Clinical Edge - 105. Scapular dyskinesis - Does it really matter? with Jo Gibson Clinical Edge - 105. Scapular dyskinesis - Does it really matter? with Jo Gibson

105. Scapular dyskinesis - Does it really matter? with Jo Gibson

CLICK HERE to download a PDF version of the transcript

Jo: We asked for some suggestions, we've got a long list of things that we'd like to share with you, but Darren was right in there asking about scapular dyskinesis. So, thank you Darren for that, and that's what we're going to talk about, the relevance or otherwise of scapular dyskinesis. That actually worked very well because I had a gentleman that I saw on a telehealth consultation the other day, who had, had physiotherapy before lockdown, had actually done fantastically well, got back to all the things that he wants to do, but was still concerned that he had this asymmetry in his scapula. He didn't have any pain, but his physiotherapists had said they couldn't help anymore, and so essentially, he was very concerned with this ongoing asymmetry. So, this guy was obsessed with the fact that he had what he perceived as this winging scapula, and despite the fact his pain was gone and he was back to doing everything that he wanted to do, he was still very worried about sorting this out.

Now it's important to say before we go any further that we're just talking about somebody with insidious onset shoulder pain, doesn't report anything that might be consistent with a true nerve injury that would give us true scapular winging. We're just talking about the scapular dyskinesis that we see in association with non-traumatic shoulder pain. Now, just to quickly mention, because again, I had a very interesting case. A climber who'd had an injury where he'd fallen off whilst doing a climb. He'd done an overreach and slipped, and so had gone to see a local physiotherapist. His injury was actually in his hand. It wasn't anything to do with his shoulder. The physiotherapist had done a very, what sounded like quite a deep massage, shall we say, around the shoulder. This guy came to me because he was very worried that he developed this mark winging and was struggling to lift his arm up. Now, when he came to see me, he actually had a spinal accessory nerve injury. So, the force of the massage had been sufficient to give him a transient neuropraxia.

Now spinal accessory nerve injuries are interesting. The most common reason is actually usually iatrogenic, so associated with surgery and commonly anything to do with head and neck surgery or any lymph node biopsies. It also can result from stabbing, any heavy blows. I've had police ladies who had very heavy body armor, and that gave them a spinal accessory nerve injury after a particularly heavy shift. It's also reported that we can get it after amorous love biting, but I'm not quite sure who did that research. The key thing was spinal accessory nerve is, it's often painful because of the load on the plexus. They often have a very droopy shoulder and you can most expose that winging by doing resisted external rotation. They can't achieve full elevation range, they're really limited.

That's quite different from long thoracic nerve. Now, those of you that joined us last week, we talked about Parsonage-Turner Syndrome, and certainly the long thoracic nerve is one of those nerves that can be affected by that pathology. It's different in that patients can generally get full range of movements. It doesn't have the same pain features that a spinal accessory nerve does, and generally, if patients get pain, it's usually secondary the fact that their scapula is just not moving normally in the long-term, but that's a true nerve injury. Again, long thoracic nerve injuries are often iatrogenic in terms of related to surgery. They can relate to trauma and there's definitely an association with viruses or post-vaccination.

But the other thing you'll see is slim ladies or anybody having axillary clearances or biopsies, if they're slim, have a real risk of a long thoracic nerve.

So, the other thing we see quite often is people who have obstetric or gynecological surgery and positioning, if they're slimy and they're actually on stretch. So again, when we're talking about that true winging with serratus winging, often you'll see it at rest and obviously it's most exposed by doing wall press or those serratus type tests. So, we're not talking about that tonight. We're just going to talk about scapular dyskinesis. Now, why do I think it's important? Well, one really this patient raised it because they obviously think it's important, despite the fact they've now not got any symptoms.

So, what are we going to talk about? Well, I think there's some common beliefs when it comes to the scapula. Firstly, that there's a link between abnormal scapular kinematics and pain. Secondly, poor old upper traps get maligned as the bad guy, and we get obsessed with differences in muscle recruitment. Thirdly, that scapular dyskinesis can help predict patients that are likely to develop shoulder pain. Fourthly, that scapular based interventions may have some superiority over our rotator cuffed ones. And finally, there's all sorts of fancy things we can do assessment wise. Well, let's have a little look at those. In term of the link of scapular kinematics and shoulder pain, it's really not well supported. Essentially, if I took a hundred people who'd never had shoulder pain, a hundred people with shoulder pain and put them all in a line and film their scapula, there would be an equal distribution of asymmetrical scapula. Asymmetry is very normal.

