A single session of trigger-point pressure release on latent soleus myofascial trigger points resulted in an immediate and significant improvement in ankle range of motion, according to recent research.

The study, “The immediate effect of soleus trigger point pressure release on restricted ankle joint dorsiflexion: A pilot randomised controlled trial,” involved 20 healthy volunteer participants. Five men and 15 women, with a mean age of about 22 years, composed the study population.

A screening process took place to ensure each subject had a restriction in active ankle dorsiflexion, as well as the presence of active and latent myofascial trigger points in the soleus muscle. These subjects were then randomly assigned to either the intervention group, which received a session of trigger-point pressure release, or the control group, which received no treatment.

The trigger-point pressure release used in the intervention group employs the barrier release concept. Subjects were in the prone position with both legs extended during the session. The researcher slowly applied increasing pressure with the thumb on the soleus myofascial trigger point, which had been marked prior to the session, until the first increase in tissue resistance was felt, indicating the barrier had been reached. The researcher then maintained the same pressure until there was a release in muscle tension beneath the palpating thumb.

“This process was repeated for approximately 60 seconds for each taut band identified,” state the study’s authors. “The intervention was three minutes, if all three [myofascial trigger points] were identified for treatment.”

In order to help standardize the study, subjects in both the intervention and control groups were placed in the prone position, with both knees extended bilaterally, for a total of five minutes.

The outcome measure for this pilot study was active ankle dorsiflexion range of motion. Three measurements were taken to calculate the mean range of motion for each participant, using a goniometer. This occurred before and after the intervention or control sessions.

Results of the research revealed a mean increase of 3.3 degrees in active ankle dorsiflexion range of motion among subjects in the group immediately after a single session of trigger-point pressure release. Participants in the control group, however, showed a slight decrease in active ankle dorsiflexion range of motion after spending five minutes in the prone position with both knees extended bilaterally.

“This study has indicated that a single treatment of [trigger-point pressure release] has shown an immediate, significant increase in active ankle dorsiflexion,” conclude the study’s authors.

Authors: Rob Grieve, Jonathan Clark, Elizabeth Pearson, Samantha Bullock, Charlotte Boyer and Annika Jarrett.

Sources: Department of Allied Health Professions, School of Health and Social Care, Faculty of Health and Life Sciences, University of the West of England, Glenside Campus, Blackberry Hill, Bristol, United Kingdom. Originally published in the Journal of Bodywork & Movement Therapies (February 2010).