Episode 3: Hurt doesn’t always mean harm

Hi and welcome to Episode 3 of the Flippin’ Pain Formula podcast. The central message of this session is that hurt does not always mean injury.

How do you understand pain? Take five minutes to think about the following two statements and see if you agree with them or not. Discuss this with your friends and family if you are listening as a group. Try to rate how much you agree with the statements on a percentage scale: for example if you completely agree, give it 100%, but if you are on the fence, go for 50%:

1) Pain only happens when you have injured yourself

2) The greater the amount of pain the greater the amount of injury.

Pause me now to do the task. Then when you are ready press play again.

I think most people would answer, “100% yes, I agree with these two statements”. As difficult as it is to believe, these statements are overly simplistic and, in fact, wrong. Here are some stories that show this.

There is a famous case published in the British Medical Journal, one of the most respected medical journals in the world. A builder aged 29 came to the accident and emergency department having jumped down onto a six-inch nail, which appeared lodged in his foot. The man was in agony. In trying to remove it, the smallest movement of the nail was excruciating despite being given fentanyl, a really strong pain medication. But when they cut away his boot, there was, miraculously, not a scratch on him. Unbelievably, the nail had passed between the toes and his foot was entirely uninjured. Flabbergasted, the man did the lottery that evening and won 80 million pounds. Well, OK, I made the last bit up the about the lottery, but the rest is true.

This is a perfect example of where you can experience terrible pain, despite having little or no injury. This phenomenon has been reproduced many times in laboratory experiments.

In the early nineties, a research study was carried out where volunteers were hooked up to a dangerous looking device straight out of ‘Dr Who’, with electrodes attached to their heads. They were told electrical current would be passed through their heads using the device and they would feel a headache. Half of the people reported that they did indeed feel a headache and when the volume button on the machine was turned up to 11 in full view of them. However, the device was a sham: it was not switched on, the volume button did not do anything, and at no point was electrical current passed through their heads. 

This is further proof that people can experience pain with little or no tissue injury. It is also proof that people will volunteer for some bizarre studies!

Now let’s consider the opposite situation, where people have received a terrible injury but experienced little or no pain. There are many recorded examples of this but here are just a few: Lieutenant Commander James Thake was shot in the leg during the Korean War, but it didn’t hurt until someone pointed it out to him. This sounds like an isolated incident, but it was not. In the Second World War, a famous field medical officer called Henry Beecher reported on hundreds of soldiers who had suffered serious combat zone injuries: Beecher found that 32% of those soldiers reported zero pain at the time of injury with only 24% reporting bad pain.

Similar stories come from shark attack victims, where it is not uncommon for them to report little or no pain at the time of the attack. Remember at the start I asked you if you think that the greater the amount of pain, the greater the amount of injury: if that was true then war wounds and shark attacks, which are catastrophic injuries by any measure, should always result in very high levels of pain. But that is just not the case.

Let’s think about more everyday situations. Have a think if you have ever come off a sports field to find that you were bleeding and asked yourself: “when did that happen?” Or have you ever woken up one morning and noticed a stonking great bruise on your leg with no recollection of when it happened?

All of these cases show that pain levels and severity of injury are not closely linked.

Here are some amazing individual cases.

The following was published in the scientific journal Injury Prevention in 2005. A 63-year-old Polish man suffering headaches and a lack of appetite was unaware that there was a 5-inch knife blade stuck in his head. When they examined him, doctors were shocked to find it. The man suspected he sustained the injury after falling off a kitchen stool when he was, let’s say, “a little tipsy”, but noticed no blood and had no major pain at the time. He later found the handle of his favourite knife, but the blade had mysteriously vanished. Doctors simply pulled the blade out without any complications, and he was sent home with a clean bill of health after only two days in hospital. There are countless similar stories in the popular media.

If pain only happens when you are injured, events like this should not be possible.

Finally, I would like to tell you about Hannibal. Hannibal works in the infamous Circus of Horrors and holds the Guinness World Record for pulling a four-tonne van over a 100-metre distance along Princes Street in Edinburgh with two meat hooks inserted through his back. There is a picture of Hannibal doing this and there is no sign of pain on his face, in fact he seems quite pleased about the whole thing. This is another amazing example of significant tissue injury with little or no pain.

Again, if pain only happens when you are injured, events like this should not be possible.

OK, right now, I think I know what you are thinking. You are thinking these are just freak events that don’t apply to everyday people like you and your pain. Well, that is where you would be mistaken. Let’s look at a group of everyday, normal people who experience a certain type of pain called ‘phantom limb pain’.

Phantom limb pain occurs when a person experiences pain in a limb that has been amputated. Terrible foot pain, even though the leg has been amputated above their knee. If pain only happens when you are injured, how can you have pain in a foot that you don’t have anymore?

Now, maybe you are thinking that this only happens in a few isolated cases. Well, have a guess at what percentage of people who have had an amputation, experience phantom limb pain.

The answer is 80%! A staggering 80% of people who have lost a limb experience pain in that limb and 60% still experience phantom limb pain one year after the amputation occurred. So, in this case you are unusual if you do not have pain in the limb that you do not have! Get your head around that!

Again, if pain only happens when you are injured, events like this should not be possible.

I hope that by now you will have reached the conclusion that pain does not only happen when you are injured, that it is far more complex than that. You can have pain without injury, and you can have injury without pain.

In addition, you will hopefully have reached the conclusion that higher levels of pain do not mean a higher degree of injury. You can have a terrible injury with no pain and terrible pain with no injury.

