Hi everybody. My name is Jo Gibson and I'm a Clinical Physiotherapy Specialist working at the Liverpool Upper Limb Unit in Liverpool, in the UK. Now if you've joined us on these Facebook Lives before, you'll know that this is part of a series looking at diagnosis of shoulder pain and tonight we're going to specifically look at talking about thoracic outlet syndrome. If you haven't actually seen our free videos yet, that series of three webinars, looking at the diagnosis of acute onset shoulder pain, then you can still access those at www.clinicaledge.co/shoulder. So, don't miss out because there's tons of information and lots of helpful hints that will help you in your everyday practice.
Now, over the years I've been lucky enough to work at the Liverpool Upper Limb Unit where we're recognised as a tertiary referral service and there's no doubt that we've had patients over the years which based on what I'd been taught as part of my musculoskeletal training, fitted the criteria for thoracic outlet syndrome.
I particularly remember a young guy that I met when he was in his teens. He was a swimmer who had symptoms of heaviness in his arm radiating paraesthesia, feelings of loss of dexterity in his hand, and he'd had a very frustrating time going backwards and forwards having various investigations. He'd had MR scans looking at his nerves, he'd had nerve conduction studies which were reported as normal and all in all, he'd had a very frustrating time and his mum was clearly very distressed because he wasn't able to continue with his swimming. Now at that time, when I look back, I kind of feel there's also those patients that stay in your mind that you feel that perhaps you didn't do the best job that you could. I did everything I thought I could do, I've got every investigation done that I thought we should get done, but everything came back normal and so then I was left really with nowhere to go. Now, this guy came back to see me a few years later and through one reason and another had ended up seeing a vascular surgeon. We'd done Dopplers, we'd done MRs in elevation views, but I think what we really need to do tonight is look at the different types of thoracic outlet. I'm going to primarily talk about neurogenic thoracic outlet tonight but I was very, very privileged a few years ago at the British Elbow and Shoulder Society Conference to meet a guy called Rob Patterson who set up the Thoracic Outlet Syndrome Center of Excellence. This guy's amazing and he's really trying to increase awareness and also ran a fantastic masterclass study day that I was lucky to attend recently. Now what he really highlighted for me is the need for awareness, the need for a consensus in terms of the terminology we use. But also, for those of you that I'm sure like me were frustrated when you think somebody meets those criteria, but then the investigations don't tie in or support your hypothesis, where does that leave us and what do we do next?
Because I certainly think in my experience, patients get written off as being difficult. Now when we talk about thoracic outlet syndrome, essentially, we're just talking about compression of one part of that neurovascular bundle whether it be the brachial plexus, the subclavian vein, the subclavian artery within that thoracic outlet. Now there's been a great consensus document done by the Vascular College of Surgeons in the United States and they stipulate that we should identify three key causes of thoracic outlet syndrome. So that's the neurogenic type that we're going to talk about tonight because it's by far the most common, the venous type and the arterial type.
So, the neurogenic type most commonly involves compression of the brachial plexus in that scalenii triangle area, the floor between the first rib and the anterior and middle scalenii. But also, we can also get compression behind pec minor in the retropectoral space and in fact, one of the interesting facts that came out from the masterclass is that between two thirds and three quarters of people with a neurogenic thoracic outlet syndrome can actually have double crush root compression at both those areas. The venous thoracic outlet syndrome obviously is going to be at the subclavian vein and that's generally at the junction of the first rib in the clavicle.
And interestingly arterial, which is by far the least common generally relates to objective damage of the subclavian artery, nearly always relating to abnormal bony damage. So, three very distinct groups. Now, about 6% of patients with neurogenic thoracic outlet syndrome can have a venous component to their problems, so it can be a combination. But tonight, we're going to concentrate on that neurogenic population, the 80% of that thoracic outlet population.
Now in terms of instance, again, there are some fantastic figures at the masterclass. They reported that on average there's about 10 cases of neurogenic thoracic outlet per hundred thousand people per year. Now, so if you think if you're working in a national health service or in a hospital that serves a population of about a million, then that essentially equates to 110 cases of neurogenic thoracic outlet every year. Now that might not be particularly meaningful, but when you think that actually that means it's as prevalent as something like Crohn’s disease and is twice as common as things like cervical, ovarian and thyroid cancer, it's something we need to be very aware of. It definitely seems to be more prevalent in women so 71% of cases are female and there also seems to be an association with hypermobility. So, 24% of patients with neurogenic thoracic outlet do seem to have some associated hypermobility issue or it sits somewhere on that hypermobility spectrum.
