Critical Thinking

Posture And The Shoulder

A few years ago I got into an interesting conversation with a colleague about the importance of static posture in patients with impingement syndrome (SIS). She was convinced that the literature showed that posture was an important factorposture in subjects with SIS and I had a different perspective. After this conversation I started doing some poking around in the literature. As I put more and more time into this endeavor, and was unable to find a literature review on the topic, I decided to write one. This review was recently published in Physical Therapy Reviews and I encourage you to take a look.

After lots of searching and reading I found 9 articles which looked at posture in subjects with SIS. All 9 of these studies found no connection between SIS and posture. To make sure I was thorough I included 15 other studies which provided information on the subject but did not specifically look at self- selected resting posture in subjects with SIS. For example, they may have looked at asymptomatic subjects, subjects with neck/shoulder pain or non self-selected postures. These 15 studies had mixed results with 9 of them providing some support for the plausibility of a connection between SIS and posture. For example, Borstad et al found a relationship (in asymptomatic subjects) between pectoralis length and scapular mechanics similar to those seen in subjects with SIS. In a subsequent article they connected pectoralis length with postural findings such as kyphosis and scapular internal rotation. These two studies suggest a mechanism by which posture and SIS could be connected, however this connection has never been demonstrated in a symptomatic population.

To continue in my attempt to be thorough, I also included 7 studies which looked at treatments aimed at postural correction. Of those seven, only one looked specifically at postural correction in subjects with SIS. This study found that postural correction increased pain free ROM but did not change overall pain levels. The problem with this study is that they did not differentiate between shoulder complex motion and simply increased elevation due to contributions of thoracic extension. So it is possible that the subjects’ shoulders did not move more, rather they simply got more apparent elevation due to thoracic motion. There were 3 studies which indicated that exercise can have an effect on posture, however it is unclear if the changes were meaningful or long lasting.

Since finishing the search for my article, two additional noteworthy articles have been published on the topic. Both of these studies have the same lead author, Filip Struyf from Belgium. This study published in Int J Sports Med is the first prospective study I have found on the topic. This study followed 113 overhead athletes for 2 years and 25 (22%) of them developed shoulder pain. Baseline measurements of scapular dyskinesis, protraction, upward rotation, dynamic scapular control and acromial distance were not predictive of future shoulder pain. The second study published in Clin Rheumatol looked at stretching and motor control exercises versus stretching, muscle friction and eccentric cuff exercises for treatment of SIS. The group that performed the motor control exercises had the most improvement, however these improvements were not associated with changes in scapular measurements (upward rotation, forward shoulder posture, strength, motor control or pec minor length). This suggests that although the motor control exercises may have been helpful, their effect was not due to changes in posture or motor control.

Despite this lack of evidence for a connection between posture and SIS, there still seems to be strong beliefs in and out of our profession about the importance of posture. If we look at SIS as a disorder caused by abnormal mechanical pinching it does make a lot of sense that certain postures could increase this pinching. However, if we look at SIS as a more complex disorder that may not be strongly associated with pinching, it becomes easier to understand why posture may not play a large role in this disorder.

 

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Categories: Critical Thinking, research, Shoulder

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6 replies »

  1. Hi Adam,
    Once again a very thought provoking, well written article from the team at Forward Thinking. As always with these blogs there are the citations that shows that the ‘current, accepted’ model may not be valid but I’d also be interested to know what citations you have that show that an alternative approach (whatever that might be) is more valid. I think there’s a saying about ‘throwing stones at a glass-house’ which comes to mind, it’s all good & well for you to propose that current methods are misplaced but I feel you undermine yourself by not presenting alternative evidence.

    I appreciate that the blog atmosphere is not the most appropriate environment and I’m sure you may also be protecting some Intellectual Property but the IP issue aside just citing your evidence from what I assume was a thorough review doesn’t really help me as a clinician. As manual therapists I think it’s healthy to have a fair degree of scepticism about some of the things we do with respect to assessment and treatment and keep an open mind and to have individuals that challenge long-held beliefs but your argument would have more strength if you provided concrete alternatives.