Actually, if you look at overhead athletes, about 61% of overhead athletes will have scapular dyskinesis or asymmetry in how their scapula moves. Actually, if you follow athletes over time, they'll often develop scapular dyskinesis as part of their adaptation and it's well-described that we get changes in range of movement in the shoulder. Well, again, we see changes in terms of the scapula. So, we have to be a little bit careful because if it's a normal finding, using a kind of, yes/no classification scale, we need to be very careful about making patients too vigilant about it. Now, before you panic and think the scapula has got nothing to do with it, us observing it, there are asymmetries in non-symptomatic populations. Now, if we take the patients with shoulder pain into a lab, and then we compare them to the people without pain, there are some key differences, both in terms of the ratios of muscles working and when those muscles work in range.

But also, if we use things like fancy 3D fluoroscopy, there are also some common themes in terms of a loss of upward rotation, protraction and posterior tilt. The challenge is, whilst those lab-based studies using very fancy kits or needle EMG can show those changes, we don't seem to be able to pick them up reliably in the clinic. Now again, if we look at scapular kinematics and what they're impacted by, there's no doubt if people have a very stiff shoulder, then they use their scapula differently and they get some of these typical compensation patterns, particularly with upper trapezius working because they can't access anything else. If you fatigue, there’s some nice studies by Ebar et al looking at somebody as scapular dyskinesis fatiguing their rotator cuff and showing that, that worsens their scapular dyskinesis. Similarly, people with massive rotator cuff tears, we see some common themes in how their scapula compensates.

So, it would seem that if we have significant pathology like a massive tear, if we have a nerve injury, if we have significant stiffness, or if we fatigue the rotator cuff, we can actually affect scapular dyskinesis. But the other thing that will cause it is a patient who's scared to move. So, we know in shoulder pain now, that some of the biggest predictors of outcome are in that psychosocial domain. And we've got studies showing us that if people are anxious or have a lot of fear avoidance or pain related worrying, especially with regard to a certain movement or lifting their arm up, that has an influence on muscle recruitment. They just preferentially use the big muscles around their shoulder as a kind of protect response and almost lose their normal weight transfer because they're trying to protect the shoulder. And of course, that could potentially relate in scapular dyskinesis. But the key is in terms of us clinically, we might observe that, but what's fundamental is addressing those fears rather than getting hung up on that scapular dyskinesis.

Now, I mentioned about this belief that upper traps are the bad guy and if you've joined us before we did a whole session, just looking at this. The bottom line is, there's a massive variation in people with pain compared to an asymptomatic population. People in pain move differently. Your central nervous system is very clever and finds a strategy to allow you to keep moving. Now, the bottom line with upper fibres of trapezius, if you think back to those examples I gave you before, that seemed to result in scapular dyskinesis, i.e., stiffness, significant cuff tear, nerve involvement, and actually cervical spine involvement as well. Actually, if we look back to the studies, if I'm stiff, I use it because I can't use anything else. If I've got a massive cuff tear I use it because I can't use anything else to get that movement initiated. And in somebody with neck driven shoulder pain, then upper traps may be truly a little bit dominant at the beginning because it's segmentally facilitated and again, it's a protective strategy.

But actually, if we look at patients with shoulder pain and we look at the studies that described this overactivity in upper fibres of trapezius, that actually formed the basis of a lots of people trying to switch it off. Actually, it was only overactive the later degrees of elevation. So, if you like, it was more common for it to be weak. And so, people would move and then it was trying to play catch up at a mechanical disadvantage. So, whilst we have needle EMG, studies showing us there were changes in the ratio of activation, there's a massive heterogeneity across all populations and so really, it's about just making sure we address some of their fears about movements and use some simple strategies to improve their shoulder function.

