What is the difference between ‘acute’ and ‘chronic’?

Simply put, in medical terms acute means short term and chronic means long-term. Either type of pain can be mild, moderate to severe. It’s important, however, to understand the difference between acute and chronic when discussing treatment for back pain for several reasons. The treatment and advice can vary considerably and the number of treatments, healing time and the expected treatment outcomes also very different.

The word ‘acute’ in the dictionary has several meanings; sharp or pointed, severe, and unpleasant as in an acute angle.

There is a lot of confusion around the use of these two terms. I often hear the expressions ‘I have chronic back pain’ or ‘my back pain is really acute’ when someone is just trying to describe how severe, excruciating or debilitating their pain is. In medical terms, this is not the case.

Acute Back Pain (short-term)

Acute pain can stop us in our tracks, cause pain and immobility, and prevent us from working or carrying on with our daily lives.  One example is an acute ankle sprain.

Acute back pain is usually a recent injury, perhaps sudden in onset; see treatment of acute back pain. Medically, it’s defined as a short-term injury, up to 6 weeks, commonly with sharp pain, muscle spasm, with inflammation and restricted movement, perhaps antalgia, but the pain usually settles more quickly. Chiropractic Treatment often works best at this stage and is excellent at achieving a faster recovery and helping prevent recurrence.

Subacute Back Pain

This is a term that has been used differently, and can describe the period of back pain between 6 and 12 weeks. It is also used for when the back pain has been strained slightly and the muscles give either warning twinges or feel weak as if they might spasm or the back might ‘go’ if you overdo it. This period is also when the back has been in the acute phase and is improving, but the injured muscles and ligaments have not fully healed, so they are weak and vulnerable to further strain.

Chronic Back Pain (long-term, or on-going)

Most back pain settles within 12 weeks. Hence, chronic back pain is when pain persists for over 12 weeks, or “pain that extends beyond the expected period of healing.” It comes from the Greek work ‘Chronos’ meaning time. Treatment emphasis is focused on managing the pain, and then, importantly, preventing the pain from recurring. This requires a far more in-depth understanding of the patient’s lifestyle and detailed understanding of what potential repetitive stresses and strains are the underlying causative factors. Please read Treatment of Chronic Back Pain for further information.

Back pain recovery times

Acute low back pain and sciatica usually recovers very favourably and is self-limiting.

  • 60% recover in 1 to 3 weeks;
  • 90% recover in 6 to 8 weeks; and
  • 95% recover in 12 weeks.
  • Serious causes of low back pain (e.g. cancer) are uncommon (less than 1%).

Acute and Chronic do NOT indicate severity

Neither term indicates how severe the pain is. You can have varying degrees – mild, moderate or severe – of either a short term or a long-term condition.

An acute pain, although sharp, can be mild (you can still work and keep active) or severe (where you literally can’t move and are stuck in bed in excruciating pain).

Chronic pain too may be mild, with a stiff back in the morning that wears off shortly after getting up, or some dull ache when you sit too long, or can be severe where you are simply living 24/7 with severe pain that leads you to take painkillers. Fortunately, this is very rare.

Most clients I see are in the mild/moderate category, or if it’s severe it’s usually only during the short, acute phase.

Many conditions are a mix of both acute and chronic.

This might be the first time you’ve had a sudden back spasm, so it’s purely acute, or it may just have been constantly painful or chronic for a long time. Often, however, you may have had a few recurring acute injuries, or on-going chronic pain with flare-ups from time to time;

Repeated acute episodes of back pain

You have repetitive acute episodes of pain that commonly last a couple of days to a week or that occur every few months/ 1-2 times a year/ every couple of years that may settle with self-care, or may require you to seek treatment.

Chronic ongoing back pain with intermittent acute episodes

You may have ongoing pain, tightness or stiffness every day, but then every so often, every few months or every year or so you have an acute episode that halts you in your tracks.

Treatment of Chronic and Acute Back Pain

I enjoy treating both types of back pain for different reasons. It’s great when I can get an immediate improvement in the client’s symptoms, if they’ve come in with acute pain. It’s also incredibly satisfying for me when I can work out, usually with longer discussions, what are the underlying causes of the Chronic ongoing pain and work on treating this.

Which heals faster, an acute or chronic back pain?

In simple terms, the longer a condition has been there, the longer it can take to heal. Yes, the same could be said of severity, the more severe it is, the longer it takes to settle, but this does depend on each individual case, and the cause. For example, a slight muscle strain will heal perhaps in a few days, vs a full rupture, for an Achilles heel injury. But again, for back pain with no specific onset or trauma, as I have explained in Your first Chiropractic Visit, it’s likely that a short-term acute injury will usually take fewer treatments than a Chronic or long-term condition.

  • Acute injuries are more likely to fully resolve quickly
  • Chronic conditions may heal fully but may require ongoing maintenance or preventative treatment.

Health Insurance Payments are usually for Chiropractic treatment of acute pain, not chronic

It’s very helpful to understand that most health insurance companies are usually happy to pay for a short set of treatments for an acute injury, but don’t cover Chiropractic fees for chronic or long-term conditions. If you are considering asking your insurance company to cover your chiropractic treatment, we recommend speaking to the Chiropractor beforehand.