Over the last 33 years in practice, the last 28 years have been working with elite, world-class, professional and Olympic medalists as well as the non-athlete. While we all have a host of modalities available to help the injured patient, one constant in my bag of tricks is low intensity pulsed or continuous ultrasound.

While many are familiar with the importance of Nitric Oxide in the human body, ranging from increasing one’s immune system as well as it’s anti-inflammatory response, not many are familiar with the increase of Nitric Oxide and eNO’s (endothelial Nitric Oxide Synthase) production associated with low intensity ultrasound either pulsed or continuous, depending on the acuteness of the injury.

While most use therapeutic ultrasound for it’s thermal effects of heating attributing vasodilation to the heat, not many are aware of the non-thermal effects associated with ultrasound in the form of acoustic streaming and cavitation. This is the process when the sound wave passes through the cellular cytoplasm and creates a fluid wave. As the fluid wave moves through the cell, the free floating structures such as the mitochondria, Golgi bodies, vacuoles, lysosomes catch a ride on this fluid wave. As they move through the cytoplasm, they create a wake in which there are gas bubbles consisting of Nitric Oxide. (1) Journal of Athletic Training 2002;37(3):293–299q by the National Athletic Trainers’ Association, Incwww.journalofathletictraining.org “Nonthermal Effects of Therapeutic Ultrasound: The Frequency Resonance Hypothesis” Lennart D. Johns As stated most attribute vasodilation to the thermal effect of ultrasound but it has been proven that NO is key in promoting vasodilation as well.

In the human body there are three pathways in which Nitric Oxide is created, each pathway demonstrating a different purpose for the same by-product, NO. The first pathway is nNOS or NOS 1 and stands for neuronal Nitric Oxide Synthase, it’s primary purpose is synaptic plasticity, iNOS or NOS2 is known as inducing Nitric Oxide Synthase and it’s primary purpose is immune, parasitic, anti-tumoral, and anti-inflammatory, eNOS or NOS3 is known as endothelial Nitric Oxide Synthase and its primary function is cardiovascular and anti-inflammatory. (2) Indian J Pediatr. 1998 May-Jun;65(3):333-45. Nitric oxide: biological role and clinical uses. Kannan MS1, Guiang S, Johnson DE.

While the primary focus of therapeutic ultrasound has been on the known thermal effects, there are numerous studies that demonstrate the increase of NO through the eNOS pathway when using LIPUS (low intensity pulsed ultrasound) as well as LICUS (low intensity continuous ultrasound). One such study states:

“nitric oxide release, intracellular calcium concentration, and endothelial nitric oxide synthase (eNOS) gene and protein expressions after ultrasound exposure were analyzed. It was found that ultrasound exposure did not change the cell proliferation, but it enhanced the release of nitric oxide and Ca2+ ions, and increased the eNOS activity. The induced phosphorylation of eNOS (Ser1177) by the ultrasound exposure was inhibited by the addition of N- [2-(p- bromocinnamylamino) ethyl]-5-isoquinoline sulfonamide (H89, a protein kinase A inhibitor), but not 2-(4-morpholino)-8-phenyl-4H-1- benzopyran-4-one hydrochloride (LY294002, a phosphoatidylinositol 3- kinase inhibitor). The induced phosphorylation of Akt (protein kinase B, Ser473) by the ultrasound exposure was inhibited by the addition of LY294002, but not by the presence of H89. The results also applied to bovine carotid artery endothelial cells (BAECs) exposed to ultrasound at a larger intensity (68 mW/cm2). The above experiments suggested that low-intensity ultrasound might promote eNOS activity of endothelial cells via the phosphatidylinositol 3-kinase/Akt/protein kinase A signaling pathway. This may have implications on the therapeutic effect of ultrasound in tissue repair.”

(3) Shan-hui Hsu, Tsung-Bin Huang, and Kuan-Pu Wang, Biomed. Eng. Appl. Basis Commun. 22, 367 (2010) LOW-INTENSITY ULTRASOUND INCREASES THE ENDOTHELIAL NITRIC OXIDE SYNTHASE (eNOS) EXPRESSION OF ENDOTHELIAL CELLS POSSIBLY VIA THE PHOSPHATIDYLINOSITOL 3-KINASE/AKT/PROTEIN KINASE A SIGNALING PATHWAY

As a sports chiropractor, ultrasound and pulsed ultrasound, along with soft-tissue mobilization, movement therapy and chiropractic adjustments have been a big part of my regime in working with and helping athletes and non-athletes perform to their optimum.

Authored by: Rick Fox, DC

Author’s Bio

Dr. Rick Fox a 1984 graduate has been focusing his chiropractic practice on sports care and movement therapy. He started his journey working with athletes from the AVP (Association of Volleyball Professionals) and the WPVA (Women’s Professional Volleyball Association in the mid to late 1980’s. This created a journey where Dr. Fox would work at the Soft Tissue Center in Los Angeles, focusing on soft tissue therapy and rehabilitation with Olympic Medalists from the USA and Jamaican Track and Field teams, as well as athletes from the NHL, NFL, MLB, Body Builders, Weight lifters and then on to his own private practice in Arcadia, CA.

After many years of working with athletes, Dr. Fox founded the medical team for the Los Angeles Derby Dolls, an all women’s banked track roller derby league, in 2006. This led to his being the only chiropractor for the World Cup 1 & 2 of Roller Derby in Toronto, Canada and Dallas TX., respectively. His experience with the athletes in roller derby led to his creating and designing Second Knee, a unique knee brace designed after anatomy to stabilize, support and protect the knee. This led to the formation of his company, Dynamic Bracing Designs, LLC, where he is CEO and continues to dabble with inventing health care products for the betterment of his and other patients.

For fun, Dr. Fox enjoys playing with his dogs, playing guitar, organic gardening/farming to stay connected with the Earth and Tai Chi/Chi-Gong for balance, energy and breath.