Now, we also said that the general belief that scapular dyskinesis is predictive of pathology. And there was certainly a study by Hickey et al that suggested that if you had scapular dyskinesis, you were 43% more likely to develop shoulder pain in the subsequent season. And I think if we're honest and we go back to the statistics in that study, actually it wasn't quite that dramatic. The relative risk was actually much smaller than that. What's interesting, there are a few studies that show if you just use a, yes/no score at the beginning of a season, then if you have a massive change in load, that may give you a slight increased risk of developing shoulder pain, however, it's negligible in some studies. What seems to be more significant is change. So, if you did a yes/no score at the beginning of the season, and then you film them again, let's say three months down the line. And there was a significant worsening, that change may have more relevance than just using it as a standalone measure at the beginning of the season.

And I think in that situation, we have to be honest the jury is out. So, last two things were about scapular-based interventions and also about assessments. So scapular-based interventions, is there any superiority? What is clear in the shoulder? The good news is as somebody who supposedly works as shoulder specialist, the evidence supports that doing shoulder specific exercise is preferential to general exercise. There is a systematic review of scapular-based interventions that suggested about six weeks. They may have some preference to general shoulder exercise, but actually after that period, it's not born out. As long as you're doing something to the shoulder, then both approaches work. What I would say to you is, when it's a scapular exercise, not a cuff exercise.

If you look at the attachments of the rotator cuff onto the scapula, we can't differentiate these two things. And unless we had a nerve injury where we have to target a particular muscle to get it stronger, why would we want to? Because that system functions together.

When we look at our scapular-based interventions, what's interesting is there is evidence that we change ratios of muscle, but that doesn't have to correlate with changing what we observe in terms of that scapular dyskinesis and interestingly patients get better in terms of their pain and their function and yet that doesn't correlate with an observable change in that dyskinesis. I think if you talk to a lot of the people who work in sport, I was lucky enough to lecture with Martin Asker on a virtual conference the other day. And he was saying that having once upon a time being an absolute scapula obsessive, he now just accepts that it's part of the wondrous spectrum of how people move. So, the good news is, you don't seem to have to change scapular kinematics from our simple, yes/no looking at that asymmetry to be able to change pain and function in people with shoulder pain.

So, where does that leave us, is there any point assessing the scapula? Well, there's been some great questions about the different classification systems. Currently, there are 41 different assessment procedures described for assessing the scapula. Only 12% of them have any intertester reliability. And that 12% are the static measures. So, if you'd like somebody with their arms, by their side, somebody with their arms here, maybe up in range and measuring from the spine to the scapula or using our iPhone, some of these digital goniometers or balance measures. But the bottom line is the static measures have now been shown to have no correlation whatsoever with what happens when we move. So, you can look pretty pants at the start, but actually you could move really well or recruit your system very effectively. That's why symptom modification in terms of the scapular-assistance test has become very, very popular. Because essentially, it's based on those original studies that suggested there was a theme of a loss of upward rotation, a loss of posterior tilt. So, if we passively did that and changed somebody's pain, it was very much believed that that then meant they should do scapular exercises.

Now, couple of things we need to be careful about. In terms of scapular-assistance test, there was a study looking at 3D MRI that actually showed it did increase the size of the subacromial space, but with some recent research, it's less clear how relevant that is. And actually, it's probably more to do with the size of what's in that space. However, there's no doubt it did improve upward rotation and protraction. However, the other thing, when we put our hands on some of these scapula and then re-assess the effect it has on their movement, we're also unloading that upper quadrant. So, we're making it easier for the shoulder to do its job. So, I think we have to be a little bit careful in terms of the interpretation.

What's interesting is, if we look at prognostic studies that clearly show that most of our prognostic factors in shoulder pain in that psychosocial domain or associated with lifestyle factors, apart from the amount of pain and disability somebody has when they first present. The only physical predictor of outcome in Rachel Chester's work was the scapular-assistance test. So essentially, if you're able to change somebody's symptoms, the first time you met them, you could be more confident they were going to respond to rehabilitation. Now, of course, there's lots of other things like self-efficacy, the length of time they've had their pain, all those other things that we've mentioned. But interestingly, the scapular-assistance test did seem to have some predictive value. There's a surgeon called John Kuhn who's based in the States, who did a similar thing that he presented at the Scapular Summit a few years ago. And he also showed in over 550 patients with non-traumatic rotator cuff tears, that if you could change their symptoms with a scapular-assistance test, the first time you met them, then they had an 80 to 85 chance of getting better with rehab.