So, you can imagine for us in an upper limb unit, we see a lot of patients with instability and symptoms relating to that hypermobility issue. Now, when I went to the masterclass, I sat and listened to a patient, Lisa, who really kind of made me fill up and feel really quite emotional because she illustrated what I see for a lot of the patients that I've met who have finally been diagnosed with thoracic outlet over the years, and that was huge, she's had something like eight operations, she'd had so much conflicting information, it was significantly effecting her life. And she used some very powerful words in terms of living with undiagnosed thoracic outlet is like a life sentence. She was a sculptor, she was a plastic surgeon, she showed these really graphic pictures where she'd lost muscle bulk, she had significant atrophy with very dilated veins in her hands and she'd had years and years and years of intervention. She's had carpal tunnel releases, she'd had all the nerve releases and so this story went on.
And when you look and consider that the mean duration that patients have symptoms before they get diagnosed is 60 months, that's five years, that's phenomenal. And on average, these patients would have seen six doctors before they actually get a diagnosis. But there's no doubt there's a lot of people out there that actually don't ever get the diagnosis and are living unnecessary with symptomology. Now to try and address this and because of all this confusion and a lack of consensus, as I say, the United States Society of Vascular Surgeons formed a consensus group where they put together some key criteria and they now basically define thoracic outlet that it must have three out of the four criteria.
So, the first is hand and arm symptoms that are consistent with nerve compression and that those symptoms are often worse with activities, either overhead or with the arms dangling. So important things to ask patients in terms of their subjective history. In terms of where those arm and hand symptoms may be, then well, there's no doubt they can actually refer into their head, into the face, into the upper back, into the scapular region, the shoulder girdle, the anterior clavicle. They can refer into the chest, the axilla, the shoulders and actually certainly the patients we've seen in the upper limb units are patients that often have had two or three surgical procedures for shoulder and scapular pain, but also have referred symptoms further down into the arm and unsurprisingly that surgery hasn't been successful. So those symptoms are really important. They often describe heaviness as well, but again, looking at the activities that specifically aggravate those symptoms is clearly another important part of decision making.
The second criteria are pain and tenderness, potentially with associated reproduction of a patient's symptoms with palpation over either the scalenii triangle or that pectoralis minor insertion. So localised tenderness in one of those two areas, but also potentially with reproduction of their symptoms. Local tenderness can be sufficient, but sustained palpation may well reproduce their symptoms. So, you've already got two things. The third is absence of another diagnosis and this is probably where it gets challenging. The problem is there's been so many advances in pain sciences these days, it can be very easy to try and explain people's symptoms away in terms of central sensitisation when we can't put a label on it.
Certainly, cervical nerve root pathology would be one of our big suspicions and also peripheral nerve entrapments so again, we need to look at how we can rule in or rule out those specific diagnosis. In somebody with cervical nerve root compression we'd expect a more specific dermatomal and myotomal presentation with associated findings in the cervical spine and certainly supportive imaging. And this is where things can get quite challenging. And we're going talk about imaging and investigation a little bit more in just one moment.
So, so far, we've got the hand and arm symptoms that are consistent with nerve compression, we've got the pain and tenderness in the scalenii triangle and or the pectoralis minor insertion or that retropectoral space and we've got the absence of another diagnosis.
And the fourth criteria is a positive response to a scalenii block or injection. Now that might not be available to all of us. We're lucky that we've got that and got reasonably easy access to that where I work, but as I say, that is now defined as one of those four criteria stipulated by the College of Vascular Surgeons that are essentially in the workup and standards of reporting in this patient group.
Now there's some other things that can actually help guide our intervention. There's a questionnaire that I actually hadn't heard about before, which is called the Cervical Brachial Symptoms Questionnaire and that can help you actually differentiate between cervical causes of arm symptoms and thoracic outlet. And I'll post the links to some of the key articles at the end of this podcast. I'll signpost you to those reporting standards, I'll signpost you to the Thoracic Outlet Syndrome Center of Excellence and I'll also signpost you to that questionnaire. All very useful resources.
