Subacromial pain syndrome : an experimental clinical investigation in primary care

This thesis presents the desired management for patients with Subacromial Pain Syndrome (SAPS) in primary care and consists of four papers based on data from two randomized controlled trials.

Background: SAPS is a multifactorial diagnosis and one of the most common shoulder problems in patients seeking physical therapy in primary care. The diagnosis is set clinically, and therefore it is important that physiotherapists know how to examine the patients to set the diagnosis at an early stage, to further motivate and guide the patients to best treatment. Today, graded exercise therapy is consensus on the treatment for these patients. Non- steroidal anti-inflammatory drugs, corticosteroids and operative treatment have been debated for treating this group of patients. Arthroscopic subacromial decompression together with post-operative rehabilitation is in most cases only recommended if non- operative treatment has been unsuccessful. Despite agreement on graded exercise therapy, there is still unknown how to carry out exercise programs to optimize the treatment for SAPS patients in clinical practice.

Aim: The overall aim was to evaluate the efficacy of a standardized progressive exercise program for the rotator cuff and scapular stabilizers supervised by a physiotherapy in a clinic or performed as a home training program, and to investigate whether an addition of joint mobilization could further improve clinical outcome. A second aim was to compare the imaging findings of both shoulders in patients with unilateral SAPS. A third aim was to study if a one- question score correlated with more extensive outcome scores.

Methods: A total of 170 patients, mean age 45 years, diagnosed with SAPS were randomized to different treatment groups such as physiotherapy guided exercises (Study 1) or home-based training (Study II), with or without joint mobilization or, to a control group that did not receive any treatment. The diagnosis was set based on clinical examination by a physiotherapist according to different recommended clinical tests. Furthermore, the patients were examined with diagnostic musculoskeletal ultrasound (Study III). A description of the ultrasound findings of both the symptomatic and non-symptomatic shoulder were performed (Study III). The patients were also evaluated with the Constant-Murley score (C- M score), Western Ontario Rotator Cuff Index (WORC) and the Single Assessment Numeric Evaluation (SANE) score at baseline and at three- and six-months follow-up (Study IV). The SANE score consists of only one question whereas the other scores are more detailed and therefore more time consuming to complete. A test for a possible correlation between these scores was performed (Study IV).

Results: Shoulder function improved in all groups over time. Based on the C-M score all patients with SAPS significantly improved their shoulder function with guided exercise when compared to no treatment (Study I), but not when comparing home training to no treatment (Study II). In the subscale pain both intervention groups reported less pain than the control group at six weeks, three and six months (Study I) and at three months with home training (Study II). Add-on joint mobilization resulted in decreased pain in active range of motion at six weeks and at three months in comparison with guided exercise and no treatment in Study I (p<0.05) and at three and six months compared to home training or no treatment in Study II (p<0.05). Ultrasound anomalies were seen in both shoulders and increased with age (p<0.05), however more frequently on the affected side (p<0.05), where bursal thickening was the most common finding and Supraspinatus the most affected muscle (Study III). The one question SANE score correlated well with more extensive scores at the three- (r= 0.609- 0.692) and six-month (r= 0.787- 0.793) follow-up (Study IV).

Conclusions: Guided exercise was the best choice in patients with SAPS evaluated with the C-M Score. Add-on joint mobilization in the beginning of a treatment period, led to decreased pain. Ultrasound findings were seen in both shoulders in patients with unilateral SAPS and must be taken into consideration when diagnosing SAPS. The SANE score, a one question score may replace more extensive scores when evaluating the progress of the treatment in non-operatively treated patients with SAPS.

List of scientific papers

I. Guided exercises with or without joint mobilization or no treatment in patients with subacromial pain syndrome: a clinical trial. Anna Eliason, Marita L Harringe, Björn Engström, Suzanne Werner. J Rehabil Med. 2021 May 11;53(5):jrm00190.
https://doi.org/10.2340/16501977-2806

II. Home training with or without joint mobilization compared to no treatment: a randomized controlled trial. Anna Eliason, Suzanne Werner, Björn Engström, Marita L Harringe. Phys Ther Sci. 2022 Feb;34(2):153-160.
https://doi.org/10.1589/jpts.34.153

III. Bilateral ultrasound findings in patients with unilateral subacromial pain syndrome. Anna Eliason, Marita L Harringe, Björn Engström, Kerstin Sunding, Suzanne Werner. Physiother Theory Pract. 2021 Aug 17;1-12.
https://doi.org/10.1080/09593985.2021.1962462

IV. A single assessment numeric evaluation score may be a time efficient rating scale in patients with unilateral subacromial pain syndrome. Anna Eliason, Suzanne Werner, Björn Engström, Marita L Harringe. [Submitted]