    My experience tells me that patients come to us for several reasons, pain is usually primary, but amongst others they need/want answers and an explanation. If I can provide them with what appears to a likely scenario & we systematically target those prevailing features (such as posture for shoulder problems) then we get a positive outcome. If I am not believable in my explanation we get less satisfactory outcomes, here I think we are dealing with the placebo effect. I personally have no issue with the placebo, in fact I know much of what I do is placebo driven but in order to have an effect you still need to do something that in the patients mind appears believable. You can’t just sit back & say to them oh don’t worry about your posture it has nothing to do with your shoulder problem.

    I hope I’ve made some sense. Thanks again for your thought provoking ideas.
    Cheers
    Taso

  2. ADAM, as Taso mentioned, the article is well written and thought provoking… how ever, I’m not quite sure that the evidence that you cite as being NOT CONVINCING, is really not convincing for many others…
    Janda used to say that posture assessment should only be the entry window for many more tests to come..
    Cyriax used to say that we should not rely on a single test or finding…
    Meaning, you could take standing posture info and continue to perform muscle length, movement pattern testing, provocation testing and so on…
    At the same time, I agree with Taso that the study you provide citing it as a “more complex” issue, does not provide any evidence that standing posture does not play a role, nor provides an alternative… (it just goes deeper on the site of the lesion)
    Again, I’m all in for Biopsychosocial approach and I’m all in about NEUROSCIENCES…NO issues with them.. but the mechanical component is IN the model… Regards, David

  3. David,

    Years ago the hypothesis that posture impacts the pinching that occurs in SIS was put forward. Since that time it has been considered by many to be an accurate hypothesis. The burden of proof is not to disprove the hypothesis it is to prove it is true. As you demonstrate above, we can always come up with new justifications (maybe this, maybe that) for why a given hypothesis might be true; which makes disproving a hypothesis nearly impossible. As a result, the scientific process has us accept the null hypothesis until sufficient evidence is produced which proves it true. I cannot say that there is no connection between SIS and posture, I can simply say that the current evidence does not support it. I looked at many articles and I even looked at articles which were a bit tangential to my question and I still could not support the SIS/posture hypothesis. There is also evidence which suggests SIS is not a primary mechanical problem which would provide an explanation for this lack of connection.

    Taso,

    Good point about my lack of comment on what I think we should do given this information. 1) I think we need to stop harping on posture. I am not saying that posture is never a factor, however I think it is not a major factor most of the time. 2) When speaking we should be accurate with our patients and not falsely convince them that to get better their posture needs to change. 3) This information does not negate the other data which shows exercise and (to a lesser extent) MT is helpful. It may change why we do exercise and who we do it for. It is possible that even in the absence of poor posture or scapular dyskinesis motor control exercises may be helpful.

  4. Dear colleagues.
    As a physiotherapist with 35 years of post grad training and experience only last year did I discover the work being done in France for the past 90 years on the neuroscience of posture and alignment …it makes so much sense ( also more evidence than I have seen for most of what we do as physios ) and the results I am getting vastly outweigh all the very narrow ” one joint ” “or upper quadrant ” thinking I have been taught,
    Turns out( contray to what was taught in med school ) we have a perfectly evoloved postural system whose sensors are the eyes,feet,skin and tmj who communicate with each other via extrapyramidal pathways to ensure we are intaking the most correct postural information to ensure symmetry in 3 planes with optimal spinal curves.

    Please I urge you to look at this work and be prepared to integrate the brain into the body and see issues like shoulder dysfunction as a symptom not a cause …and postural dysfunction as a symtpom of an overall underfunctioning neurological system which affects human learning as well as sports performance.
    http://www.posturepro.ca
    http://www.matboule.com ( chief instructor on the Posturology program )

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