Now, one of the big issues and one of the big challenges I had earlier is that I'd send these people for investigations for MRI, for MR neurography that's supposed to specifically look at the nerves, and also for nerve conduction studies and got horribly frustrated when all these things came back normal, particularly the nerve conduction studies and I couldn't really understand why. Well this is where research is so fantastically helpful.
So, Anna Schmid's done some absolutely fantastic work in patients with carpal tunnel syndrome and actually looked at taking skin biopsies and looking at what that tells us about the nerves and looks at degeneration within that nerve. What her research showed very clearly is that actually the degeneration due to compression from carpal tunnel actually selectively affected the small fibres within that nerve. And you're thinking, “Well, thanks very much Jo, what does that mean?” Well, what that means is that nerve conduction studies pick up conduction in the large fibres of the nerve. Your small fibres are more to do with thermal detection and nociception. So, you can imagine that nerve conduction studies been normal actually doesn't tell us anything about those small fibres. The good news is there's some very simple clinical tests that we can use to actually look at that to try and detect small fibre degeneration and rule in a neurogenic cause.
So, there's a very fancy tool called the Quantitative Sensory Testing Protocol which encompasses all sorts of complex and expensive equipment. But the good news is there's some very simple things you can use in your clinic. You need to look at two key things according to the guidelines and according to Rob Patterson's fantastic resources and essentially, we need to look at pin prick in terms of light touch and we can do that using a Neurotip, which is available to most of us if we work in a hospital, but also looking at thermal detection, both cold and warm. Now, as I say in the quantitative sensory testing, they use a very fancy thing to measure this, but actually Anna Schmid's group so a lovely paper by Wright et al which I'll also post the link to, shows us that just using a coin and comparing their affected area with another part on the arm actually is a very sensitive way of measuring cold and warm detection.
So, you do it first with a coin at room temperature, which tends to be perceived as cold and then you put the coin in your pocket for 30 minutes, get it warm and then do the same test again. And actually, these things have been shown to have some really good value clinically. If you look at warm and cold detection thresholds, if they're normal, then you can be pretty damn confident that you haven't got any small fibre degeneration. If, however you've got reduction in pin prick, again, you can be pretty confident that you have got small fibre degeneration. The issue with pin prick being normal is it doesn't necessarily rule it out and that's why having the two ways of assessing is really, really important. And as I say, what's so great about those two very simple things is they actually have good reliability with more expensive tests.
Now the other thing in terms of our examination, of course we're going to do a full neurological examination on the entire upper limb. We're going to look for wasting, we're going to look at reflexes, we're going to look at sensation, we're going to look at pin prick in that thermal detection, but what other tests give us good value? Well again, in those reporting guidelines, they stipulate two key tests. One is the elevated arm EAST test or it's sometimes referred to I think in the text as a Roos test. Now this has been reported to be 90% sensitive, but again, if you look at the literature, there's some incongruity in how it's described and how to make it the most reliable. It involves having both arms in the surrender position, so this 90, 90 position and then opening and closing the hands for a period of up to three minutes looking for reproduction of symptoms, looking for changes of color in the limb.
But the thing that's really important about this is the timing and the positioning. One is having them absolutely up in that surrender position, but actually also having them in slight extension. So, we really are kind of putting stress on that thoracic outlet region. So, you can imagine if you let the patient drop their arms down or you let them start to drift forward, then potentially you could have a false negative with that test.
Now interestingly, there was a study by Roberts et al that showed that the average time or the mean time to onset of those symptoms was about one minute and 42 seconds. So that's a long time and again, when perhaps I talk to my colleagues, perhaps we just don't do it for long enough to get true value from that test. Now it's been reported as being 90% sensitive and again it figures in those reporting standards.
The other test, interestingly that again is very simple, is our upper limb tension test. So again, they described doing bilateral shoulder abduction with the arms extended and then extending the wrist on both sides and then tilting the head one way and then the other and then seeing if it reproduces symptomology. Now Rob's figures suggest that this is positive and about 80% of patients.