Now it doesn't mean we have to be able to change it. However, what I would challenge is if I do a scapular-assistance test, it means I have to do scapular-based exercises. I don't, I need to exercise the cuff and the scapulars together. Now for me, if I can change somebody's pain, that's great. It probably identifies a responder. And all it means to me is I'm going to probably emphasise the scapula as part of their cuff and scapular exercise. So, if we look Ann Cool's lovely work, just doing short lever, external rotation against a resistance, it seems to be a great way of normalising those ratios, which has been a big basis of Ann's work and actually just get to the cuff and the scapular muscles doing their job. And if they can do that, maybe I'd just put a band around their back to reinforce that scapula and give them some feedback, or I could do it with a ball behind them on the wall and do it like a wall squat. All I'm looking is something that replicates what changes the patient's pain.

I don't think it means that we do scapular-based exercise. Now in terms of assessment, where does that leave us? Well, guys, I'm afraid that yes/no is about as good as it gets.

Let me just get on these questions. One of them was about, can we use these classification systems? So, Ben Kibler described the type one, two and three, and I actually did a fellowship with Ben Kibler way back in 1995 I think, with Ben Kibler and Tim Uhl and I spent a couple of weeks out in Kentucky and then went back to the Scapular Summit. The sad reality is that if you look at the intertester reliability of the type one, two, and three classification system, it's actually very, very poor. And remember, again, it's very, very subjective. The type one, two and three, waste of your time, yes/no is as good as it gets and how relevant it is in any way.

For me, if I've got somebody doing a loaded exercise, I'd quite like that scapula to be congruent because I think that correlates with transfer of load. So, no Lee, there is no reliability in scapular assessment. It's not a good investment of your time. And I would say symptom mode, just the scapular assistance as a symptom modification may give you some value. So, Adam, I think what you highlight there is very important in terms of identifier responders. So yes, there's no doubt, it's potentially a group that are more likely to get better. I think it's really important for me to be honest, that the majority of patients I see are three, four years down the line. So natural history hasn't done its job, they've failed. And yet in those patients, I can still affect the change with scapular assistance.

I'm not claiming any biomechanical effects, all I'm doing is something that's unloading that shoulder. So, you could argue, it's just replicating, what we already know is I need to unload things or as Greg would say, "Calm shit down to then build it up again or unload to reload." So, for me, it's a small part of my assessment.

But if I've got somebody who's very reluctant to move, it can just be part of, if you like the symptom modification I'd achieve with my education, my validation, my reframing of their pain to get them move. So, I'm not claiming any magic effects, but again, as you know, I like a symptom modification approach because I think it's one way of approaching some of those negative descending influences. If I can change somebody's movement experience and change their pain immediately, I didn't say I'm going to change their pain. I just go through some stuff and they go, "Oh, that feels easier to move." That we know from the pain sciences has a massive modulating effect on some of those descending influences both in terms of that expectancy violation and predictive processing. So, I do think it has a role.

So, I don't use sweet types of dyskinesia, guys we can't stratify them. It has no meaning in our treatments. Winging post-surgery, as you'll remember. I said at the outset, when we look at true scapular winging, actually a lot of long thoracic and certainly spinal accessory stuff is surgically based. However, after stabilisation surgery, one of the most common nerves that gets damaged is the axillary nerve. And we did a thing about that a couple of weeks ago on Facebook Live. So, winging post-surgery, posterior stabilisation and label repair. I'd want to check that I haven't got any evidence of clear muscle weakness. You'd want to check out your cuff in terms of suprascapular nerve, because they've had a posterior stabilisation, but also that axillary nerve and particularly the posterior branch. So, look at your teres minor and your posterior cuff.

If they haven't got any true weakness, remember stiffness will drive scapular winging as a compensation, they're just trying to find a way to move. And in terms for me, I just always like to do some sort of short lever through range posterior cuff work, just to get that system engaged for a foundation of load if it's appropriate. So, in answer to your question about a post-op patient, I think if you look at the limited evidence we have about the influence of restriction, you kind of need around 70% of your rotational range when you're doing stuff above head. So, an often what you'll find with your posterior stabilisation is actually where they get stiff is at the back of the joint in this posterior, superior complex. So that's looking at internal rotation in neutral. So, it's worth having a look at that.

