Jonathan

Can We Rely on the Interpretation of MRI Scans?

MRI scanners are a wonderful invention and continue to advance, giving us finer and finer pictures of our anatomy. As is typical with all fast-improving technology, the human aspects, the culture, struggle to keep up.

An MRI scan means nothing without an interpreter. It’s a language most of us don’t speak. Ordering a scan presupposes that there is someone to say what it shows and crucially, what it means for the patient. Someone has to put the patient’s story, the examination and the scan together and form a conclusion about what the next step is.

The developments in machine learning mean that reading x-rays and MRI scans will soon be done by machines. The consistency of analysis this promises will still not be enough if there is no one to sit down with the patient and discuss the results.

But this post is about the consistency of analysis of MRI scans. The ‘someone’ in these cases is a radiologist. Radiologists are highly trained doctors who specialise in imaging and in various types of interventions where imaging is used.

Since radiologists are human we should expect variation in the way MRI scans are interpreted. But how much?

The Study

A 63-year old woman with a history of low back pain and right leg pain in a particular pattern was sent to 10 different imaging centres and given MRI scans for her problem. The centres were unaware that she was being scanned anywhere else.

The researchers looked at what the radiologists reported each time for the same scans and the results were very illuminating.

In the 10 reports they found 49 distinct findings reported for the scan (disc protrusion, facet joint arthritis etc). 16 of those findings only occurred once across the ten scans, in other words the other nine radiologists did not report that finding. None of the 49 findings occurred in every scan report, making us wonder about the validity of the findings.

Highly skilled and highly trained radiologists were doing the best job they could in reporting on these scans. But the results were so variable and inconsistent that it calls the process into question. How can we make important decisions about a patient’s medical intervention if the scan finding are unreliable?

The scan looks so solid, on the screen in black and grey and white. It’s hard to accept that we might all see very different things and come to very different conclusions about what to do next for a person in pain.

And that’s without even considering the matter of what the scan results mean for our future, should they be valid in the first place. That’s next.

Reference

Herzog, R., et al. (2017) Variability in diagnostic error rates of 10 MRI centers performing lumbar spine MRI examinations on the same patient within a 3-week period. The Spine Journal, 17(4), 554-561.

Continue with Magnetic Resonance Illusions Part 3.

The New Magic Lantern

The magic lantern, an early type of image projector, was developed in the 1600s and used through the 1700s to the mid-20^th century when it was replaced by the slide projector.

The horror theatre genre “phantasmagoria” used magic lanterns to project demons, ghosts and skeletons onto walls as part of their shows. An obsession with the bizarre and the supernatural characterised the romanticism of the latter decades of the 18^th century, including the popularity of the gothic novel.

The new romanticism of the 21^st century surrounds technology and its controlling sister, the computer algorithm. Exchanging the supernatural for the super-technological, we watch magic images play on screens in our homes and in our hands.

The demons we project on our screens are no longer figments of a fearful imagination but images of ourselves cut into slices. We have digitised our layers and seen what we are made of in black and white.

The MRI scanner is the new magic lantern, providing vivid and detailed pictures of what it is to be us. And we take it all at screen value, it’s there in way over fifty shades of grey so why shouldn’t we?

The MRI scanner is amazingly useful in a large number of ailments, allowing doctors to diagnose serious conditions, but when it comes to musculoskeletal problems it’s just not so reliable. And in back pain and neck pain, it can be downright misleading.

Continue with Magnetic Resonance Illusions Part 2

It’s time to talk. What have we lost in the race to manage capacity and throughput?

I don’t have to repeat the stats. We’re spending more and more on the assessment, treatment and management of musculoskeletal (MSK) pains. We’re doing more scans, more innovative investigations, more new treatment ideas, more new ways to surgically improve our moving parts.

And all this spending and brainpower is having a good result? Is MSK care timely, appropriate and effective? Unfortunately, not. It doesn’t look like we have done, or are doing, a good job. Disability and costs climb in unison with the efforts to deal with the problem.

