A previous systematic review had concluded that, when compared to strengthening exercises, motor control exercises might lead to small short-term benefits of uncertain clinical significance for adults with rotator cuff-related shoulder pain, but that new trials of adequate quality were warranted.
This blog summarizes the results of a randomized controlled trial that was recently published in the British Journal of Sports Medicine. The authors are from Canada and the United Kingdom and have research and clinical expertise in the management of shoulder-related musculoskeletal disorders. If you have any questions or would like to discuss this study in more detail, please feel free to contact the author of this blog, who happens to be one of the authors of the study, at firstname.lastname@example.org or on Twitter @marco_dube.
Shoulder pain is a very prevalent musculoskeletal disorder as highlighted by the 70% of individuals who will experience an episode of shoulder pain throughout their lifetime. Unfortunately, 50% of those will still report recurring or persisting symptoms 12 months after initial onset. Among the diagnoses encountered in clinical practice, rotator cuff-related shoulder pain has been identified by experts in the field of shoulder pain as a broad term that encompasses many frequently encountered diagnostics labels such as rotator cuff tendinopathy, subacromial impingement syndrome, subacromial pain, and partial atraumatic rotator cuff tears. Even though many interventions, such as exercises, education, and injections have shown to be effective, close to 30% of patients do not experience a significant improvement in their symptoms, no matter the intervention(s) used. One possible explanation for this lack of effectiveness might be the selection of exercises prescribed by clinicians. A previous systematic review had concluded that, when compared to strengthening exercises, motor control exercises might lead to small short-term benefits of uncertain clinical significance for adults with rotator cuff-related shoulder pain, but that new trials of adequate quality were warranted.
Thus, the aim of this randomized controlled trial was to compare three different ways of managing rotator cuff-related shoulder pain: 1) Education only; 2) Education combined with motor control exercises; 3) Education combined with strengthening exercises. Our research team aimed to evaluate if one of these three frequently used interventions could lead to greater pain and/or symptom reduction. We also aimed to evaluate if the interventions led to different results regarding acromiohumeral distance, shoulder muscle strength, and psychological characteristics associated with persistent pain.
To answer this question, we conducted a three-arm parallel group randomized controlled trial. We recruited 123 adults with persistent rotator cuff-related shoulder pain and randomly allocated them to one of three 12-week interventions.
Education and advice: Participants in this group took part in an initial 30-minute session with a physiotherapist where they received information on their shoulder and their pain and advice on activity modification and the importance of healthy lifestyle choices (hydration, nutrition, sleep, physical activity, stress management). They also had to watch six short videos at home on those topics before discussing them with the physiotherapist during a second 30-minute session where any of their remaining questions were answered.
Education combined with motor control exercises: In addition to the same education intervention given to the first group, participants in this group underwent an exercise program aiming to facilitate arm movement to allow for a less painful movement and to reduce potential compensations. Once participants had achieved pain-free simple elevation movements of the shoulder, exercises progressed to more functional movements mirroring activities of daily living such as lifting, throwing, precise movements, pushing, pulling, catching, and carrying. Participants had to perform their program of five to six exercises every day.
Education combined with strengthening exercises: In addition to the same education intervention given to the first two groups, participants in this group received an exercise program aiming to potentially increase strength through higher loads. The strategy used to prescribe exercises in this group could be defined as a high load/low repetitions regiment. The load prescribed was matched to 80 to 90% of 1 repetition maximum which equates to a load that allows four to eight repetitions until muscular fatigue prevented them from doing more. Selected exercises targeted humeral internal/external rotators, abductors, and the scapular muscles. Participants had to perform their program of seven exercises every day.
Symptoms, function, pain, kinesiophobia, pain catastrophizing, and pain self-efficacy were assessed at baseline, 3, 6, 12, and 24 weeks using validated patient-reported outcome measures such as the QuickDASH, the Western Ontario Rotator Cuff Index (WORC), the Brief Pain Inventory Short-Form (BPI-SF), the Tampa Scale of Kinesiophobia (TSK), the Pain Catastrophizing Scale (PCS) and the Pain Self-Efficacy Questionnaire (PSEQ). Peak isometric shoulder strength in abduction and external rotation was assessed at baseline and 12 weeks using a hand-held dynamometer and ultrasound measurements of the acromiohumeral distance at 0° and 60° of arm abduction were measured at baseline and 12 weeks using valid and reliable methods.
Although all three interventions were effective in improving symptoms, the addition of strengthening or motor control exercises did not lead to additional benefits compared with education alone. The same was true for psychological characteristics as individuals from all three groups experienced a statistically significant reduction in pain catastrophizing and kinesiophobia and a statistically significant improvement in pain self-efficacy without any group showing superior outcomes. Finally, at the 12-week follow-up, there were no significant between-group differences for peak isometric shoulder strength in abduction or external rotation and no significant between-group differences for ultrasound measurements of acromiohumeral distance at 0° and 60° of arm abduction.
Those results may be surprising to some but other recently published high-quality studies looking at interventions for rotator cuff-related shoulder pain, such as the SExSI and the GRASP trials, have also shown that more extensive exercise interventions don’t seem to lead to additional benefits compared to best practice advice or usual physiotherapy care.[8,9]
Clinicians can consider education and advice as an effective first-line intervention for persistent rotator cuff-related shoulder pain. They should remember that education and advice must be one of the key components of the management and be individualized based on the patient’s characteristics. Education delivered to patients can touch on topics such as load management and activity modification, pain self-management, and the importance of being physically active and prioritizing healthy lifestyle choices.
Even though the addition of exercises did not lead to additional benefits in our study, clinicians can still consider including them as part of patients’ management as they represent a low-cost intervention with very few adverse events. Exercises are also an important component of a healthy lifestyle and they are a key intervention in promoting sustainable health and the maintenance of functional autonomy over time.