In this episode of the Shoulder Physio Podcast, I'm giving a monologue my second ever monologue. I'm going to be discussing an editorial of mine published in the Journal of Orthopedic and Sports Physical Therapy. Otherwise known J O S P T in the year 2020. The paper is titled "Rotator Cuff Related Shoulder Pain. Is it time to reframe the advice you need to strengthen your shoulder?" The form and structure of this podcast will be slightly different than usual. I will read the paper verbatim, but will sporadically pause for reflection along the way, providing more detail in nuance when needed. Because the paper isn't editorial, it is pretty short. It's only 1500 words or so, and thus I may have glossed over the main points of the paper too briefly. This is the nature of word count limitations. Therefore, the addition of more detail and nuance may be helpful for you.
I hope that by doing this podcast I can clarify some confusion about the main thesis of the paper. I've actually been quite surprised at the consistent misinterpretation and straw manning of the paper, mostly coming from people who have been shouting loudly on the internet about the all curing nature of strengthening exercise. Over the past two decades, evidence supporting non-surgical management of non-traumatic rotator cuff related shoulder pain has grown. The most recent clinical practice guideline recommends advice, education and non-surgical management as the primary approach to managing rotator cuff related shoulder pain. Non-Traumatic rotator cuff related shoulder pain is pain and dysfunction of the shoulder commonly observed during shoulder elevation and or external rotation for which other conditions have been excluded, such as a truly stiff shoulder or an unstable shoulder.
Terms such as cuff related shoulder pain and subacromial shoulder pain, for example, may be more appropriate than traditional patho anatomic diagnoses of the rotator cuff and related structures including subacromial bursitis, rotator cuff tendinopathy, and partial and full thickness rotator cuff tears As it is difficult to identify a specific structure or pathology as the primary contributor to an individual shoulder pain. The clinical presentation of rotator cuff related shoulder pain is always influenced by individual cognitions, emotions, behaviors, and sociocultural factors that further complicate the pursuit of a single structure that causes shoulder pain boing. Now for reflection, so the ongoing debate about the most appropriate diagnostic label for rotator cuff related shoulder pain continues and probably will never end. Jeremy Lewis and I published a paper on this in the New Zealand Journal of Physiotherapy in 2022, and I have listed this paper in the show notes if you are interested.
Some prominent physio personalities reckon impingement is the term of choice and should remain the chief diagnostic label for Rotator Cuff Related Shoulder Pain. I find this utterly befuddling. We have evidence from both quantitative and qualitative research that clearly shows that the term subacromial impingement syndrome can ignite thoughts from the patient that imaging and surgery are required to fix or effectively manage their shoulder pain. And we know this isn't true. Moreover, the veracity and validity of the impingement diagnosis is seriously questionable. Remember that this impingement diagnosis was proposed 50 odd years ago, bulge by Charles neer on the back of a bit of anecdotal observation in his surgical practice. It really wasn't ever a strong theory. We have since spent the past 20 years studying this diagnosis to see whether it is valid or not and basically the, the research has pretty effectively refuted this diagnostic label.
I also have serious reservations about non-descript terms such as non-specific shoulder pain and shoulder sprain basically because of patient skepticism. I like middle ground terms such ASIC ator shoulder pain because it doesn't describe a pathology, but it also is tethered to something real in the world that is also coherent and in intellig intelligible to patients. And that is the rotator cuff. So because it doesn't describe a pathology, it doesn't say anything's torn or anything's inflamed, but because it is also tethered to something that is real and int intelligible in the world such as the rotator cuff, which is often linked to shoulder pain, I believe that the term rotator cuff related shoulder pain is probably the best that we've got at the moment. And this is also reflected in the evidence in terms of shoulder experts where there's a consensus study by Chris Littlewood in 2019, which suggests this, and also a survey which I've done published last year, which shows that most clinicians prefer the term rotator cuff related shoulder pain.
