Elite swimmers with and without unilateral shoulder pain: mechanical hyperalgesia and active/latent muscle trigger points in neck-shoulder muscles Hidalgo-Lozano A, Fernández-de-Las-Peñas C, Calderón-Soto C, Domingo-Camara A, Madeleine P, Arroyo-Morales M. Scand J Med Sci Sports. 2011 May 12. doi: 10.1111/j.1600-0838.2011.01331.x. https://www.ncbi.nlm.nih.gov/pubmed/21564310 Shoulder pain occurs frequently in swimmers, however the source of the shoulder pain is not often known. Many believe that shoulder laxity or instability may be a contributing factor, while others feel it may develop from chronic tendinopathy, and finally others suggest that altered scapular muscular control can lead to shoulder pain. There has been evidence demonstrating that swimmers present with alterations in the position and motion of the scapula. These adaptations can increase muscular tension thereby creating active trigger points, which will cause shoulder pain and possible worsen the muscle tension, creating a vicious cycle. However, the presence and sensitivity of trigger points have never been examined in swimmers with shoulder pain. The authors of this study examined the presence and pressure pain thresholds (PPT) of active trigger points in the neck and shoulder muscles of elite swimmers (shoulder-pain group and pain-free group) and a non-swimming control group. The muscles assessed included: levator scapulae, sternocleidomastoid, upper trapezius, infraspinatus, scalene, subscapularis and tibialis anterior. The presence of trigger points was determined by a blinded assessor with over 8 years of experience with trigger point diagnosis. They found that swimmers regardless of group had significantly lower PPT in all muscles compared with non-swimming controls, suggesting a hypersensitivity to pain. There were no differences between swimmers with and without shoulder pain. Swimmers with shoulder pain had a significantly higher number of active trigger points compared to those without shoulder pain. Based on the results it seems that swimmers have a hypersensitivity to pain regardless of having shoulder pain. Swimmers were also found to have an increased presence of both latent and active trigger points, although the swimmers with shoulder pain had more active trigger points. The larger number of trigger points may partially explain their shoulder pain. This is an interesting finding with clinical applications to not only swimmers but all overhead athletes. It would be interesting if they also examined scapular position and motion in these swimmers. This would help to determine if there is an association between scapular dyskinesis and trigger points, along with the hypersensitivity of pain. When scapular dyskinesis develops it can place increased tension or strain on the posterior scapular stabilizing muscles. With overuse this increased strain may lead to the creation of an active trigger point. We commonly see these trigger points at the superior angle of the scapula (origin of the levator scapulae) and the muscle belly of any of the trapezius divisions in overhead athletes. Once these trigger points become active it will cause considerable pain during functional motions. Continued research in this area will help discover more about the causes of shoulder pain, which in return may lead to better treatment options. Soft tissue mobilizations may be a great way to treat trigger points in overhead athletes; however we need to keep in mind that we are only treating the symptoms. We need to find the source of these trigger point, whether it be scapular dyskinesis, shoulder instability, or overuse. In my experience treating scapula dyskinesis will dramatically improve shoulder pain and reduce the presence of active trigger points. What is everyone’s experience with this? Written by: Stephen Thomas Reviewed by: Jeffrey Driban
To make this more clinically applicable, the next step needs to be taken.
Are trigger points a valid indicator or symptom of swimmers shoulder or just a concurrent finding. More importantly if they are treated does this improve pain and function.
Also swimming volume should be tracked in addition to scapular measures with between group comparisons.
Amy thanks for the comment. One interesting part of their findings was that when an active trigger point was identified the participants described the pain during the palpation of the trigger point was the same pain they experience during swimming.
I completely agree that a study needs to be completed examining the effectiveness of various types of treatments for trigger points and its effect on functional pain and outcome measures.
I agree also. As Paul Geisler noted on the patellar tracking post (May 6th) it will be important for sports medicine research to start doing more longitudinal studies to answer questions like 1) are active trigger points causing more shoulder pain or scapular dyskinesis, 2) does scapular dyskinesis lead to more active trigger points, or 3) are these just concurrent findings related to other issues. It is also important for our field to encourage and seek more randomized controlled trials (or comparative effectiveness studies) to see if treating trigger points provides better treatment effects than other treatment approaches. It would also be interesting to see validity data as you suggested (e.g., sensitivity and specificity of active trigger points and shoulder pain). This study is a nice first step justifying more research like you suggested.
I suspect in the coming years we will see more clinical studies fulfilling these clinical needs.
Thanks for the comment,