It’s difficult to tease out the correlations from the causations here but one thing is clear: we need to consider changing the paradigm we’re operating under. More of the same is not working.

Most consultations for pain in the UK occur with a GP and the average time spent in that appointment is seven to ten minutes.

Is seven to ten minutes enough? Well, that depends on what you are aiming to achieve. A doctor’s role is diagnosis and the diagnostic model has been astonishingly successful at keeping us alive against a number of challenges.

What’s the Diagnostic Question in a Spinal Assessment?

There are two questions here, both relatively quick to answer:

• Does the patient have a medically important condition and need treatment or referral to a specialist? This group is smaller than 5% in number and includes many medical conditions including inflammatory arthritis, infections and tumours.

• Does the patient have a specific spinal-related condition? This is again fewer than 5% in numbers and includes nerve root impingements and spinal stenosis.

Once those diagnostic questions have been answered by a doctor, there is little more to do under the diagnostic model. The patient has back pain or neck pain. Chasing after a closer diagnosis reaps diminishing returns as it has little or no effect on the choice of treatment given to that person.

This group makes up 85-90% of spinal pain sufferers, yet we concentrate on the specific conditions such as cauda equina which, although very important to identify, make up a very small part of the whole.

What Should We Assess in Spinal Pain?

Physiotherapists and doctors love the hard stuff. The stuff we can feel, the muscles we can test, the reflexes we can elicit, the movements  and images we can see.

However, the aspects of a person which relate to severity of disability, likelihood of recovery and return to normality are all psychosocial. No physical parameter makes much difference unless it is severe in nature.

We assess spinal patients using the measures that don’t have relevance to their recovery. Yes, they’re quick and once you’ve learnt the techniques, not that difficult. You learn how to handle a patient as a physiotherapist, that’s what we do.

The Driving Forces Behind Musculoskeletal (MSK) Management

What drives MSK management across the country is numbers and capacity. The steadily increasing demand for help with back, neck and other pains puts continual pressure on NHS systems to cope with the numbers.

New initiatives invariably revolve around how to get larger numbers through the gate, how to reach targets so that this percentage of patients is catered for in that amount of time. Success is throughput.

Physiotherapy assessment times have traditionally varied from 30 minutes to an hour. In response to pressures new times have been suggested: 15 minutes or 20 minutes to assess, form a plan, record this and send the patient on his or her way. These look like responses to pressure rather than reasoned approaches. At these times our input becomes diagnostic rather than therapeutic.

What this all misses, and what questions the validity of the entire process, is any mention of outcome, any focus on whether the patient is better or not, any indication that the assessment and treatment have been successful. Even a 60-minute assessment is all very well, but what was the result in the patient’s life?

Upstream vs Downstream Costs

Musculoskeletal care is expensive. But we do have a choice about the amount, the timing and how much we can control those expenses.

At present, we do cheap MSK care upstream, closer to the initial presentation. A short GP consultation establishes the presence of non-serious back pain, a short course of 30-minute sessions of physiotherapy attempts to improve things.

A number of patients will resolve or not re-consult, but those who continue to request help begin to go towards secondary care. More expert physiotherapy, MRI scans, spinal injections, orthopaedic opinions and surgery are possibilities.

This process is much less controllable and, added to the costs in suffering, work loss and benefits paid, makes up the greatest proportion spent on this group of patients. Here are the uncontrolled, and at present mostly uncontrollable, downstream costs.

Assessment Takes Time & Can’t Be Rushed

If we are to assess the psychosocial parameters of relevance to a person’s spinal pain, it’s going to take time. Quite a lot of it. An hour to start with to tell their story and feel that they have been heard.

“No-one listened. No-one understood” are common themes from patients who go through the system. There is no substitute for extending the time to find what is driving the patient’s symptoms if we are going to have any effect.