But again, it's very important to see and again I would signpost you to add some of Anna Schmid's work, again, I'll try and post the link for you, is that having a negative upper limb tension test doesn't rule it out, particularly in patients who've had symptoms for a long, long period of time where it would appear that upper limb tension test becomes less sensitive or less positive over time. So, you can see that actually with using those reporting standards, having those key four criteria, a very thorough neurological exam, those associated objective examination findings, actually there's an awful lot from this evidence and from these experts that are trying to increase awareness to really help guide our clinical practice.
So, as I say, I will signpost you to those reporting standards because they're absolutely key. But again, I would say that measuring that small fibre degeneration in terms of thermal detection is absolutely crucial. Some very exciting research that Rob's doing with Anna Schmid's is suggesting that there may be some change in cold detection in this group with thoracic outlets. But I think in the instance that thorough neuro examination, using other measures to look at that gamut of things cause really, we need to be confident we can rule out those peripheral nerve entrapments in terms of following a true nerve cause and having associated to special tests in terms of our Tinel’s and our Phalen’s, in terms of our cervical nerve root compression. We know that our Spurling's local palpation of the cervical spine and symptoms consistent with that nerve root, particularly if we have supportive imaging are extremely reliable in terms of ruling those things in as cause of symptoms.
If we don't have that and particularly if we have patients with a history of trauma or we have a history of repeated overhead use or any kind of mechanism that ties in with compromise of the thoracic outlet, hypertrophy of scalenii, trauma that we may have got some developments of fibrous bands or scarring, lots of potential mechanisms, but again, listing those symptoms is key. The majority of patients I've seen heaviness of the limbs is a common feature. Paraesthesia and numbness and sometimes changes in color have also been associated, but doing a very thorough neuro examination is absolutely crucial. But I think using the questionnaire can increase your confidence and as I say, using the particular information within those criteria and the reporting standards actually gives you some additional benefits as well.
Now where does that leave you in terms of investigations? The nerve block is not infallible. I think again, Rob's figures suggest that it's positive in about 80% of the people that he sees, and I think it probably is most positive if you do it under ultrasound guidance. And they would suggest doing it separately into those two areas if they're both tender, so doing the EAST test, doing your block, then giving it time to work, repeating the EAST test if that hasn't worked, then doing it in the pec minor region and the same thing. The question is if we find all these things, how do we decide who we need to refer on and who we should try physiotherapy with? Again, you can imagine that if these patients have had symptoms for years and years and years, the huge problem is that we're not now just dealing with something that may have been relatively easy to sort out where you're kind of looking at modification in terms of movements and posture and strengthening up the upper quadrant.
Certainly, there's been papers suggesting the efficacy of interventions that target upper fibres of trapezius, but how do we know which patients to refer on and who should we refer them on to? Well, that's not without its challenges. There's no doubt that if you pick up any evidence of nerve function compromise as part of your assessment, then the recommendations from the experts is you need early referral to a surgeon.
The problem is that most of the guidelines say that all patients with thoracic outlet should have physiotherapy as a first line treatment. Now again, having attended the masterclass and hearing Rob talk, I would challenge that and say that actually if you have somebody that you can demonstrate some changes in those small fibres and particularly if you have anybody with more gross changes in terms of the nerve system, then you need to get an early surgical opinion because that's likely to give them the best chance of a good outcome.
Again, because of the delay in diagnosis, when you look at the outcomes of thoracic outlet surgery, you can be fairly confident it will improve their core symptoms in terms of their arm and referred symptoms, but it's not always quite so reliable in terms of addressing the head and neck and back pain. So again, early referral and early suspicion of this is very important and I think that nerve involvement is really the key. Who do you refer them to?
Well, again, those reporting standards have been compiled by the vascular surgeons and certainly they seem to be the group that have most interest in this condition at the current time. I know within the British Elbow and Shoulder Society there's a couple of surgeons with a specific interest, but I think again, having attended the masterclass, what seems really key is to try and build links with people who have a high volume of these patients. They're relatively rare, but you need somebody who understands the condition, who's going to understand the limitations of some of our testing, like nerve conduction studies and MR neurography and actually appreciate the importance of considering all those different criteria.
