Myofascial Trigger Points in Shoulder Muscles
In my writings, I’ve frequently mentioned myofascial pain and trigger points (first mention is in referred shoulder pain post). In fact, much of the Swimmer’s Shoulder System and the work in progress Core Training for Swimmers focuses on myofascial trigger points. Personally, I’ve studied the research on trigger points and feel the research is quite vague on the effectiveness of treating myofascial trigger points in the shoulder. However, from personal experience, I feel the research poorly categories those with myofascial trigger points. For example, if someone has a presentation of inflammation in their shoulder, I’m not suggesting myofascial releases. Assuming everyone needs the same treatment for an injury is one major dilemma and pitfall of research, much like the swimming, an individualized approach of rehabilitation yields the greatest improvement. Nonetheless, understanding the influence of myofascial on shoulder pain can help determine the overall effectiveness and perhaps determine which people will benefit most from a myofascial treatment approach.
Background of Myofascial Trigger Points
Studies have found a high prevalence of muscles containing active and latent Myofascial Trigger Points (MTrPs) with high local mechanical pain sensitivity and referred pain in patients with chronic non-traumatic shoulder pain (Alburquerque-Sendin and others 2013; Bron et al., 2011b; Fernandez-de-las-Penas and others 2012; Ge and others 2006; Ge and others 2008). MTrPs are described as local points, highly sensitive to pressure causing characteristic referred sensations, pain, muscle dysfunction and in some cases even sympathetic hyperalgesia (Ge and others 2006; Simons and others 1999).
MTrPs may be classified as active or latent. Active MTrPs are characterized by the presence of clinical pain and constant tenderness, preventing full lengthening and leading to weakening of the muscle. Diagnostically, active MTrPs refer to patient-recognized pain upon compression and mediate a local twitch response in muscle fibers when adequately stimulated. When compressed, active MTrPs produce referred motor phenomena and often autonomic phenomena, generally in its pain reference zone. In contrast, latent MTrPs are clinically quiescent with respect to spontaneous pain, and are painful only when palpated. A latent MTrP may have all the clinical characteristics of active MTrP, always with a taut band that increases muscle tension and restricts range of motion.
Sergienko (2015) performed a literature review on the effectiveness of myofascial treatments on MTrPs (if you aren’t familiar with systematic reviews, please review this). Here is what the found:
Myofascial Trigger Points in Shoulder Muscles
MTrP palpation is a useful and reliable tool in diagnosing myofascial pain in patients with non-traumatic shoulder pain. Studies have shown a significant greater number of active MTrPs on the painful shoulder side. In contrast, no significant difference was found in the number of latent MTrPs between painful and non-painful shoulder muscles. Active MTrPs were most prevalent in the infraspinatus, upper trapezius and levator scapulae muscles.
The effect of MTrPs on shoulder muscle function was evaluated in four observational studies. Reduced muscle strength, accelerated muscle fatigue and simultaneous overloading active motor units were found in subjects with latent MTrPs.
Summary of Myofascial Trigger Points in Shoulder Muscles
This review suggest MTrPs is a common finding in patients with shoulder complaints. This is likely why the Swimmer’s Shoulder System has helped many swimmers prevent (as MTrPs are likely common in swimmers due to overuse) and rehab from shoulder discomfort. Also, ignoring the influence of MTrPs may be why traditional programs are not effective in improving strength and perhaps preventing swimmer’s shoulder (Hibberd 2012).
Not sure if working on MTrPs is worth the time? Just try doing a self myofascial release (SMR) on your infraspinatus for 3 minutes. First, move your arms around like you’re swimming, doing internal rotation and all kinds of motions, then do 3 minutes of SMR, and re-check your shoulder motion…you’re welcome!
- Sergienko S, Kalichman L. Myofascial origin of shoulder pain: A literature review. Sergienko S, Kalichman L. J Bodyw Mov Ther. 2015 Jan;19(1):91-101. doi: 10.1016/j.jbmt.2014.05.004. Epub 2014 May 15.
By Dr. G. John Mullen received his Doctorate in Physical Therapy from the University of Southern California and a Bachelor of Science of Health from Purdue University where he swam collegiately. He is the owner of COR, Strength Coach Consultant, Creator of the Swimmer’s Shoulder System, and chief editor of the Swimming Science Research Review.