Effects of Instrument Assisted Soft Tissue Mobilization on Physiological and Structural Properties of Human Skeletal Muscle

Abstract

INTRO Instrument Assisted Soft Tissue Mobilization (IASTM) is a popular treatment technique to reduce pain, help improve functional range of motion, and corresponding functional task completion. It has been reported both anecdotally and through controlled-clinical trials to evoke acute changes in skeletal muscle physiology through a variety of proposed mechanisms. However, the efficacy of IASTM has been called into question particularly as it pertains to its ability to improve skeletal muscle and connective tissue pathologies relative to traditional therapies including: stretching, light exercise, and therapeutic ultrasound. The purpose of this three-study investigation was to elucidate the effects of IASTM on human skeletal muscle as well as to examine possible mechanisms of change. METHODS To examine the efficacy of IASTM we designed three experiments. The first experiment tests the effects of IASTM on IL-6 and TNF-α cytokine expression in human skeletal muscle using Bergstrom needle muscle biopsies. Pro-inflammatory cytokines were of interest as they have been suggested to mediate positive outcome measures associated with IASTM. The second investigation was designed to examine the dose response in the presence of two different forces being administered. This study was largely designed as a follow up of an IASTM dose response experiment that was carried out in rodents. The final investigation was designed to examine the effects of IASTM on the architecture of skeletal muscle using diagnostic ultrasound. For this investigation both hamstrings range of motion restricted and age appropriate controls were used to examine if IASTM only elicits benefit in pathological tissue. RESULTS Results from this multi-study examination of the effects of IASTM have suggested that IASTM may not be the most αefficacious treatment available for degenerate soft-tissue. Our three investigations found no changes in MTS, PROM, MVC-PT, myokine expression, perception of functional ability as measured by the PFAQ, muscle quality (echo intensity), pennation angle or hip ROM. DISCUSSION The results from these three investigations suggest IASTM may not be efficacious especially when compared to more cost effective self-therapies including stretching and light exercise. However, the current investigations at hand were limited by sample size and the fact that two of the investigations were carried out in non-pathological tissue. Literature review reveals that IASTM can elicit change in degenerate muscle tissue through a fibroblast mediated pathway. Future investigations should use larger sample sizes and special populations including older adults and adults suffering from chronic tendinopathy.