Okay, back to the paper. Now, quality nonsurgical management of rotator cuff related shoulder pain comprises a graduated or progressive program of resistance exercise against GRA gravity and with external load and occasionally in conjunction with stretching and mobility exercises of the shoulder structures and thoracic spine. If you are so inclined, the pendulum swinging towards nonsurgical management is underscored by research demonstrating that subacromial decompression surgery once the gold standard intervention for rotated cuff related shoulder pain does not confer superior outcomes to non-surgical approaches or placebo resistance. Exercise and strength training more broadly is riding a wave of popularity for various non-traumatic musculoskeletal pain presentations and should be considered a veritable poly pill with multi-system benefits. While exercise therapy has emerg as the primary intervention for managing rotator cuff float shoulder pain, there is uncertainty regarding which exercise approach is best and the absolute benefit of exercise compared to non-exercise interventions.
Pausing for reflection now. So if you were to go to PubMed and type in strengthening for shoulder pain or strengthening for musculoskeletal pain, you will observe an exponential increase in the number of studies exploring this topic topic in the last 10 to 15 years. Why? I reckon it's got something to do with the tendon research that became popular in the mid to late two thousands. Alfredson published his landmark eccentric loading for Achilles Tendonopathy paper in 1998. SEL published hers in 2001 and the cook and put continuum model of tendonopathy came out in 2009 and Jeremy Lewis applied this continual model to the rotator cuff in 2010. These papers all suggest that loading of which strengthening was crucial was a key part of managing tendon related pain. This research was trail, but trailblazing and I, I think quite decis decisive in going from a a physiotherapy model that was dominated by motor control type of exercises and stretching exercises and mobility exercises.
And it really privileged and championed the role of strengthening. And I think this has been absolutely terrific for the evolution of physiotherapy for tendon related pain, but have we become too obsessed with strengthening exercise. Now I will alert you to a disclaimer. My bias in my clinical practice and in managing my own injuries is strengthening exercise. And this will probably continue to be the case until I am confront confronted with level one evidence from a well conducted randomized control trial and perhaps a systematic review or meta-analysis of several randomized control trials that that shows me clearly that resistance or strengthening exercise is inferior to another type of approach. So my bias is strengthening, so please do not misinterpret that. Okay, returning to the paper now. So why do clinicians use resistance exercise for rotator cuff related shoulder pain? So clinical reasoning in physiotherapy or physical therapy or osteopathy or chiropractic is traditionally embedded within a biomedical framework insofar as we are trained to pursue a measurable physical impairment and if one is identified, apply an appropriate intervention to correct the impairment.
This model of clinical reasoning works under the guise that pain and dysfunction arise due to observable deficits in physical properties of the body. For rotator cuff related shoulder pain resistance exercise is typi typically prescribed to strengthen a weak shoulder resistance exercise may also be prescribed with the intent of improving shoulder girdle kinematics or timing and activations of peri shoulder musculature. The implication is an assumed isomorphic relationship or a one-to-one relationship between should shoulder strength, shoulder function and shoulder pain, increased strength to decrease pain and increase function. While this is biologically plausible, the reality is less certain. So movement and strength deficits characterize rotator cuff related shoulder pain. Can resistance exercise help people with rotator cuff related shoulder pain have changes in movement and strength that can be measured? Some people with rotator cuff related shoulder pain have altered scapular thoracic kinematics. However, there is wide spreading consistency in the type of alterations observed glenohumeral and scapular thoracic muscle timing and activity often measured by electromyography or E M G for short varies in people with rotator cuff related shoulder pain compared to people without symptoms.
People with rotator cuff related shoulder pain have deficits in external rotation and abduction strength of up to 50% when compared to an asymptomatic population. Strength deficits have also been observed in the scapular thoracic joint muscles, although not as profound as the glenohumeral joint muscles does. Improving shoulder mechanics and strength always improve pain and function. We suggest not strength gains with a typical rehabilitation regimen. For rotator cuff related shoulder pain are moderate at best and often clinically unimportant. Scapular kinematics or scapular dyskinesis need not be normalized for pain and function to improve and it is unclear where the scapular focused exercise interventions are superior to general shoulder strengthening. It would be clinically impossible to prescribe an exercise that targeted the scapular muscles at the expense of the rotator cuff and vice versa. Restoring shoulder muscle timing and activity appears superfluous to overall improvement of pain and function in people with rotator cuff related shoulder pain.
