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Updated: Jun 24, 2026

Clinical Efficacy of Small Needle Knife Therapy on Stage I-II Frozen Shoulder
Published on: November 17, 2023
Muscular load to the therapist's shoulder during three alternative techniques for trigger point therapy
Emily Kristen Smith1, Mary Magarey, Steve Argue
1School of Health Sciences, Division of Health Sciences, University of South Australia, North Terrace, Adelaide 5000, South Australia. Emily.Smith6@hotmail.com
Aim:
To compare the muscular load (level of muscle activity) to the shoulder during alternative approaches to trigger point therapy (TPT).
Method:
Massage therapy students (n=7) applied a predetermined level of force to an artificial contact surface. Changes in five pairs of superficial shoulder muscles (indicated by surface electromyography) were recorded while the student performed the single-arm technique (SAT), the double-arm technique (DAT) and the treatment-tool technique (TTT) using TriggerMate, a new treatment tool.
Results:
For the contact arm, muscle activity was significantly decreased using the TTT compared to the SAT (p<0.05) but was not significantly different between the TTT and DAT. For the non-contact arm, none of the test techniques led to significant differences in muscle activity.
Conclusions:
While there is evidence that the TTT decreases the muscular load to the shoulder of the contact arm, there is no indication of where this load is redistributed.
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