By investing in upstream time we can target three main aims:

• We can find and address the drivers of a patient’s pain
• We can measure their outcomes to see if we’re doing anything useful
• We can try to limit the uncontrollable downstream costs.

This should lead towards what is lacking from present spinal care, effectiveness. Without a measure of effectiveness, all our targets, capacity and throughput have no meaning.

A Problem with Musculoskeletal Diagnosis

The patho-anatomical medical model, searching for the tissue at fault and aiming the therapy at that fault, has served us well. It works very effectively in much of medicine, in cancer, infection, heart disease and a myriad other conditions.

It’s primarily in musculoskeletal diagnosis where this link breaks down, that the diagnosis becomes less relevant, that the treatment does not fit the crime, so to speak.

There is a spectrum in MSK disorders, from where the diagnosis is vital and accurate to where the diagnosis is speculative and arguably spurious.

Unfortunately, this spectrum is not well recognised in the management of these disorders and musculoskeletal diagnosis continues to be pursued in cases where it is unnecessary or potentially harmful.

Diagnosis must serve the purpose of identifying a potential tissue target for intervention and indicating which intervention would be most appropriate. If it cannot identify the tissue at fault with reasonable probability, or does not point us towards the treatment, it does not have a use.

Trauma – High Certainty, Clear Treatment

A man mis-steps on the edge of a kerb, going over on his ankle. He hears the crack, the foot swells and he can’t bear weight on it. The pain is significant and immediate. Tissue damage has occurred.

The x-ray shows a fracture of the lateral malleolus, the bony prominence on the outside of the ankle. The ankle ligaments have held against the force of the fall, but the lower part of the fibula has parted from the upper, removing the stabilising mortise from the ankle joint.

The bones must now be held in position and in close proximity for long enough so that they knit sufficiently. Five or six weeks in a cast, usually with weight bearing allowed at some point, restore the stability of the ankle and allow normality to return.

Trauma – Moderate Certainty, Clear Treatment

A young woman pivots as she runs towards the ball. She feels her knee give way with pain and collapses onto the pitch. Her knee swells quickly and she finds bearing weight difficult.

Initial diagnosis is an anterior cruciate ligament (ACL) injury. The knee is treated with ice, compression and rest for a few days, progressing to the restoration of muscle control and knee bending as the swelling and pain ease.

An examination from a knee specialist two weeks after the injury shows some laxity of the anterior cruciate ligament. The provisional diagnosis is an ACL strain and an MRI shows some changes that support that hypothesis.

?Trauma – Low Certainty, Unclear Treatment

A man bends over to pick something up. It’s very light and he has a job where he does quite a bit of heavy work so it should be easy. He gets severe back pain. GP consultations and local physiotherapy make no progress.

A spinal opinion diagnoses low back pain and an MRI scan shows degenerative changes in the lower two lumbar segments.

It is now three months since he worked. Spinal injections are suggested or a discectomy to deal with one of the minor bulges seen on the scan. He is heading for long term pain and disability.

Back Pain Diagnosis

10-15% of back pain patients have a substantive diagnosis, either of a serious medical condition or a specific back pain condition such as a nerve root compression or spinal stenosis.

All the rest are left with nothing.

By nothing I mean that we know they are not seriously ill and they don’t have a particular condition we can pin down. A diagnosis by exclusion is not really a diagnosis at all. It’s a description – “You have low back pain”.

And that’s 85% of all back pain sufferers! 85% for whom the diagnosis has no relevance as it never points to a particular treatment with good evidence of effectiveness. I’ll go over the plethora of back pain treatments another time.

Concentrating on diagnosing, on imaging, on investigating in this group of people seems to have little validity. And if we do come up with a diagnosis, if it doesn’t change the treatment or outcome for the better then it’s an example of spurious diagnostic accuracy.

MRI Scans

The gold standard of imaging, the MRI scan, doesn’t show what’s wrong in low back pain. It shows a lot of things, but we have no way of knowing which are relevant to the person’s pain in most cases.