Despite the limited improvements in mechanical measures of the shoulder, there are often substantial improvements in pain and function in trials that use resistance exercise for rehabilitation. We suggest these clinical phenomena challenge the relationship between shoulder strength function and pain. Okay, pausing now for reflection in shoulder exercise research, there are a dearth of mediation analyses, which is a particular type of quantitative methodology that is used to identify mediators of outcomes. So this is the type of research that we need to actually determine if getting stronger or increasing strength or improving scapular kinematics is actually what mediates. So what is causally responsible for? The effect of exercise on pain and functional outcomes. Since this paper, my paper, the viewpoint that I'm reading was published in 2021, mediation analysis has been published and this was by hotter ATTEL 2022, which I'll list in the show notes. The results of this study report that scapular position and motion, so static scapular position and scapular motion and peri scapular muscle strength do not, and I repeat, do not mediate improvements in shoulder pain and function in people with rotator cuff related shoulder pain.
So scapular positions, scapular motion and periscapular muscle strength are not causally responsible for the improvements that we see in people with shoulder pain in response to an exercise program. So I'm gonna clarify again, what do I mean by media? A mediator is an intermediary variable. For example, strength that is causally influenced by an intervention. For example, resistance exercise and then causally influences an outcome. For example, pain. So a mediator is an intermediate variable, which is strength or scap kinematics that is causally influenced by an intervention, for example, resistance exercise, and then this intermediary variable then causally influences the outcome. This is a mediator returning to the paper Now. So why the limited increases in strength? Is it because of under loaded exercise and excessively cautious therapists? A frequent CRI critique of clinical trials using resistance exercise is they are under loaded and overly cautious. It is possible that a more stringent application of strength and conditioning principles such as intensity, volume, and duration of training could elicit a more dramatic increase in shoulder strength.
However, it is unclear if this would translate into similar improvements in shoulder pain and function. Trials that purport to employ high load resistance exercise often report underwhelming improvements in strength and it is unclear whether high dose, high load or high volume resistance exercise is clinically superior to low dose, which is low load or low volume resistance exercise for rotated cuff related shoulder pain. Okay, pausing for reflection. The dogmatic belief that high load or high dose exercise is better than low load or low dose exercise is unfounded, not just for shoulder pain either. Several papers exploring exercise for knee osteoarthritis over the last three years have shown this check the messier ETL 2021 paper in the show notes for an example, there was a section of the social media physio when strength and conditioning coach provocateur community that constantly said, the reason we get such bad results with resistance exercise in research is because it is under loaded.
This might still be true, however, the research as it currently stands, suggests otherwise we can't say that simply performing a high load exercise is sufficient to have a tangible and dramatic increasing strength that will then have a tangible and dramatic reduction in pain of the knee or of the shoulder or any other JO joint we want to talk about. Okay, so back to the paper. Now, have clinicians been seduced by the hype of strengthening manual therapy? Once a mainstay of nonsurgical management for rotator cuff later shoulder pain has not stood the test of rigorous trials. Many proponents of you only need to get strong may suffer a similar demise as the next generation treatment approach. Strength training has not yet passed muster through rigorous clinical trials, perhaps informing a person with rotate cuff related shoulder pain. You are weak. You simply need to get stronger, maybe as counterproductive as telling the person you have poor posture and it needs to be improved.
It is essential that clinical trials test modern strength and conditioning principles to establish a relationship between strength function and shoulder pain. Is there more to resistance exercise that meets the eye for rotator cuff related shoulder pain? Emerging evidence suggests non-traumatic rotator cuff related shoulder pain is a multi-dimensional condition associated with several bio psychosocial subdomains. The severity of shoulder pain and level of shoulder function do not appear strongly associated with shoulder strength. There is more to rotate a cuff related shoulder pain than simple strength, and the same could be said for resistance. Exercise. Exercise including resistance exercise may have a hyperalgesic effect, it may improve health related quality of life, improved pain related self-efficacy and confidence influence systemic inflammatory markers simply marked time while nature takes its course, provide a distraction and potentially lead to a reevaluation of pain. Clinicians might consider these factors when prescribing resistance exercise as part of a rehabilitation regimen for a person with non-traumatic rotator cuff related shoulder pain.
