Rotator cuff-related shoulder pain: Is it time to reframe the advice, "You need to strengthen your shoulder”?

Key Points

1. Individuals with rotator cuff-related shoulder pain typically present with deficits in strength, muscle activation, and kinematics compared to pain-free individuals. However, improving these factors may not be necessary to achieve positive clinical outcomes.
2. Although strength training has been shown to improve clinical markers of pain and function, the mechanism of action is multi-faceted.
3. The rationale for prescribing strength training exercises for shoulder pain should be framed within a context of helping individuals improve their quality of life, rather than just simply getting stronger.

BACKGROUND & OBJECTIVE

The diagnosis of rotator cuff-related shoulder pain (RCRSP) has evolved into a clinical conundrum. Attempting to identify the pathoanatomical pain-generating source and distinguishing between bursitis, tendinitis, impingement, or a cuff tear can be futile.

Many practitioners have abandoned methods they once relied on, as both advanced imaging and special tests are consistently shown to be hypersensitive and insufficiently specific (1,2). The ambiguity of diagnosis, variability in symptoms, and relative success of non-surgical intervention has led to a deeper investigation and a growing body of evidence supporting conservative treatment (3).

Although there is robust research supporting a wide variety of conservative interventions, including at-home therapy, education, gentle exercise, and manual therapy for shoulder pain, many clinicians are now favoring a “just strengthen it” resistance training approach to treating RCRSP (4).

While exercise therapy is undoubtedly important in the management of RCRSP, there is uncertainty regarding which approach is best and the absolute benefit of exercise compared to non-exercise interventions. It would be wise for clinicians to take a step back in order to better understand the overall mechanism of action and how to best structure their interventions.

Special tests of the shoulder are consistently shown to be insufficiently specific.

Exercises should be chosen in a manner that helps patients reduce the burden of their decreased shoulder function and resume meaningful activities.

METHODS

The authors of this viewpoint paper utilized 15 papers to inform their writing, while providing 23 additional resources in an appendix containing recommendations for further reading. No data was used in this paper.

RESULTS

It is thought that clinicians have gravitated towards a strengthening and structural-based approach to treating shoulder pain due to the success of conservative treatment and the typical presentation of decreased strength and range of motion in RCRSP patients. While this approach appears to be sensible at face value, it has been called into question due to the incongruency between clinical outcomes and mechanical improvements in shoulder function.

Many patients with RCRSP who undergo strength training interventions experience decreased pain and increased function despite showing only minor to moderate improvements in their strength, and negligible changes in their mechanics and activation patterns. The authors suggest these clinical phenomena should challenge our understanding of the relationship between shoulder strength, shoulder function, and pain.

The ideas put forth in this viewpoint are consistent with research on scapular mechanics, as altering the scapulohumeral rhythm or seeking visual scapulothoracic symmetry has not been shown to be necessary for improving pain and function (5). Clinicians should adopt a more modernized approach to understanding how interventions affect patients, including the consideration of biopsychosocial factors, pain-related self-efficacy, and a potential re-evaluation by the patient of the severity of their pain and its impact on their quality of life.

Exercise should be used as a conduit to assist patients in resuming meaningful activity and reach their goals, however the method by which we measure its effectiveness might need to be reconsidered.

LIMITATIONS

All viewpoint and opinion papers have an inherent limitation in that they are not data-driven research. Viewpoints nonetheless are a valuable contribution to the body of research, and reputable journals such as the Journal of Orthopedic & Sports Physical Therapy and British Journal of Sports Medicine routinely champion them.

Regardless, viewpoints fall in the lowest tier of the evidence hierarchy. Viewpoints that are published in reputable journals and have undergone a peer review process should be used as an adjunct to an evidence-informed working knowledge. They offer a means to reach beyond the current base of evidence to direct future research, question commonly held beliefs, and spark productive dialogue.

CLINICAL IMPLICATIONS

The primary clinical takeaway from this viewpoint is to not over-simplify the mechanism of action of improvement for RCRSP patients. Clinicians should continue to use therapeutic exercise, and more specifically resistance training for the treatment RCRSP, however they would be remiss to believe that ‘strengthening’ was the only mechanism of improvement for their patients.

Exercises should be chosen in a manner that helps patients reduce the burden of their decreased shoulder function and resume meaningful activities. The ideas in this viewpoint run parallel to emergent research on low back pain, as core stabilization and strengthening has come into question as a primary means of improving markers of pain and disability (6).

Clinicians should be motivated to look beyond a structural view of their patients and adopt a biopsychosocial method of reasoning. This viewpoint, along with a large body of research over the past two decades, serves an important role in creating dialogue regarding how patients achieve positive clinical outcomes. Despite the biological plausibility behind taking a classical recipe-based approach to prescribing therapeutic exercise, there are many factors that influence patient outcomes.

In addition to therapeutic exercise, physical therapists should be considering how debilitating and impactful upper extremity pain can be to their patients’ quality of life, and how they can structure therapeutic interventions to help them improve their confidence, self-efficacy, independence, and function.

+STUDY REFERENCE

Powell J & Lewis J (2021) Rotator Cuff-Related Shoulder Pain: Is It Time to Reframe the Advice, "You Need to Strengthen Your Shoulder"?. JOSPT, 51(4), 156-158.

SUPPORTING REFERENCE

1. Paul Salamh, Jeremy Lewis. (2020). Is It Time To Put Special Tests for Rotator Cuff Related Shoulder Pain Out to Pasture? JOSPT
2. Barreto RPG, Braman JP, Ludewig PM, Ribeiro LP, Camargo PR. (2019). Bilateral Magnetic Resonance Imaging Findings In Individuals With Unilateral Shoulder Pain. J Shoulder Elbow Surg.
3. Boorman Richard S, et al. (2017). What happens to patients when we do not repair their cuff tears? Five-year rotator cuff quality-of-life index outcomes following non-operative treatment of patients with full-thickness rotator cuff tears. Journal of Shoulder and Elbow Surgery.
4. Ariel Desjardins-Charbonneau, Jean-Sébastien Roy, Clermont E. Dionne, Pierre Frémont, Joy C. Macdermid, François Desmeules. (2015). The Efficacy of Manual Therapy for Rotator Cuff Tendinopathy: A Systematic Review and Meta­analysis. JOSPT
5. Camargo, P. R., Alburquerque-Sendín, F., Avila, M. A., Haik, M. N., Vieira, A., & Salvini, T. F. (2015). Effects of Stretching and Strengthening Exercises, With and Without Manual Therapy, on Scapular Kinematics, Function, and Pain in Individuals With Shoulder Impingement: A Randomized Controlled Trial.  JOSPT.
6. Coulombe, B. J., Games, K. E., Neil, E. R., & Eberman, L. E. (2017). Core Stability Exercise Versus General Exercise for Chronic Low Back Pain. Journal of athletic training, 52(1), 71–72. https://doi.org/10.4085/1062-6050-51.11.16