Publications

Abnormal muscle stiffness is a potential complication after injury and identifying interventions that modify muscle stiffness may be useful to promote recovery. The purpose of this study was to identify the short-term effects of dry needling (DN) on resting and contracted gastrocnemius muscle stiffness and strength of the triceps surae in individuals with latent myofascial trigger points (MTrPs).

In this randomized controlled trial, 52 individuals received two DN treatment sessions to latent MTrPs and 50 individuals received two sham needling sessions. Resting and contracted muscle stiffness were assessed both at the treatment site and a standardized central site in the medial gastrocnemius head immediately post-treatment and one week after the last session.

There were significant group by time interactions for resting muscle stiffness at the site of the MTrP (p = .03), but not at the central site (p = .29). Post-needling between group comparison indicated that the DN group had significantly lower resting muscle stiffness at the site of the MTrP than the sham group after adjusting for baseline differences. There were no significant between group differences in contracted muscle stiffness or muscle strength. Identifying strategies that can reduce aberrant muscle stiffness may help to guide management of individuals with neuromuscular pain-related conditions.

Level of evidence: Therapy, level 2.

This study suggests that resting muscle stiffness of the gastrocnemius measured at the MTrP site is reduced approximately one week following an initial session of DN and immediately after a second session of DN. Resting muscle stiffness is also reduced in the gastrocnemius muscle in a relaxed state at a central site approximately one week after an initial session of DN. However, DN had no effect on muscle stiffness in a contracted state or on muscle strength in this study.