So again, I'd be looking, is it stiff? Because remember that can be a driver. Have I got weakness? Has there been some sort of nerve involvement? So just have a close look at the two most commonly involved nerves, which is the axillary in the suprascapular with that particular group. The other thing that I do, do is, I really emphasise the inclusion of the kinetic chain early in rehab, purely because we've got some evidence that it just has a preferential effect on local scapular recruitment. And it just makes it easier for the patient where maybe they're a bit apprehensive or there are things that are making them difficult for them to move.

Q: In terms of patterning, any effective ideas on switching off scapular muscles in patterning? I have to say I'm probably a person who's been guilty of using the word muscle patterning. I have seen probably a person who's been guilty of using the word muscle patterning and we used it really to try and validate a group of patients that had been written off as having voluntary instability. What we're finding now in our research is it relates very highly to pain beliefs and negative psychosocial factors.

So, we did some FMRI work, we looked at patients who failed our rehabilitation in terms of general rehabilitation and all sorts of fancy things to try and get them better. And when we actually did FMRI of their brains, we found that all their movement processing was through the movement centers of their brain. So, it kind of brought us full circle. So, it's not a copout. It's really important that the most important thing we need to do is actually address a patient's fear beliefs. Because if we don't do that with the best will in the world, there was some lovely work by Paul Hodges and Lorimer Moseley many years ago that showed that people who had negative pain beliefs, even when their pain had gone away completely, continue to move with those compensatory strategies.

Random question, are there any studies looking at weight loss on scapular function, overweight patients, pain and non-painful who seems to have really poor scapula. All I know is slim people who have any sort of axillary surgery or any surgery where their arms on stretch, you're more likely to get a nerve injury, but in terms of looking at weight loss and scapular function, I can't answer that one. That's a brilliant one. You've definitely stumped me there. And I should be looking that up and seeing if I can find anything.

Bruno, how hard do you find changing fear of movement in patients with a long history of pain, do you have a secret trick? My secret trick is solicit and understand the basis of those beliefs. So, I think... We talk about symptom modification.

Some people like it, some people don't. For me, it's just a potential tool in challenging some of those pain beliefs. It's very empowering to somebody to see that actually something that they've lived with for a long period of time, we can suddenly change. And if you ask what my typical approach to symptom modification is, in my head, I just think I'm going to unload. I might give them some resistance to just change their movement strategy. And I might incorporate the kinetic chain because I think we have some tentative evidence that it kind of makes life easier for the shoulder. But again, I'm basing that on my understanding of muscle function and what goes wrong in shoulder pain, but also acknowledging that there's probably lots of different mechanisms and it could just be my reassurance, it could be distraction, but fundamentally I'm trying to unload as a basis for them building that patient back up again.

But listening and understanding, asking patients what they've been told about their shoulder pain, but then importantly, asking them what that means to them. Because actually a lot of the time, the things that are stopping people move without pain are purely because they've adopted these protective strategies. So, from my point of view, my tricks are those symptom modification. Very, very simple, literally three or four things that seem to have good value in the clinic. And if they're going to work, great, if they don't, I'll probably have a good impression about anyway from hearing the patient's story. So, invest in listening and understanding the individual, and don't be afraid to challenge those beliefs. Remember if somebody comes with really high levels of pain and disability and they don't have a history of a pathology that's consistent with that.

So, who comes with the horrible levels of pain? So many with horrible radiculopathy, somebody with a developing frozen shoulder, somebody with an acute calcific tendonitis or tendinopathy and somebody maybe with a reactive tendinopathy. If they don't have a history consistent with those things, they've just got insidious onset pain and horrible levels of pain and very reluctant to move. You're going to invest in that story and understanding what's driving those fears.

What do I think about the scapular dyskinesis test? I think for me, the only thing I really do in terms of the scapula, is that scapular-assistance test as part of my symptom modification. And as I say, I think it's a loading test. When I was with Ben Kibler, they have their scapular retraction test where again, they might do their cuff testing, but then do a scapular retraction and hold it in place and see if they're stronger. Again, I think we just have to be honest that we don't entirely understand what the mechanisms are. To me, if I unload somebody's shoulder, it makes it easier to move. Then I'm just going to replicate that in my exercise prescription.

