The Truth About Instrument Soft Tissue Mobilization: What It Is, How It Works, and Why It's Not About "Breaking Up Scar Tissue"

Have you ever seen those metal tools therapist use on people? Those tools are called instrument assisted soft tissue mobilization and they do a LOT more than you think!

Some people also commonly call this type of massage "scrapping" and is known by other terminology such as Graston Technique or Gua Sha. These are all forms of soft tissue massage, at AVION we use this to enhance our Sports Massage that is much more targeted treatment on injured areas as opposed to a therapeutic massage used for more wellness purposes.

Let’s dive into the science behind IASTM, clear up common myths, and explain how it actually promotes recovery.

What Is Instrument Assisted Soft tissue Mobilization (IASTM)?

IASTM involves the use of specially designed tools (often stainless steel or surgical-grade metal) to apply targeted pressure to the skin, fascia, and underlying soft tissue. It’s a modern evolution of traditional manual therapy techniques, offering precision and feedback that fingers alone can’t provide.

These tools allow clinicians to detect restrictions, facilitate tissue remodeling, and—most importantly—stimulate the nervous system to promote pain relief and improved mobility.

IASTM is rooted in the principles of fascial manipulation and modern neurophysiology. The tools are designed to conform to the contours of the body, allowing for effective targeting of problematic areas with less strain on the practitioner’s hands. As the instrument glides over tissue, it amplifies tactile feedback, helping clinicians identify areas of densification or dysfunction that may not be easily palpated by hand alone.

More than just a tool-assisted massage, IASTM provides mechanical stimulation that initiates a cascade of biological responses. These include local inflammation that promotes tissue remodeling, increased microcirculation, and—most critically—stimulation of the peripheral nervous system. This neurostimulatory effect can help downregulate pain signals, reduce muscle guarding, and improve neuromuscular control, contributing to enhanced mobility and faster recovery.

In essence, IASTM combines the diagnostic insight of palpation with the therapeutic benefits of targeted mechanical input, making it a powerful modality for restoring pain-free movement in active individuals.

The Big Myth: "Breaking Up Scar Tissue"

For years, the go-to explanation for IASTM was that it “breaks up scar tissue” or “releases adhesions.” While that language has been popularized in fitness and therapy circles, it doesn’t quite hold up under scientific scrutiny.

Current research shows that we’re not actually breaking apart fibrotic tissue with manual pressure alone—especially not with instruments. The pressure required to physically deform or break down scar tissue is far beyond what’s safe or even possible during a soft tissue session.

So what’s really happening?

Neuromodulation: The Real Mechanism

The true benefit of IASTM lies in neuromodulation—a neurophysiological process in which targeted mechanical stimulation of the skin, fascia, and underlying soft tissues sends afferent (incoming) sensory signals to the central nervous system. These inputs help recalibrate how the brain and spinal cord interpret pain, tension, and movement-related information, allowing the body to shift from a protective or guarded state into a more optimal, relaxed state of function.

When an IASTM tool glides over tissue, it activates specialized sensory receptors called mechanoreceptors, including Ruffini endings, Pacinian corpuscles, and Merkel cells. These receptors are sensitive to pressure, stretch, and vibration, and their stimulation leads to a cascade of neurochemical and biomechanical changes:

Pain is modulated through both spinal reflex inhibition (segmental modulation) and central descending pathways from the brain, reducing the intensity and emotional response to pain.

Muscle tone decreases as motor neurons receive altered input, leading to a reduction in involuntary guarding or protective tension.

Joint and movement perception improves, helping the body "re-learn" healthy movement patterns and reducing the sensation of stiffness or limitation.

Immediate gains in range of motion are often observed—not because scar tissue is broken down, but because the nervous system has shifted from threat detection to movement facilitation.

IASTM, then, is not about forcibly changing tissue with brute force. Instead, it’s about interacting with the nervous system—leveraging its adaptability to reprogram how the body perceives and moves. The result? Faster improvements in pain, flexibility, and function, especially when paired with movement-based therapies that reinforce these new, pain-free patterns.

Benefits of IASTM

✅ Improved mobility and range of motion

✅ Decreased muscle tone and guarding

✅ Pain reduction through non-invasive methods

✅ Enhanced circulation and lymphatic flow

✅ Faster recovery between training sessions or after injury

IASTM is especially helpful for:

• Chronic tightness or stiffness

• Post-surgical or post-injury recovery

• Tendinopathies (like tennis elbow or Achilles tendinopathy)

• Myofascial restrictions

How IASTM Fits Into Your Rehab Plan

At AVION Sports Rehab, we’re committed to using the most effective, evidence-based techniques to help active adults recover faster, move better, and stay pain-free. One technique that often sparks curiosity (and sometimes confusion) is IASTM, or Instrument Assisted Soft Tissue Mobilization.

IASTM is never a standalone service. We integrate it into a comprehensive treatment plan that includes movement-based therapy, corrective exercises, and client education. We use it when the nervous system needs a reset—when tissue feels “stuck” and motion feels limited.

It’s one tool in our toolbox, and when used with intention, it can significantly accelerate your return to pain-free movement.

Is IASTM Right For You?

If you’re an active adult struggling with pain, tightness, or movement limitations, IASTM might be part of the solution. Book a session with one of our clinicians to see if it’s a fit for your goals.

Ready to experience IASTM the right way? Visit www.avionpt.com to book your evaluation or ask us how this technique could help you move pain-free again.

References:

1. Cheatham SW, Baker RT, Kolber MJ. "Instrument Assisted Soft-Tissue Mobilization: A Commentary for Clinicians." Int J Sports Phys Ther. 2016;11(5):748-756.

2. Laudner K, Compton BD, McLoda T, Walters CM. "Acute effects of instrument assisted soft tissue mobilization for improving posterior shoulder range of motion in collegiate baseball players." Int J Sports Phys Ther. 2014;9(1):1-7.

3. Loghmani MT, Warden SJ. "Instrument-assisted cross fiber massage accelerates knee ligament healing." J Orthop Sports Phys Ther. 2009;39(7):506-514.

4. Seffrin-Nash E, Hitt JR, Paci JM. "The Effects of Instrument Assisted Soft Tissue Mobilization on Range of Motion and Pain: A Systematic Review." Int J Sports Phys Ther. 2020;15(5):813-825.