Shoulder impingement syndrome (SIS)

Shoulder impingement syndrome (SIS) is a musculoskeletal condition in which the tendons or bursa in the subacromial space `rub` (impinge) against the acromion causing irritation and pain.

Structural differences in the 1) supraspinatus outlet and 2) acromial size & shape can cause impingement (Deberardino, 2015). 

Non-outlet impingement also can occur with 1) loss of normal humeral head depression from either a large rotator cuff tear or weakness in the rotator cuff muscles from a C5/C6 neural segmental lesion or a suprascapular mononeuropathy or 2) due to thickening or hypertrophy of the subacromial bursa and rotator cuff tendons (Deberardino, 2015). 

Studies such as Michener et al. (2004), Schröder et al. (2001), Faber et al. (2006) and Van der Windt et al. (1995) suggest that SIS is the most common cause of shoulder pain. 

Today, we are going to look at a study by Kolber et al. (2014) who examined `shoulder impingement in recreational weight trainees` with the following questions in mind.

1) Can we identify any common movements done by athletes with SIS?
2) Can we identify movements done by the healthy athletes that could prevent SIS?

Kolber et al. (2014) found that there was two exercises highly correlated with shoulder impingement; 1) lateral deltoid raises and 2) upright rows. However, they also found one group of exercises that reduced the risk of developing SIS, strengthening the external rotators of the shoulder. This is absolutely logical as both the lateral deltoid raises and upright rows are performed with the elbow at (or in some cases above - not preferable) shoulder height with internal rotation of the shoulder, both of these combined decrease the subacromial space and increase the likelihood of impingement, whereas the external rotators of the shoulder prevent possible tight / overactive internal rotators pulling shoulders into `rounded` or thoracic kyphosis which can lead to a reduced subacromial space; therefore maintaining muscle balance is essential. 

With the correct technique, sufficient shoulder mobility / stability and progressive overload the lateral deltoid raise and upright row are acceptable and effective exercises. My lecturer once said: "There are no such thing as a bad exercise, just inappropriate ones." 

Are these exercises appropriate for you, your clients or patients?

Original source: http://breakingmuscle.com/…/research-provides-new-insights-…

REFERENCES:
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Deberardino, (2015): http://emedicine.medscape.com/article/92974-overview#a7

Faber et al. (2006). Treatment of impingement syndrome: a systematic review of the effects on functional limitations and return to work. http://www.ncbi.nlm.nih.gov/pubmed/16705497

Kolber et al. (2014). Characteristics of shoulder impingement in the recreational weight-training population. http://www.ncbi.nlm.nih.gov/pubmed/24077379

Michener et al. (2004). Effectiveness of rehabilitation for patients with subacromial impingement syndrome: a systematic review. http://www.ncbi.nlm.nih.gov/pubmed/15162102

Schröder et al. (2001). Open versus arthroscopic treatment of chronic rotator cuff impingement. http://www.ncbi.nlm.nih.gov/pubmed/11409550

Van der Windt et al. (1995). Shoulder disorders in general practice: incidence, patient characteristics, and management. Annals of the Rheumatic Diseases, 54(12), p.959. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1010060