Healthcare can be like a playground with its swings, roundabouts, and see-saws. Clinicians often swing from paradigm to paradigm, patients can feel like they’re on roundabouts going in circles, and all of us have felt the see-sawing highs and lows of trying to help people with pain and disability.
As a shoulder ‘specialist’ one area that I have had many highs and lows with over the years is sub-acromial shoulder pain. I find it both a fascinating yet infuriating condition, not only due to the difficulties in its diagnosis but also the uncertainty in how to manage it.
One uncertainty I have had for a long time is what role does surgery have, in particular, arthroscopic sub-acromial decompression surgery? Who is best suited for this operation which involves shaving the bone of the acromion and the removal of the sub-acromial bursa and sometimes the coracoacromial ligament which is believed to reduce compression of the rotator cuff underneath?
I have discussed some of my concerns and issues with this operation before, having seen it performed too often, too quickly, and seen too many patients worsen afterwards. But I have also seen some great success and some very satisfied patients with this surgery. So the questions are why do some do well and others not? Is it the surgery, the rest and rehab after, or maybe its something else?
To try and answer these questions a highly anticipated paper was published a few weeks ago in the Lancet called Can Shoulder Arthroscopy Work or CSAW. It’s free to access and I urge you all to read it as I believe it to be one of the most important papers on sub-acromial shoulder pain ever published.
This large, rigorously conducted, randomised controlled trial compared three groups of patients with sub-acromial shoulder pain. One group served as a waiting list control and were not given any treatment at all, only being followed up at 6 and 12 months using the Oxford Shoulder Score.
The other two groups had arthroscopic surgery on their shoulders. Half were randomly allocated to have a diagnostic arthroscopy which only involved placing the surgical instruments into their shoulders under anaesthetic and then removing them. The others had a routine arthroscopic decompression which involved shaving the acromion, +/- removal of the bursa and the coracoacromial ligament as deemed necessary by the surgeon.
All the patients and those involved in their follow up care were blinded so no-one knew who had just the arthroscopy or the decompression, and both groups had the same aftercare and physiotherapy treatment. They were also followed up at 6 and 12 months using the Oxford Shoulder Score outcome measure just like the control group.
The results below show that there is NO significant difference between the two surgical groups, demonstrating that shaving the acromion and/or removing the bursa and ligament is not needed to reduce sub-acromial shoulder pain and disability.
Essentially this demonstrates that arthroscopic sub-acromial decompression surgery is a placebo, and due to the costs and risks involved it strongly questions its continued use in the management of those with sub-acromial shoulder pain. However, there was a significant difference between the two surgical groups and the control group. This shows that something had an effect on the surgical groups, but if it’s not the shaving of the acromion or removal of the bursa/ligament, then what is it?
Physio, the new gold standard?
Well, it could be the effect of the physiotherapy and rehabilitation that was given to both surgical groups after. However, before we get too carried away and start to think physiotherapy is the new gold standard treatment for sub-acromial shoulder pain, we need to look a little more closely at the results and put our critical thinking caps on.
First, we need to remember that statically significant doesn’t automatically mean clinically meaningful. If you look closer at the results you will see that the difference between the waiting list control group and the surgical/rehab groups is small, really small, and the authours state that they’re uncertain if this difference is meaningful, as do I.
We also need to remember that control groups in research trials often suffer from the phenomenon of resentful demoralisation. This is when subjects who consent to a trial realise that they are not having any treatment and start to feel hard done by. This means they often report their symptoms are worse than they actually are, possibly meaning that this control group could be even better than they reported, further reducing the statistical difference!
Looking at these results we do have to ask ourselves is this just natural history and both the surgery and the physiotherapy are doing very little? So just as with the surgery the question we should ask is does the cost, time, and resources of the usual 6-12 physiotherapy sessions and multiple interventions used such as manual therapy, taping, and corrective exercises justify the small improvements and changes in outcome seen here?
Over treated, over complicated?
Now you might think I am being overly harsh and negative on physiotherapy yet again, but we have to put our practice under the same critical lens as we do with others. I am and always will be an advocate of physiotherapy and I do think we can be effective in helping those with sub-acromial shoulder pain. However, currently, I think many physios over complicate and over treat this condition doing some weird, wonderful, and wasteful stuff such as scapular setting, taping, needling, and not forgetting all that shoulder symptom modification procedure nonsense.