But I think the other thing we mustn't underestimate is that, if patients have an exercise that they perceive as meaningful to them, based on something that changed their pain, then the adherence literature would suggest they're more likely to do it. So, let's say I did a scapular assistance, it made that pain better. Then I'm just going to replicate it as I said that before, whether it would be with a band behind their back, leaning against the wall, something behind them, because then they know, or they perceive they have an exercise that basically is based on their particular problem and they then feel more confident to move. And then we can use those same things into strategies to translate into their function.

What I would really say is that standing and believe me, I've invested a lot of money in a lot of courses over the years, learning how to assess the minutiae of scapula, so now to realise that it probably didn't have much basis is kind of slightly irksome, but actually quite empowering because it means we don't... But what is also massively important, is we don't make our patients vigilant.

Remember, I said from the outset, the guy that really got me wanting to talk about this, and then Darren kind of suggested it as a subject, was this guy was really vigilant about that scapular asymmetry, it was pretty mild and he had no pain, full function and was back at the gym, doing everything that you wanted, but because the poor physio he met in the first time, had really pointed this out and said it was stopping his muscles, doing their job properly. That was a massive block to his belief of how well he'd done. So, guess what? We did a lot of talking.

So, the question... When Chris Littlewood and Filip Struyf was on Adam's podcast. Filip talks about two expected studies on high level athletes. And in those days, they saw an association with injury or was it pain? So yeah, it was and so there is a mild increased association with a mild increased risk of developing interest in some studies, but it's not been born out. So Clarsen et al did a study, Anderson looked at it as well. And essentially there was one study that said, "Yes, scapular dyskinesis was predictive." When they then looked at longer term follow-up in more athletes, they weren't able to bore out those results. And Chris Littlewood actually did the fantastic response to the Hickey Article, actually breaking down the statistics. And again, showed there may be an increased association with a risk of developing shoulder pain. But I think we have to be careful saying it's causative. What I would say, and what I find useful in the athletes I work with is change.

So, if it worsens, that to me is more predictive than it is a standalone measure. Do I believe in a scapulothoracic bursa? They exist, we can see them in anatomical and cadaver studies. Does he remove them? There was a trend many years ago, a diagnosis, I think they used to call it Snapping Scapula, which they thought was due to this thickened bursa. And in fact, many, many years ago, they used to actually excise the superior medial border of the scapula. I'm delighted to say they don't do that anymore, or very, very rarely, certainly not in the U.K. One of our surgeons used to do that. And I remember looking at him saying, "But they've always had that bit of bone there. They've got no evidence that it's thickened. Why on earth are you going to take it away? Can we please try and do some physio and then see what happens?" So, we rehab them, none of them had surgery.

So, the bursa, are they relevant? I think we've had two patients in my entire shoulder career that have had injections into the subscapular bursa. And I think it's fair to say it works in one, it didn't in the other, and I'm not sure that it wasn't a placebo response. So, it's not something I would spend a lot of time worrying about. There are very rare bunch. Len obviously sees a very specific cohort and sees a lot of tertiary referral patients as we do. But I think it's something we went through a phase of doing, but we don't do anymore.

Adam made a very important point and I would really point you to that Chris Littlewood response to the Hickey article about the predictive value of scapular dyskinesis, because he did a lovely breakdown of all the statistics. The bottom line guys is, don't spend loads and loads of time assessing the scapula. Yes/no, it looks a bit wobbly as it's exciting as it can get. Symptom modification is more about changing pain than worrying about the scapula. Some patients will get dramatic improvement in scapular positioning, but remember a lot of them won't and it doesn't matter because that doesn't correlate with whether they get better or not.

Guys, thanks for joining. I hope I've shared loads of useful information with you as ever. We try and post some links afterwards. So, I'll post links to some of those studies that I've mentioned. So, you can read them for yourself and make your own conclusions. Filip Struyf has some great work as have some other authors looking at the relevance of this in our practice. So, I certainly signpost those for some more reading. Thanks so much for joining us. It was great to have some very big shoulder names there tonight and lots of my friends. So, thanks so much for giving up your time. Bye for now.

Are you ready to take your clinical outcomes to a new level?

Start your 7 day trial