Normal people, by which I mean people who have never had low back pain, show what we typically call significant spinal changes on MRI scanning. As these are not painful by definition, how are we to decide on the relevance of such changes in people with low back pain?

For the vast majority of back pain sufferers, chasing a patho-anatomical musculoskeletal diagnosis, either as a surgeon or as a physiotherapist, seems to be a losing play.

Patients need a functional diagnosis and to have attention paid to the characteristics which define how they are and how they will be. Those characteristics are mostly psychosocial and they take time to unravel.

Another time I’ll talk about time and how we might improve back pain assessment and management.

I’ve been back in the gym for the last six months. I love pushing iron, the clank of the weights, the rubber matting, the whole thing. As it’s some time since I worked out and I’m not that young anymore, I’m mostly using machines as I ease in.

I aim to increase my strength and muscle mass and decrease the gut. Loss of muscle mass can start around age 30 if we are inactive. When we get to sixty years of age we lose around 1% of our muscle mass each year. By 70 it’s 2% per year, by 80 it’s got to 4%. I’m 61 by the way.

Like interest on a loan, this is not so much in one year, but year in and year out it builds up into a big debt. Muscle weakness can then make it much harder to go up stairs, rise from a chair, manoeuvre into a car or get up off the floor.

It doesn’t matter how old we are, we can still increase strength and muscle bulk by training. Sure it’s easier when we are younger and we don’t have to work round so many painful joints. But we still have to do it right.

Muscle bulk and power increases in response to the intensity of the resistance we work against. If we don’t use enough resistance, we don’t get any change.

I was shocked by how many people are still doing their exercises badly! Young and old, they did their workouts with no clear idea what they were trying to achieve or how to do it. All the errors I saw years ago are still there. I thought perhaps that techniques would have improved as people had access to more information, but not so.

The guys and girls that are doing well could do so much better. People not doing well could start to gain. Older people could enjoy the strength and health benefits they are attending for. Otherwise they are pretty much wasting their time.

Here are my 14 gym mistakes holding you back, and why. Some of them are pretty obvious, others I probably just have a thing about.

1. Don’t chat all the time. If you want to go the gym with your mates and chat, that’s fine. Just don’t expect to gain any muscle. By all means go with the banter and joking, but are you there to work hard or not? You can do both. Or not. And please don’t get in the way.

2. Leave your smartphone in the locker. I love my smartphone, I have an iPhone 6 Plus and use it loads. But nothing has ever appeared on it that demanded my attention then and there, or else. And I reckon that’s true for pretty much everyone. Are you there to train or not? Bringing one into the gym advertises you’re not serious. One of the guys recently smashed his nice water bottle by dropping a dumbbell on it. It’s gotta happen to a phone some day…

3. Stop messing with your water bottle. Yes, I know hydration is important and our performance might drop X% if we lose this or that amount of water. But I doubt very much hydration is the factor limiting improvement for almost anyone in the gyms I’ve been to. Drink a good bit before you go in and, unless you sweat a whole lot, you don’t need extra fluid. It’s a distraction. Focus.

4. Don’t sit on the machine, doing nothing. There’s plenty of time in-between your sets for someone else to do their set in time for your next one. This is especially important when there’s only one of that particular equipment in the gym. Don’t be a machine hog and have some respect. Sharing is good.

5. Don’t go macho on weights. This is more a problem with younger guys who want to look like they’re shifting some serious iron. Throwing weights about is a bad idea. Apart from being ineffective. Do I have to explain? Injury, my man. See below.

6. Be nice to your tissues. The body systems that matter to us in the gym are the muscles, tendons, ligaments and joints. Muscle tissue remakes itself completely in 90 days, replacing all the molecules, proteins and chemicals, with “new” ones. This allows it to adapt quickly and so strength can increase dramatically in a relatively short time.