In my opinion, most with sub-acromial shoulder pain can be managed by being confidently and compassionately reassured that the pain they feel is nothing serious and that it will get better over time, but this will be longer than they expect or anticipate. They should also be advised to carry on as best as they can and not let the pain worry them that they are harming themselves, nor should it deter them from doing activities and of course be encouraged to do some exercise.
It would have been interesting to see what would have happened if there was another 4th group to the CSAW trial, one that was given the information and advice that I have just mentioned and given some general upper limb exercise. Would we have seen something like I have hypothesized below? Who knows, this is just my theory and bias, and maybe for the CSAW V 2.0.
So it looks like the end is nigh for the arthroscopic shoulder decompression operation after this CSAW trial… or does it? Well, let me give you an example of one patient I had with sub-acromial shoulder pain recently and show you how sometimes it isn’t as black or white as this.
Last year I had a 36-year-old, very keen recreational triathlete who regularly competes in ironmans come and see me about his chronic right shoulder pain he was feeling during his swimming. He reported no previous injuries but this shoulder pain had been slowly building on and off for about a year. It was becoming more pronounced and was now limiting his ability to swim, and he also noticed it on other activities during the day and at night when sleeping on it. He had no past medical history, he was fit and healthy, had low levels of stress, was in a job he enjoyed and had a happy family and social life.
He had already seen a specialist shoulder orthopaedic consultant privately and had an assessment and MRI. From this, he was told that he had no tears or splits of his rotator cuff and his ACJ and acromion was normal with no large spurs seen but he was recommended to have an arthroscopic decompression to give more space for his shoulder when swimming and reduce the pressure on his rotator cuff.
However, he had done some reading and knew that physio and exercise based rehab is also an option and he was not keen for surgery. During the history taking, I could tell he was well read on sub-acromial shoulder pain, and he had hopeful yet realistic expectations of physiotherapy which we know is a strong predictor of successful outcome.
My physical assessment of him was unremarkable, he had no gross loss of movement or asymmetry, he also had no sub-acromial or ACJ pain provocation signs. The only thing I could highlight was a 25% loss of external rotation and flexion strength on handheld dynamometry testing with no major pain felt. I was unable to elicit any signs of subscapularis issues or anterior internal impingement pain on testing which is now thought to be a factor in swimmers shoulder pain. This clearly was a high performing low irritable shoulder with no major structural or biomechanical deficits that I could see.
Based on this assessment we first got him to start recording his training keeping an accurate log of his swimming volume ensuring he kept his weekly volumes between 0.75-1.5 of the previous weeks. He also started working with a swimming coach to look at his technique and had some minor adjustments but was told there was nothing major amiss here.
I also got him to look at and address any other potential stressors at home and work, and we improved his recovery strategies mainly his erratic sleeping patterns and times. And finally, of course, I strengthened the shit out of him. I got him to do two 30-45 minute sessions of S&C a week which included two upper limb exercises performed over 3-5 sets, using high load (>60%RM) moderate reps (6-12) mainly focusing on his external rotators and posterior chain, which we changed every 4-6 weeks.
At the end of 6 months he was more organised, better focused, feeling fresher, faster, and stronger than ever before, but… he still had the same fucking shoulder pain when swimming. After some deliberation he decided to go ahead and have the arthroscopic shoulder decompression much to my disappointment.
He was well aware, thanks to my constant harping on about it, that this operation was not guaranteed to be successful. He was well aware that there are small but significant risks. He was aware he would be set back and would need to do all stuff we were currently doing all over again. Regardless he went for the decompression.
I next saw him 3 weeks after the operation which went without any issues. The surgeons’ report was unremarkable just a standard acromioplasty with no other significant pathology noted. He had already gone back swimming a few days ago to tentatively test it out and he reported an instant improvement in his shoulder already. He knew that this could all be placebo but he didn’t care, something felt better after the operation that wasn’t before despite our best evidence-based efforts.
This case just highlights to me that how despite knowing what we know, there is still a lot we don’t know. It also makes me wonder if the arthroscopic sub-acromial decompression surgery still does have a role in SOME patients who are FULLY informed of the risks and the uncertainty of what and how it works, whether this is ethical or not, well that’s another question best saved for another time.
As always, thanks for reading