In a recent study, researchers confirmed massage therapy results in significant improvements in posterior shoulder tightness. The researchers also found three factors linked to less improvement for this particular condition: longer duration of symptoms, higher functional limitation and less posterior deltoid tightness.
The study, “Effects and predictors of shoulder muscle massage for patients with posterior shoulder tightness,” involved 52 people diagnosed with posterior shoulder tightness.
Subjects included in the study showed glenohumeral internal rotation range-of-motion (ROM) limitation of at least 10 percent, when compared to the sound shoulder. They also showed at least 10 percent more posterior shoulder tightness, based on cross-chest adduction, when compared to the sound shoulder.
The main outcome measure for the study was glenohumeral internal ROM. For assessment, each subject was in a prone position. The subject’s arm was passively moved to the cessation of movement of internal rotation, with the arm held by the tester in 90 degrees abduction.
“The recorder, who was blinded to group allocation, placed a hand-held goniometer with two rams parallel to the forearm and trunk, respectively, and documented glenohumeral internal rotation ROM,” state the study’s authors. “During the test, the scapula was palpated at the lateral border and stabilized by hand.”
A second outcome measure was muscle tightness, assessed with a computerized myotonometer, which measures the transverse tightness of muscles by quantifying the amount of tissue displacement compared to constant applied pressure as a probe is pushed down onto the muscle and underlying tissue.
A third outcome measure was functional disability, as measured by the self-reported Flexilevel Scale of Shoulder Function. For this outcome measure, subjects who showed an improvement of 20 percent or more were categorized as responsive, whereas those who showed an improvement of less than 20 percent were categorized as nonresponsive.
Each of these outcome measures was assessed at baseline, before the start of the intervention phase and again four weeks later, after the intervention ended. For the four-week intervention phase, participants were randomly assigned to either the massage group or the control group.
Those in the massage group received two sessions per week for four weeks. The massage focused on the posterior deltoid, infraspinatus and teres minor of the affected shoulder, with about six minutes spent on each muscle for a total of 18 minutes per session. According to the researchers, the massage for each muscle consisted of three minutes of petrissage and three minutes of rolling of the soft tissues.
Subjects in the control group received 10 minutes of light hand touch on the same three muscles of the affected shoulder, two times a week for four weeks.
Results of the research revealed a significant increase in overall mean internal rotation ROM for the massage group. The massage group also showed a significant improvement in overall mean functional disability and a significant decrease in overall mean muscle tightness for all three muscles.
Among the subjects in the massage group, 21 were classified as responsive and eight were classified as nonresponsive, according to the results of the Flexilevel Scale of Shoulder Function. A statistical analysis of the subjects showed the nonresponsive subjects had longer duration of symptoms, more limited shoulder function and less posterior deltoid tightness.
“Muscle tightness reduction in the posterior shoulder contributes to improvement of glenohumeral internal rotation ROM after four-week massage,” state the study’s authors. “Additionally, less duration of symptoms and higher functional status of the subject can predict the effective massage treatment.”
Authors: Jing-Ian Yan, Shiau-yee Chen, Ching-Lin Hsieh and Jiu-jenq Lin.
Sources: School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan. Originally published in 2012 in BMC Musculoskeletal Disorders, 13(46).