Okay, pausing for reflection. This is a crucial pause. I still propose that resistance exercise is the best bang for your buck exercise approach available for rotator cuff related shoulder pain. The compounding effect of regular resistance exercise for general and shoulder health is undeniable and I am a huge advocate. I recommend resistance exercise to over 80% of my shoulder patients, but I am simply asking you to consider that resistance exercise might be wor working via different causal mechanisms than simply increasing shoulder strength. So you need not adhere to strict strength and conditioning principles to help someone's pain. You can be flexible and versatile. However, if you are rehabilitating or seeing a high level athlete that needs to have a certain level of strength and power and endurance in their shoulder to perform at a higher level, then of course take this into account. But merely for pain, this probably goes beyond simply simple strength and conditioning principles.
Okay, back to the paper. Now. Integrating resistance exercise into a modern understanding of rotator cuff related shoulder pain. A modern interpretation of pain emphasizes a multi-dimensional experience far more than a simple linear readout of sensory input from the peripheral tissue. Perhaps clinicians could apply this logic to mechanical measures of the shoulder variables such as shoulder strength and scapular thoracic kinematics may be relevant to non-traumatic rotator cuff related shoulder pain. However, devoting an inequitable inequitable amount of time and detention to these factors may be a naive and inadequate approach. Summary, we are concerned that resistance exercise for managing rotated cuff related shoulder pain is at risk of becoming a blunt instrument used without critical thought in a classic recipe based approach awkwardly. This is an illustration of the type of biomedical clinical reasoning the profession of physical therapy has spent in the past due two decades or more, trying to avoid resistance.
Exercise has a place in a quality rehabilitation program for people with rotated cuff related shoulder pain to improve how the shoulder functions to increase shoulder confidence and help reduce pain. Resistance. Exercise is an important and cost-effective intervention, and physical therapists should not be afraid to use it. We argue there is nuanced to consider when using resistance exercise for rehabilitation. Okay, was this too long and you didn't read it? So T L D R here are five main points. People with rotator cuff related shoulder pain often have demonstrable variations in kinematics strength and muscle timing and activation profiles compared to people without rotator cuff related shoulder pain resistance exercise can improve shoulder pain and functional in function in people with rotated cuff related shoulder pain without normalizing shoulder mechanical factors of strength, scapular, thoracic kinematics, and muscle timing and activation. Non-Traumatic rotated cuff related shoulder pain is a multi-dimensional condition that requires a multidimensional approach. The rationale for prescribing resistance exercise for non-traumatic rotator cuff load to shoulder pain needs to be re reframed as a multi-dimensional intervention that can offer benefit by numerous interrelated bio psychosocial processes, not simply by increasing shoulder strength or improving shoulder mechanics. Future reser research should study the ideal dose of resistance exercise considering training variables such as intensity, volume, and duration for managing rotator cuff related shoulder pain.
Thank you for listening to this episode of The Shoulder Physio Podcast with yours. Truly, I hope I was able to clarify some possible misconceptions emanating from my paper. If you want more information about today's episode, check out our show [email protected]. If you liked what you heard today, don't forget to follow and subscribe on your podcast player of choice and leave a rating or review. It really helps the show reach more people. Thanks for listening. I'll chat to you soon. The Shoulder Physio Podcast would like to acknowledge that this episode was recorded from the lands of the terrible Lang people. I also acknowledge the traditional custodians of the lands on which each of you are living, learning, and working from every day. I pay my respects to elders past, present, and emerging, and celebrate the diversity of Aboriginal and Torres Strait Islander peoples and their ongoing cultures and connections to the lands and waters of Australia.
