Accepted evidence and new considerations in instrument-assisted soft tissue mobilization
There is little debate regarding the use of IASTM (instrument-assisted soft tissue mobilization) techniques being effective, but there is some good discussion as to why are they effective and how to use them. There are some not-so-obvious reasons why the tools are effective and why you might choose various methods.
Eastern medicine roots
IASTM has ancient roots in Eastern medicine and is commonly known as Gua-Sha in the Eastern medicinal culture. Their natural tools have been used for centuries with great effectiveness. They come in a variety of sizes and in three common materials.
The heavier tools were made of jade, a national stone of China, so precious that they line the Olympic medals in jade when they host the games. They also have lighter tools made of either animal bone or horn. These tools have a very different feel, as the heavier stone provides a feel for the deeper tissues like muscle. The tools made of bone or horn are more porous and provide a more superficial feedback to the user, for tissues like the skin and fascial layers.
As tools have popularized in the U.S., most are made of metal and are generally used in a deep application. This application is often thought to break up scar tissue or cause an inflammatory response to the local tissue. This concept of breaking up scar tissue has been heavily researched by academics around the world and found to require substantial amounts of force exceeding 2,000 pounds per square inch (Chandry et al.). This tremendous force is quite painful and, in most cases, intolerable. The reality that we can actually break up adhesions or break up scar tissue is quite slim.
Improve glide, reduce pain
Evidence is stronger to support the idea that we can improve glide between fascial layers. For this to occur, much less force is needed, much less pain is incurred, and strong evidence of decreased pain and increased function are associated with improved fascial glide. (Stecco et al., Langevin et al., Bove et al.)
This is the mechanical mechanisms at work. We can’t deny when we touch someone that there is a sensory and therefore neurological impact. As clinicians we know that how we touch someone tremendously influences how they feel, how they trust us and how they move. The tools give us tremendous flexibility as to how we apply this stimulus. We can perform rapid oscillations, slow prolonged holds, light feathering techniques, or as are commonly done, gliding strokes to improve local tissue glide.
Oscillation for stimulation
With these methods of touch we can directly influence the nervous system and our clients’ response. Evidence shows that rapid oscillating movements tend to stimulate the pacinian corpuscle, resulting in a heightened awareness and motor response. We know that rapid oscillation or vibration stimulates motor output in research and in practice.
Have you ever watched a 100-meter sprint at an elite track event? I’ve been fortunate to serve as a medical provider at multiple Olympic Games and world-class events, and there is nothing like the 100. Watch the racers prior to the start — it is so consistent across the board and around the world. Before they enter the blocks, they shake their legs, do some quick jumps, then slap their thighs and legs — all rapid motions designed to prime them for speed or maximal motor control. We can use oscillation in the same way over a muscle that is stubborn to fire or so-called weak.
Some clinical examples of this might be applying oscillation about the rotator cuff to improve stability of the shoulder. I find it works well clinically around the feet, specifically the posterior tibialis for arch control and support in gait and midstance.
Slow your hold
Other common neurological changes we see can be found with slow, long holds, which have the opposite effect of oscillations. Slow holds tend to cause a calming effect, or decrease motor control response, helping muscles relax (Van den Berg and Capri).
The receptor thought to be responsible for this response is the Ruffini receptor. This can be a great way to relax muscle tissue around stiff areas. Think trigger-point release in the para scapular region, or tight quad following a knee surgery or trauma, and difficult regions like the pec minor, psoas and piriformis. These regions are commonly tense and hold tension in the body. Using slow and sustained pressure can make a meaningful impact in releasing this tension.
Feathering technique
One concept that was difficult for me to accept, but that has since yielded outstanding results, is a method called feathering. This is a light stroke on the surface of the skin that can be extremely effective in reducing pain.
The concept of pain reduction is stemmed in the idea of threat reduction. If we can reduce threat, we can often reduce pain. We know pain is a signal the brain interprets as something is unsafe. This can happen in an unknown environment, where lack of proprioception or awareness is present. This can happen with something sharp touching you, causing you to pull away from the threatening stimulus.
Feathering is a very light and inviting technique that allows you to apply a light touch, like a feather, while communicating with your client at the same time. Asking them what they feel, and what part of the body you are touching, and what side of the body you are touching. This comforting touch and increased proprioceptive awareness can lead to less threat and fear, and therefore less pain. When teaching IASTM, I remind students to always be the safest thing in the room. Safety means comfortable touch and a strong knowledge base to win clients’ trust and calmness.
A patient’s limiting factor
As you consider IASTM for your client, ask yourself: What is their limiting factor? Is it pain, mobility, stability, or strength and power?
If it is pain-limiting, consider a feathering strategy to calm the nervous system and bring more awareness to the region. If the limiting factor is mobility, then a traditional glide strategy may be most impactful. You could also consider a slow enduring pressure strategy to down-regulate the nervous system, causing muscle relaxation and the potential for more motion. If strength or stability limit the client’s performance, consider oscillations to produce more motor control and increased recruitment to improve muscle performance.
Re-train the brain
No matter what the limiting factor is and the strategy that you implement, the most important part is what you do after the treatment. Research and clinical experience strongly support that passive treatments are minimally effective, unless combined with more meaningful self-directed motion. This concept holds true with many modalities and most manual therapy forms.
If you apply a technique without movement or exercise to follow, the results are significantly less profound. We always, when appropriate, want to add meaningful movement or functional action after we perform a passive treatment. The body is a “use it or lose it” system. When we provide IASTM we open a window of opportunity for movement. We need to take that window and use it, so that the brain learns that a movement is safe and can use it again. Otherwise clients can return to bad habits and faulty patterns.
Always remember the body is a complete system and tissue does not live in a silo. All tissue has a nervous system and a brain connected to it. Let’s give that brain information and make it react and change.
TONY MIKLA, DPT, MSPT, CSCS, XPS, is a sports physical therapist and performance coach. His practice is dedicated to the improvement of his clients’ performance in life and on the field. Tony is a master instructor for RockTape and blogs at kimeperformance.com.
