Research Review By Dr. Michael Haneline©


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Date Posted:

April 2021

Study Title:

An Update of Systematic Reviews Examining the Effectiveness of Conservative Physical Therapy Interventions for Subacromial Shoulder Pain


Pieters L, Lewis J, Kuppens K, et al.

Author's Affiliations:

Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.

Publication Information:

Journal of Orthopaedic & Sports Physical Therapy 2020; 50(3): 131-41. doi: 10.2519/jospt.2020.8498.

Background Information:

The clinical presentation of subacromial shoulder pain (SSP) involves pain and impairment of shoulder movement and function that typically occurs during shoulder elevation and external rotation (as in throwing or other overhead sporting activities). Structures implicated in the pathogenesis of SSP include the subacromial bursa, the rotator cuff muscles and tendons, the acromion, the coracoacromial ligament and capsular and intra-articular tissues (1).

Mechanical factors that have been hypothesized as contributing to the pathogenesis of SSP include altered shoulder kinematics associated with capsular tightness, rotator cuff and scapular muscle dysfunction, overuse due to sustained intensive work, and poor posture. Nonetheless, the pathogenesis may be multifactorial which has led to a variety of possible treatment recommendations (2, 3).

Littlewood et al. (4) conducted a systematic review on the management of rotator cuff tendinopathy in 2013, reporting that exercise and multimodal physical therapy might be effective, although the magnitude of improvement was uncertain. The aim of this current review was to update these findings to determine whether more recently published literature provided further understanding of the best approach for the clinical management of SSP.

Pertinent Results:

Literature Search Results & Research Quality:

After screening articles found in the literature search and removing duplicates and articles that were not relevant, 16 studies were selected for inclusion in this review.

The AMSTAR quality appraisal process determined that 9 out of 16 studies were of high quality, while the remaining 7 studies were of moderate quality. The reason some studies were downgraded was because the review authors did not consider the possibility of publication bias.

Evidence and recommendations regarding the various modalities for SSP are as follows:
  • Exercise: Based on 7 systematic reviews, moderate- to high-level evidence supported the use of supervised shoulder exercises, home-based shoulder exercises, as well as strengthening and stretching exercises. The authors, therefore, made a strong recommendation in favor of exercise therapy for patients with SSP. However, they recommended that future reviews and research should focus on the types of exercise therapy that are utilized (ex. strength, repetitions).
  • Exercise combined with manual therapy: Six systematic reviews of variable quality covered the effect of manual therapy combined with exercise. There was moderate- and high-level evidence that manual therapy along with exercise reduced pain in the short term and low-level evidence that there was no significant improvement when exercise was combined with manual therapy. Therefore, a strong recommendation was made in favor of exercises combined with manual therapy.
  • Multimodal physical therapy: Three variable quality systematic reviews reported on the effect of multimodal physical therapy, defined as combined nonsurgical treatment, including passive physical modalities, exercise, manual therapy, taping, corticosteroids, or electrotherapy. There was low-level evidence supporting exercise combined with other therapies (Kinesio Taping, specific exercises, and acupunc¬ture) and the effectiveness of taping as adjunct therapy was weak for improvement of pain, disability, range of motion, and strength. The authors, therefore, only gave a weak recommendation for including multimodal therapy in the management of SSP.
  • Corticosteroid Injection: Four systematic reviews of variable quality covered the effectiveness of corticosteroid injection for SSP. One moderate-quality study reported improvements in pain and shoulder function immediately after corticosteroid injection that was superior to no therapy and physical therapy modalities. The authors gave a moderate recommendation for corticosteroid injection as a solitary treatment or in addition to exercise-based therapy.
  • Laser Therapy: Six systematic reviews of variable quality covered the effect of laser therapy on SSP showing mixed results, from no evidence of benefit in the treatment of SSP to moderate-level evidence, indicating that laser therapy could reduce pain and improve function when used as an adjunct therapy to exercise or in a physical therapy treatment program. Because there was no evidence supporting the effectiveness of laser therapy as a monotherapy compared to other interventions, a strong recommendation was given to not use laser therapy in the treatment of SSP.
  • Ultrasound: Based on 5 variable quality systematic reviews evaluating the effectiveness of ultrasound for SSP, which consistently concluded that there was no evidence of effectiveness, a weak recommendation was given to not use ultrasound.
  • Extracorporeal Shockwave Therapy: Three systematic reviews that were of variable quality consistently concluded that the evidence did not support the effectiveness of extracorporeal shockwave therapy.
  • Pulsed Electromagnetic Energy: Four variable quality systematic reviews all reported no significant effect of pulsed electromagnetic energy on pain reduction or improvement of shoulder function compared to placebo. A strong recommendation was given that pulsed electro-magnetic energy is not an effective for treatment for SSP.

