same mechanical stimulation, temperature change or chemical change, but it’s only meant to get excited when something stimulates it well outside the normal range e.g. very hot water, big knock or bang etc. When they do sense abnormally intense stimulation, they fire off pain messages down the nerves, which go all the way to the spinal cord in the backbone. The nerves join with the spinal cord & the messages then get processed & sent up to the brain where we then can localise what & where it is we are feeling.

If we injure ourselves, our body is great at repairing it. The immune system recognises that we’re damaged, and releases lots of chemicals around the area. These chemicals signal to repair cells to sort it all out. A really clever thing happens to our nerve endings during this repair. The chemicals that signal the repair cells also make the nerve ending lots more sensitive than they would be normally. This means that the injured bit is very sensitive and therefore painful. Why’s that clever we might ask? It’s natures way of saying, ‘I’ll heal it better if you keep it still, so I’m gonna make it painful to stop you moving it’ – Brilliant isn’t it!

When the injury heals & all the chemicals go away, usually the nerve endings also to get back to normal sensitivity and everything is fine.

This is how acute pain works.