Snugging not shrugging… is a phrase I keep coming across recently since I started my shoulder courses. I keep hearing therapists using this to describe what should be happening to the shoulder during movement. Its the belief that we should not let our patients with painful shoulder issues shrug their shoulders when moving. Rather they should focus on snugging the humeral head onto the centre of the glenoid socket. It’s a nice catchy phrase, and I usually like catchy phrases, however, I think this one, is not a good one…
First, why are so many physios focused on telling patients what they can’t or shouldn’t do, rather than spending time finding out what they can do?
It seems perverse to me that patients usually come to see physios because they cant do something, only to have a physio identifying and telling them further things they shouldn’t do, such as stop shrugging a painful shoulder when they move it.
I dont actually think there’s anything wrong with a shoulder shrugging on movement, especially when someone has shoulder pain. I see it happening a lot. It’s a common compensation many use to avoid pain on elevation, and often it is a really effective one, so why would I or you want to stop it?
In fact shoulder shrugging is one of a group of symptom modification test I use with those with shoulder pain. I actually tell some patients to start shrugging their shoulders to get them moving more and with less pain!
Now, if shrugging becomes maladaptive once pain has ceased, then yes, that needs to be addressed, but in my experience rarely does this happen, most shrugging shoulders usually return to ‘normal’ once pain has eased, stiffness loosened, or strength has returned without any intervention or fuss.
But physios and Scapula’s are a strange mix, I see many over focus, over diagnose, and over treat them. Please can we just let Scapula’s be Scapula’s. Let them wiggle and wonder around a bit occasionally, there is little to no evidence that it causes any issues or does any harm!
What also concerns me about this phrase ‘snugging not shrugging’ is there is a belief by some therapists that the humeral head is and should be maintained on the centre of the glenoid at all times, and that they can assess when this is, or is not happening with clinical testing.
The way that many do this is with the Dynamic Rotatory Stability Test (DRST) and the Dynamic Relocation Test (DRT), first described by Mary Margarey in her 2003 paper here. The tests are described and shown in the photos below from the same paper.
As you can see, the DRST shows the examiner attempting to palpate the position of the humeral head in various positions to assess for excessive movement of it and that it is centered. In the DRT the examiner is palpating to ascertain if the rotator cuff is co-contracting equally without any ‘over-actvity’ of the superficial muscles of the Lats, Pecs during a distraction and subsquent snugging manoeuvre.
Now, I remember being taught these tests as a fresh faced, newly qualified physio many years ago, and I remember having the same incredulous, astonished thoughts and feelings about these tests as I had with the spine and SIJ palpation tests, which I describe in one of my first and most popular blogs here.
I just could NOT believe that anyone could actually feel anything close to what was expected. I couldn’t believe anyone could feel the humeral head moving an extra few millimetres under all the soft tissues of the shoulder, or even more unbelievably if it was centred on the glenoid or not. Nor did I believe that anyone could feel if the rotator cuff was contracting equally, quickly, or strongly enough, and if the Lats and Pecs were contracting too much, what is to much?
However, just as with the SIJ my skeptical feelings quickly turned into despair when I began to see and hear that in fact everyone else seemed to be able to do just that! Here we go again Meakins, I thought, you’re still a ham fisted, sausage fingered numpty. Here’s another bloody physio test you can’t do, you fumbling buffon.
But I persevered and kept trying with these tests for a while longer, but try as best as I could I just could not, and I still can not, feel if the humeral head is moving too excessively, or if its off centre, or if the cuff is not working enough, or the Lats/Pecs too much. In fact I can’t even feel the humeral head at all on a lot of people. Ok on the smaller, thinner people, you can, but most with half decent Deltoid muscle bulk its challegening to say the least.
So I have stopped using these tests, and if I’m being honest I forgot all about them, until recently when this ‘snugging not shrugging’ phrase kept popping up on my courses.
Now as far as I am aware, the DRST and DRT have not had any validity or reliability studies, nor any trials to assess their usefulness in the assessment and management of shoulder issues. And as far as I am aware (happy to be corrected thou) there are no specificity or sensitivity figures in their ability to detect these humeral head centring issues.
However, what I can comment on now I have a better understanding of the shoulder, is the premise of these tests is flawed. Firstly the cuff does NOT co-contract equally, and so trying to palpate this is not going to give any information of clinical relevance.
It is now pretty much widely accepted that the rotator cuff has a direction specific action. This has been shown in these intriguing EMG papers here and here and here. They show that during flexion movements the anterior cuff, eg the Subscapularis is pretty much inactive. Instead its the postero-superior cuff that is highly active as it draws the humeral head back and down against the up and forward forces created on it by the Deltoid muscle.
Secondly, the notion of assessing if the humeral head is centred on the glenoid is also flawed. The humeral head does NOT stay centered on the glenoid in normal pain free movement. There are a number of studies here and here that show the humeral head displaces off the anatomical centre of the glenoid in normal healthy pain free subjects. In fact some of these normal healthy pain free subjects have up to 12mm of humeral head displacement!
Finally this review here on the biomechanics of the glenohumeral joint describes that the rotator cuff and other sub acromial structures regularly come into contact with the acromial arch as the humeral head migrates superiorly during normal, healthy, pain free movement.
So I hope you can see that trying to assess if the humeral head is perfectly centred on the glenoid, is improbable, and unlikely to be happening, even in those without shoulder pain.
All shoulders that I do come across with humeral head ‘centring’ issues, are usually very easy to see and assess without the need of these ‘special’ tests. I do accept that attempting to assess and identify those with more subtle shoulder instability is challenging, but, im afraid tests like these dont help, instead we need to rely more on our subjective history, clinical expertise, experience as well as imaging.
So please can we stop telling patients to stop doing things, especially things that may actually be helping them, and that has no evidence its doing them any harm. Can we stop with these DRST or DRT tests, and with the illusion of being able to palpate subtle humeral head movements, or rotator cuff co-contractions. Lets remember we are in 2015, not 1995, and that we should have learnt by now that tests like these are just palpation pareidolia!
As always thanks for reading