Nov 15, 2021

Shoulder Impingement Syndrome

Shoulder impingement syndrome, also known as subacromial impingement or SIS, is a frequent source of shoulder pain [1]. It affects people of all activity and age levels [2]. SIS has two principal causes. It can occur due to an “intrinsic degeneration of the supraspinatus tendon,” which results in the “superior migration of the humerus” [3]. Alternatively, SIS can be caused by “extrinsic compression of the rotator cuff between the humeral head and coracoacromial structures” [3]. In either case, SIS can have a significant impact on patients’ daily lives, with the worst instances developing into long-term disability [2].

The clinical presentation of SIS can make diagnosis difficult. While the condition is often caused by trauma, pain is slow to develop [1]. A variety of other similar conditions, such as shoulder muscle imbalance, scapular disorders, and glenohumeral instability, also render diagnosis complicated [3]. As such, it is important for providers to keep in mind that shoulder impingement syndrome patients typically experience a decrease of strength, an impaired ability to engage in daily activities, and especially pronounced discomfort at night [1]. Generally, pain associated with SIS radiates from the anterolateral acromion to the lateral mid-humerus [1].

To diagnose SIS, doctors typically use arthroscopy or forms of radiographic evaluation, such as magnetic resonance imaging (MRI) [3]. Recently, researchers have contemplated alternative means of diagnosis. One such means is dynamic high-resolution ultrasonography. In a study consisting of 50 patients with reported painful shoulders, researchers tested how dynamic ultrasound exam compared to MRI as a diagnostic method for SIS [4]. They observed that dynamic ultrasound exam was more sensitive in assessing SIS and detecting abnormalities affecting patients’ shoulder joints than MRI, suggesting that it is a valuable diagnostic tool [4].

Treatments for SIS vary greatly. The first line of treatment consists of conservative modalities [2]. These options include physical therapy, steroid injections in the sub-acromial region, and rest [2]. Among the conservative options, exercise-based physical therapy has a high success rate [5]. Several studies have demonstrated how exercise treatments prevail over many other non-exercise treatments in improving patients’ function and decreasing their pain levels [5].

Many forms of physical therapy have been found effective in treating SIS. Past experiments have found that Codman exercises, Wand exercises, and resistive and isometric exercises of the shoulder girdle have all resulted in significant pain and functional improvements [6]. Physical therapy can also be effective when used in conjunction with other therapeutic modalities. For instance, Ucurum and colleagues found that exercise and hot packs, combined with interferential current, led to significant improvements in patients’ quality of life compared to other hybrid treatments [6]. Similarly, Kul and colleagues compared conventional physical therapy with kinesiotaping (KT) [2]. Although physical therapy was superior, their results suggested that KT may be beneficial as an additional source of care, alongside other treatments, for SIS patients [2].

Of course, physical therapy may not work for all shoulder impingement syndrome patients. When patients fail to see positive changes in their conditions following conservative treatments, they may opt for arthroscopic surgical decompression [5]. However, surgical therapy can be avoided in many cases, given how exercise therapy often produces improvements on par with those exhibited following surgery [5].

Ultimately, the existence of effective, versatile, and noninvasive treatments to counter SIS suggests that patients can manage this debilitating condition with great success at a low cost.

References

[1] M. C. Koester, M. S. George, and J. E. Kuhn, “Shoulder impingement syndrome,” The American Journal of Medicine, vol. 118, no. 5, p. 452-455, May 2005. [Online]. Available: https://doi.org/10.1016/j.amjmed.2005.01.040.

[2] A. Kul and M. Ugur, “Comparison of the Efficacy of Conventional Physical Therapy Modalities and Kinesio Taping Treatments in Shoulder Impingement Syndrome,” The Eurasian Journal of Medicine, vol. 51, no. 2, p. 139-144, June 2019. [Online]. Available: https://doi.org/10.5152/eurasianjmed.2018.17421.

[3] I. K. Bolia et al., “Management Options for Shoulder Impingement Syndrome in Athletes: Insights and Future Directions,” Open Access Journal of Sports Medicine, vol. 12, p. 43-53, April 2021. [Online]. Available: https://doi.org/10.2147/OAJSM.S281100.

[4] I. E. A. F. El-Shewi, H. M. E. Azizy, and A. A. E. F. H. Gadalla, “Role of dynamic ultrasound versus MRI in diagnosis and assessment of shoulder impingement syndrome,” Egyptian Journal of Radiology and Nuclear Medicine, vol. 50, no. 100, p. 43-53, December 2019. [Online]. Available: https://doi.org/10.1186/s43055-019-0107-7.

[5] G. Nazari et al., “The effectiveness of surgical vs conservative interventions on pain and function in patients with shoulder impingement syndrome. A systematic review and meta-analysis,” PLoS One, vol. 14, no. 5, p. 1-22, May 2019. [Online]. Available: https://doi.org/10.1371/journal.pone.0216961.

[6] S. G. Ucurum et al., “Comparison of different electrotherapy methods and exercise therapy in shoulder impingement syndrome: A prospective randomized controlled trial,” Acta Orthopaedica et Traumatologica Turcica, vol. 21, no. 4, p. 249-255, July 2018. [Online]. Available: https://doi.org/10.1016/j.aott.2018.03.005.