7. Connective tissue takes much longer to adapt. Connective tissue (tendons, ligaments, fascia) is not the blood-rich and metabolically active environment that muscle is. It takes much, much longer than muscle to adapt, to renew itself to face the new challenges you are putting on it.

The time? Around 210 days, or seven months. During this period, if you are increasing your muscle power dramatically, the gap between the power your muscles can exert and what your connective tissue can cope with is widening dramatically. This is a recipe for trouble.

Trouble like tennis elbow, biceps tendonitis, patellar problems or shoulder tendon irritation. Make haste slowly is the key, especially if you are young and can make haste fast.

8. Use the full range. This is one of the most common sins. But can we really use the full range of the muscles or joints we are training? Well no, there are loads of reasons why that’s not entirely possible. But that doesn’t make it right to do the opposite. Yea, I’m on my high horse now.

So how do you spot this error? Look for anyone who’s swinging a weight or can’t let it down the whole way. Biggest losers here are people trying to do a one arm curl over an incline bench. They choose a weight way too heavy and can’t let it down beyond 90 degrees elbow bend cos they don’t have the strength. Ha.

Or the leg extension machine, where they don’t start far enough back into knee bend and don’t straighten the knees at the end. Doing this is going to strengthen you sure, but only through a very limited part of the movement. And one of the most important bits is right to full knee straight.

Machine movements are limited enough as it is, why make them even less effective?

9. Don’t waste being eccentric. When you start a barbell curl, the barbell is at the bottom of the movement and resting against your thighs. OK?

When you make the curl movement up as far as you can go, that is known as concentric contraction. The muscle is shortening, balling up, as you curl that weight up. Now it’s time to let the weight down. As you do this, your biceps is still contracting but lengthening at the same time as it pays out against the weight.

This is called eccentric contraction and may be more important for strength and mass development than concentric. So don’t waste it. Let the weight down slowly.

It’s half of the exercise so make your muscle do the damn work. You’ll be happy with the results.

10. Don’t hang about between sets. If you wait more than 45-60 seconds between sets your muscles recover too much to easily ramp up the intensity that will make them grow. I’ve seen a boy on the leg extension machine fiddle with his phone for five minutes between sets. He might as well come in and do one set on Monday, another on Tuesday etc. for all the good that will do.

11. Don’t waste time doing unilateral movements, or cables, unless you’re already really built. Even then it might be a waste of time. The body is a bilaterally functioning machine – it works best when both sides work at the same time. If you’re trying to gain bulk or strength, stick to movements that involve both sides. Unilateral movements are much harder to control and to get a good muscle workout so maybe they’re for later when you’re more experienced. Maybe.

12. Leg abduction and adduction machines. Yes I do have a bit of a thing about these, and they might be useful in certain circumstances. The ladies like them and think they will change their thighs in some way. This is unlikely. The forces on the legs in normal life are way higher than any effort on one of these machines. Who have the most powerful hip abductor and adductor muscles? Sprinters. Most ladies won’t want that sort of development but it points to what’s needed to power up these muscle groups and it’s not those hip machines.

13. Don’t mess about with useless exercises. If you’re trying to gain, then one-arm exercises, leg extensions and cables should not be your main line. The biggest muscles in the body will have the biggest metabolic and anabolic effect. This means the chest, back, buttocks and thighs.

This doesn’t mean the other muscles aren’t important, just that they are secondary when you are trying to get big. So squats, leg presses, bench presses, dead lifts, dips and chins are your friends.

14. Listen to your body telling you what exercises are good

The legs and calves take a huge amount of force just carrying us about, going up and down steps, running here and there. You can’t push them without adding something on top of this day-to-day stress to make them grow. This means squats or leg presses.

Natural movements that use the body’s functional movements such as squatting, dipping, chinning, benching and curling are likely to be way more productive that any made-up exercise.

Well that’s that off my chest! Let me know what you think about the funny behaviours we all exhibit in the gym. All human life is here.