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  • Writer's pictureOwen Giroux

What is Instrument-Assisted Soft Tissue Mobilization (IASTM) and how does it work?

Updated: Nov 21, 2023

IASTM on the upper trapezius muscle

It's becoming more common for therapists to reach for manual assistive tools during treatment. As a Registered Massage Therapist and Personal Trainer, I've worked with therapists who believe in these tools and some who are far less persuaded by their claims. I've received training in IASTM, but am not convinced myself, however I do still reach for tools from time to time. It is becoming essential for us all to be advocates for our health, so I hope this article can clarify some things regarding the modality, and empower you to speak up to either request or turn down the tools if offerred.

Let's examine the benefits, risks, and common mistakes and confusions with IASTM.


What is IASTM and how can it help?

Intramuscular Soft Tissue Mobilization (IASTM) is a technique used in manual therapy, including registered massage therapy, to address soft tissue restrictions and promote healing. It involves the use of specialized tools to apply pressure and friction to the skin, muscles, and connective tissues. In British Columbia, registered massage therapists (RMTs) may use IASTM as part of their therapeutic approach, and many personal trainers reach for similar devices while working with clients.

IASTM is common in sports-related care, dealing with scar tissue, or in trying to free up restrictions in tissues that may be catching or pinching down on other structures.

Benefits of IASTM:

  1. Breakdown of Scar Tissue: IASTM is believed to help mobilize and free up scar tissue and adhesions in muscles and soft tissues, improving range of motion and reducing pain.

  2. Improved Blood Flow: The technique enhances circulation in the treated areas, promoting the delivery of oxygen and nutrients to the tissues. This is primarily through the release of histamine in the dermis from the mechanical agitation, yielding a superficial hyperemia (flushing and red-colouration) of the skin, having mild spill over effects below the skin to structures below.

  3. Increased Flexibility: IASTM can contribute to increased flexibility by addressing restrictions and tightness in the muscles and connective tissues.

  4. Pain Reduction: The treatment may help reduce pain by releasing tension and addressing trigger points in the muscles. Endorphins are also release from the painful technique and manual contact. The majority of the pain relief comes after the administering of the technique, as it is often uncomfortable if done in a classical style. Many argue that most pain relief stems from neurological pain modulation from the mechanical stimulus, much like your reflex to rub your leg if it hurts, or similar to the use of topical pain creams.

  5. Improved Tissue Function: By addressing soft tissue restrictions, IASTM aims to improve the overall function of muscles, tendons, and ligaments.

Why doesn't everyone do it, then? What are the risks?

IASTM is often not comfortable, nor even the first choice of enthusiastic patients for the same reason. Many therapists base their practice on fancy techniques, relying on the release of histamines and endorphins, and pain modulation to provide relief, with a healthy dose of placebo, too. Many critics disagree with this practice and advocate for a holistic and clinical approach to care, without disregarding the modality itself.

Risks of IASTM:

  1. Bruising and Discomfort: Some individuals may experience bruising or discomfort after IASTM, especially if the treatment is aggressive or if they have sensitive skin.

  2. Skin Irritation: Excessive pressure or improper technique may cause skin irritation. Practitioners should use caution to avoid abrasions or burns.

  3. Bruising: In rare cases, IASTM may lead to the formation of hematomas (bruises) if blood vessels are damaged during the treatment. This is often with aggressive, deeper scraping with the tools, and is rare if administered reasonably.

  4. Contraindications: IASTM may not be suitable for individuals with certain medical conditions, such as deep vein thrombosis, open wounds, or skin infections, poor healing, those on blood thinners, those with frailty or thin skin, or for anyone not fully consenting to a potentially irritating technique.

It's important to note that the effectiveness and safety of IASTM can vary based on the individual, the specific condition being treated, and the skill of the practitioner. Before undergoing IASTM or any other manual therapy, individuals should consult with a registered massage therapist or healthcare professional to ensure that it is appropriate for their specific situation. Practitioners should also be trained and certified in the use of IASTM techniques to minimize the risk of adverse effects.

For a deep clinical analysis and criticism of the modality, give this article a read ( from Taylor J. Laviolette, RMT

What's the nutshell?

IASTM is a neat technique that I do use with patients, although not often. I, like many therapists, have seen success with patients where other modalities proved ineffective. There is a large professional body of dedicated professionals using tools. Although some call them glorified thumb-savers for the therapists, they definitely have value in practice.

I would hesitate to say they offer a high value to risk ratio to most patients. I've found that using tools after a trigger point release or active release to an area can assist with kickback pain and relapse of an area. I've also seen fascial and neurological pain patterns resolve after a single treatment from what appeared to be fascial restriction along the nerve path. Cool things happen and that's important to mention!

Ultimately, you should do what you like and trust your body. If you're reading this article, you're clearly interested in health and self care, and you're already likely a better fit to try the modality than most. Give it a shot, but dont' be afraid to tap out! It shouldn't hurt, but discomfort is not uncommon.

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