Now a couple of you actually posted some questions early on the Facebook page and I just want to make sure. So, Toby or Damien asked about test investigations and the surgical opinion and I hope that I've answered that. And Jason, I think similarly. Dan asked about treatment. As I say, Rob talks about the Newcastle regime, which is essentially an upper fibres of trapezius regime which you'd imagine is going to give you posterior tilt and open up that supraclavicular region. Certainly, anything that improves neck and shoulder strength in terms of having an unloading effect.
I think Dan had an interesting question about protraction, but I think we don't want to do anything that encroaches on that space. We actually want to open it out. So, it's not that we're depressing or pulling down, we're actually opening out by actually getting the rotator cuff and scapular muscles to do their job insuring our cervical spine. But in terms of the evidence, those, the upper fibres of trapezius perhaps seems to have some evidence to support it. The other thing that's interesting is sometimes the use of Botox in the scalenii, particularly if they're thought to be a problem if we have hypertrophy for whatever reason. But again, I think it's taking an encompassing approach to these things and again, there is some suggestions in those reporting guidelines. The purpose of running these videos really is to highlight awareness in terms of diagnosis, to try and make sure patients get to the right place in the right time.
I've really talked about the key criteria in terms of diagnosis, in terms of pain distribution and in terms of clear, clinical tests that you can use in your practice. I've also talked about the limitations of things like nerve conduction studies.
So, I think what's really crucial if we have a patient that fits those criteria for thoracic outlet, that we realise that we can't rely on nerve conduction studies and they're often normal and they're often confusing, but don't forget the relevance of that small fibre degeneration that Anna Schmid's research has shown us. And they're actually doing some very nice, simple clinical cost-effective tests using the coin, using a Neurotip seems to give us good value in terms of identified in that small fibre degeneration. We need to be honest, we still need more evidence and Rob Patterson in conjunction with Anna Schmid's trying to do a good job of actually populating some of that research for us. But I think that awareness and not ruling things out based on our imaging, because once again, we see the imaging is not without its flaws.
Now let me just have a look. We've got a few comments here. The Ridehalgh paper used participants diagnosed with Radiculopathy, if someone already has large fibre changes how accurate would their analysis of the small fibre sensory testing be?
Ooh, that's a great question. I think we can look at both those things. The point of telling you about the small fibres when I don't have that large fibre involvement because in the large fibre involvement my nerve conduction studies are likely to be more sensitive but equally when I do some of my other gross neurological testing I'm likely to pick things up. That work has also been done in patients with carpal tunnel syndrome.
I think you've all been very kind to me tonight because there don't seem to be any more questions so thank you. I know Rob's listening in this evening and I would definitely recommend that you go and have a look at his website.
I'm going to post some really useful references that I found extremely helpful. Now when I look at my practice, I probably see about three of these patients a year and that's within a specialist's upper limb unit. I think what the increasing evidence and understanding why my nerve conduction studies weren't infallible was just one of the most useful things in terms of understanding this complex condition. And remember, I've only talked about the neurogenic thoracic outlet tonight, but I hope it's given you some really lovely tips and tricks.
It's going to increase your awareness for this patient population. And as I say, what I generally see is these patients haven't been believed to have often had unnecessary surgery and have just had a very frustrating journey. So, don't forget to look into those reporting standards that we'll post on the Facebook page. I'll also post some other useful references just to really back up what I've talked to you about tonight but as ever thanks for joining.
Next Monday I won't be here because I'm actually lecturing a rugby club about rugby. But I will be here on Sunday instead at seven o'clock. Those of you who have joined us before, will know that if you can't join us at that time, don't worry, it'll be re-posted on the Facebook page. You can access all the information there and there'll be a summary as I say, of those key papers.
Once again, guys, thanks so much for giving up 25 minutes of your very precious time and coming to listen to me. We've continued our foray into shoulder diagnosis and just increasing our awareness of conditions that actually really, we perhaps need to signpost to other people and have a low threshold to refer on, but also knowing the ones that we can justify actually trying our physiotherapy interventions first.
So, thanks for joining us. I hope to have some Christmas decorations up behind me by next week and not doing very well on that front at the moment. Have a lovely run up to Christmas and I look forward to seeing you all again soon. Thanks again for joining.