So why is this? I would like you to pause me here for a moment and write down why you think this might be the case in your notepad. Take five to ten minutes to consider some of the different stories. Why did the builder with the nail in his boot but a perfectly healthy foot have terrible pain? Why might someone experience little or no pain during a shark attack? Discuss these things with your friends and family if they are around. Once you have finished, press play again.

So why is this? Well, it comes back to the purpose of pain. The purpose of pain is not to tell you that you are injured. The purpose of pain is to protect you. Let me say that again: the purpose of pain is to protect you. Say it to yourself, out loud (or in your head will do fine if you are in the supermarket and would rather avoid awkward stares!): “The purpose of pain is to protect me”.

Another way of thinking about it is that pain is Darwinian: it wants to help you to survive. In all these situations, pain happened when it seemed biologically sensible or advantageous to have pain, irrespective of whether the tissues were damaged or not.

In the case of the nail sticking up through the builder’s boot, all the immediate evidence points towards a potentially life changing injury that, if left untended could result in mechanical damage so bad that the person might never walk again. The wound could bleed out, leading to significant blood loss or get infected ending up in the need for amputation. These are all extremely bad scenarios, and the builder’s brain weighed up the evidence at hand and decided pain was needed to draw attention to the problem and get something done about it sharpish. Pain occurred to protect him, and it did a wonderful job because it brought him to the emergency department. Only when there was sufficient reassurance that the foot wasn’t injured, did the pain subside.

In the case of a shark attack, where there would be a big wound with lots of blood loss and a similar risk of bleeding out and infection, there is also a good reason for protective pain: but there is the more dangerous immediate threat of surviving the attack! Imagine being incapacitated by pain, in the sea 10 meters from the shore with a hungry shark. That would not be very protective: and remember the real purpose of pain is protection. So, in these cases it is far more protective not to experience pain, to deal with the biggest threat and get out of the water and the immediate shark-based danger. Later, be that in minutes, hours, or days, pain from the wounds will be extremely protective, drawing attention to the injury and motivating the person to do something about it ASAP, or rest, so that the area heals. When you think about it, our alarm system is beautifully designed.

“Now, how does this wonderful pain alarm system work biologically?”, I hear you ask: that is an excellent question, and something we deal with in Episode 4. Needless to say, it is brilliant, but a bit complicated and not at all like what you might think!

We have covered lots of ground in this first part of Episode 3. The best way to learn this information is to take it on in bitesize chunks. So it’s time for a quick cuppa then when you are ready, come back.

OK, where were we: ah, yes let’s talk about scans.

I am going to focus on back pain for a moment. Not because there is anything special about back pain compared to arm pain or widespread pain, but just because it has been scientifically researched so much. In fact, a lot of what we know about persistent pain comes from studying people with persistent back pain. If you don’t have back pain, please don’t switch off as the messages apply to anyone with persistent pain: including you, yes, you!

Have you ever had a scan for your pain, whether that was an x-ray, or an MRI scan or indeed a CT scan? They all look inside your body to try and identify the physical cause of your pain. In one way, these scans are brilliant because if there is a serious medical pathology, such as a fracture, they will spot it. So, we certainly need scans in some cases. However, for over 90% of people with back pain, there is no identifiable structural injury. In these cases, scans can sometimes be a bit of a menace and actually lead to worse outcomes for patients.

“How is this possible?” I hear you ask. “How can simply having a scan lead to a worse outcome?” Time for another task.

If you have had a scan for your pain, please take five to ten minutes to jot down what the scan found. Also write down what the results made you think and feel: happy, sad, clear, confused, worried, relieved, upset, or delighted, and why. As always, discuss with friends and family if they are with you. If you have not had a scan, then think about how you feel about that. Also, state what you think a scan might show in your painful area. Please press pause now to do this task and then press play again when you are ready to go.

I will now use my great psychic powers to predict what the scan showed: did it tell you that your back pain was due to wear and tear? Or arthritic changes? Or osteoarthritis? Or facet joint degeneration? These are all different ways of saying the same thing.

Did it tell you that your discs have worn away with reduced disc height at L3 and L4? Or did it tell you that you had a disc bulging, protruding or slipped at L5?

I’d bet my bottom dollar that it showed some of these things, or something along those lines. But how can I be so sure?

Scientific studies have scanned healthy individuals with no back pain. Yes, you heard me, no back pain at all. The findings are pretty sobering and should make us all stop and think about the usefulness of scans, as well as the relationship between pain and tissue injury. In all age groups, often very high numbers of people have what the medical profession would classify as tissue injury but experience no pain.

Let’s look at 50-year-olds as an example. If you are in your 50s, then you have an 80% chance of having disc degeneration, a 60% chance of having a disc bulge and a 32% chance of having facet joint degeneration (or wear and tear), even if you have absolutely no pain. As we get older, these findings are even more common. Why do these people not have horrendous back pain? These could be described as false positives: they sound like terrible injuries and the source of considerable pain, but we know they are not because these people are pain free.

For those of you who have had a scan, take a look at your notes. What did the results say? If you have not had a scan, imagine that you are 50 years old with back pain and your scan showed disc degeneration, a disc bulge and facet joint degeneration: how would that make you feel about your back? A little worried I would guess. I would be if I was not given any background information.

Would you be less worried if you were told by the doctor that this was all normal for someone matching your age, even in those without any pain? Have a think about this: we will come back to it later.

As we come to the end of this podcast, I want to leave you with the key message that hurt doesn’t always mean injury.

In the case of persistent pain, pain bears little relation to structural damage or ongoing injury. People can have a lot of pain but little or no tissue injury, and vice versa.

And scans are not as useful as you might think in showing the cause of your pain, in fact they can be completely misleading.

Well done: you have made it to the end of Episode 3. See you for Episode 4.