Clinical Application & Conclusions:

This review gave strong recommendations for the treatment for subacromial shoulder pain (SSP) using exercise, performed at home and/or at a clinic, as well as manual therapy when combined with exercise. Moreover, the evidence supporting exercise as the most important management strategy for SSP is increasing and strengthening.

No clear conclusions were provided regarding the effectiveness of multimodal therapy, so only a weak recommendation for its use was provided.

A moderate recommendation was given regarding the effectiveness of corticosteroid injection as an isolated treatment or along with exercise-based therapy.

There was a lack evidence on the effectiveness of therapeutic ultrasound, low-level laser, extracorporeal shockwave therapy, and pulsed electromagnetic energy. Therefore, these modalities should not be used when managing patients with SSP.

Study Methods:

This was a systematic review in which the PubMed, Web of Science and CINAHL databases were searched independently by 3 researchers. Studies were selected for inclusion also by 3 reviewers working independently. Any differences between the reviewers’ selections were subsequently settled by consensus.

Inclusion criteria:
  • Systematic reviews that included randomized controlled trials (RCTs) involving people with signs and symptoms suggestive of SSP.
  • Systematic reviews had to evaluate the effectiveness of the following nonsurgical, nonpharmacological treatments: exercise, exercise combined with manual therapy, multimodal physical therapy, corticosteroid injection, laser, ultrasound, extracorporeal shockwave therapy, or pulsed electromagnetic energy.
Corticosteroid injection is not considered a nonpharmacological treatment but was included because it was covered in the Littlewood et al. systematic review and is strongly related to physical therapy rehabilitation of this condition.

The following diagnostic categories were considered equivalent to SSP: rotator cuff tendinopathy, painful arc syndrome, subacromial bursitis, rotator cuff tendinosis, supraspinatus tendinitis, and contractile dysfunction.

A data-extraction tool that was developed for this review was used independently by 3 reviewers to extract data from the included reviews.

The AMSTAR (A MeaSurement Tool to Assess systematic Reviews) checklist was used independently by 3 reviewers to appraise the included studies’ methodological quality. The AMSTAR checklist categorizes a systematic review’s quality as being of high quality, moderate quality or low quality.

The strength of individual recommendations was established as follows:
  • Strong recommendation: at least 50% of the reviews considering a specific topic had at least moderate-level evidence, with at least 1 review having high-level evidence.
  • Moderate recommendation: at least 50% of the reviews had moderate-level evidence.
  • Weak recommendation: fewer than 50% of the reviews had moderate-level evidence.

Study Strengths / Weaknesses

This update of a previous systematic review was well-done and provides a clearer understanding of the strengths and weaknesses of the various treatment modalities for SSP.

The authors listed several study limitations, as follows:
  • The methodological quality of the systematic reviews included in this review was moderate (mean AMSTAR score 7/11), as were those included in the Littlewood et al review (mean AMSTAR score 6/11).
  • The different comparison groups that were present in the included reviews were too diverse to present a clear overview.
  • It is possible that multiple primary studies were included in various systematic reviews which may have resulted in the interventions that were studied the most being overrepresented. On the other hand, some pertinent nonsurgical interventions may have been missed in the literature search.
  • Different terms are used to describe SSP, which could have resulted in the included reviews missing relevant RCTs that used other terms to describe this shoulder problem.

Additional References:

  1. Holmgren T, Hallgren HB, Öberg B, Adolfsson L, Johansson K. Effect of specific exercise strategy on need for surgery in patients with subacromial impingement syndrome: randomised controlled study. Br J Sports Med 2014; 48: 1456-7.
  2. McCreesh K, Lewis J. Continuum model of tendon pathology – where are we now? Int J Exp Pathol 2013; 94: 242-247. iep.12029.
  3. Wilk KE, Obma P, Simpson CD, 2nd, Cain EL, Dugas JR, Andrews JR. Shoulder injuries in the overhead athlete. J Orthop Sports Phys Ther 2009; 39: 38-54. jospt.2009.2929
  4. Littlewood C, May S, Walters S. A review of systematic reviews of the effectiveness of conservative interventions for rotator cuff tendinopathy. Shoulder Elbow 2013; 5: 151-167.