Therapeutic ultrasound refers generally to any type of ultrasonic procedure that uses ultrasound for therapeutic benefit.
Ultrasound passes through human tissue where it is the main source of its observed biological effect.
The ultrasound within tissue consists of very high frequency sound waves, between 800,000 Hz and 20,000,000 Hz, which cannot be heard by humans.
Evidence exists that ultrasound is more effective than placebo treatment for treating patients with arthritis pain, musculoskeletal injuries and for promoting tissue healing.
Therapeutic ultrasound (TUS) is the application of ultrasound energy for the treatment of various medical conditions, distinct from its use in diagnostic imaging.
Ultrasound — or ultrasonography — is an imaging technique used not just during pregnancy but also for many medical procedures. Ultrasound physical therapy is a branch of ultrasound, alongside diagnostic ultrasound and pregnancy imaging. It’s used to detect and treat various musculoskeletal issues you may have including pain, tissue injury, and muscle spasms.
Low-power ultrasound, typically around 1 MHz, is commonly used in physical therapy to treat conditions such as tendinitis and bursitis.
Low-power ultrasound modality can enhance tissue repair by increasing cell permeability, promoting ion and molecule flow, and modulating cell signaling pathways, collectively facilitating the repair of injured tissues.
High-power ultrasound applications include high-intensity focused ultrasound (HIFU), used for tissue ablation in conditions such as uterine fibroids and certain cancers.
High-power ultrasound generates localized heating and mechanical effects, leading to cell death in targeted tissues.
Therapeutic ultrasound uses include lithotripsy for kidney stone fragmentation, phacoemulsification for cataract removal, and enhancing drug delivery through mechanisms such as sonophoresis and sonoporation.
Therapeutic ultrasound can cause adverse effects like burns or hemorrhage if not properly managed.
Therapeutic ultrasound is a type of physical therapy modality
It uses high-frequency sound waves to treat various musculoskeletal conditions.
It is a non-invasive treatment method that can provide pain relief and promote tissue healing.
An ultrasound machine generates high-frequency sound waves that are applied to the skin through a handheld wand.
Sound waves penetrate into the tissues, causing vibration at a molecular level.
This vibration generates heat within the tissues, which can help increase blood flow, relax muscles, and reduce pain and inflammation.
Therapeutic ultrasound is commonly used to help manage conditions such as tendonitis, muscle strains, joint stiffness, and soft tissue injuries.
It is usually a painless and gentle treatment.
The duration and intensity of the ultrasound treatment is adjusted based on the individual’s condition and response to the therapy.
Relatively high power ultrasound can break up stony deposits or tissue, accelerate the effect of drugs in a targeted area, assist in the measurement of the elastic properties of tissue, and can be used to sort cells or small particles for research.
Focused high-energy ultrasound pulses can be used to break calculi such as kidney stones and gallstones into fragments small enough to be passed from the body without undue difficulty (lithotripsy).
Focused ultrasound sources may be used for cataract treatment by phacoemulsification.
Ultrasound can ablate tumors or other tissue non-invasively, by High Intensity Focused Ultrasound (HIFU), also called focused ultrasound surgery. This procedure uses generally lower frequencies than medical diagnostic ultrasound (250–2000 kHz), but significantly higher time-averaged intensities.
The treatment is often guided by Magnetic Resonance Imaging (MRI); the combination is then referred to as Magnetic resonance-guided focused ultrasound.
Enhanced drug uptake using acoustic targeted drug delivery, can be used to deliver chemotherapy to brain cancer cells and various drugs to other tissues.
These procedures generally use high frequency ultrasound (1–10 MHz) and a range of intensities (0–20 W/cm2).
Ultrasound has been used to trigger the release of anti-cancer drugs from delivery vectors including liposomes, polymeric microspheres and self-assembled polymeric.
Ultrasound is essential to the procedures for ultrasound-guided sclerotherapy and endovenous laser treatment for the non-surgical treatment of varicose veins.
Liposuction can be assisted by ultrasound.
Phonophoresis is a form of soft tissue treatment that involves the use of ultrasound combined with medication gels and will utilize ultrasound waves to enhance drug delivery to the injured area.
Effects of US: increase in blood flow in the treated area.
Decrease in pain from the reduction of swelling and edema[citation.
Gentle massage of muscle tendons and/ or ligaments in the treated area because no strain is added and any scar tissue is softened.
The main effects of therapeutic ultrasound are: thermal and non thermal effects.
Thermal effects are due to the absorption of the sound waves.
Non thermal effects are from cavitation, microstreaming and acoustic streaming.
Cavitational effects result from the vibration of the tissue causing microscopic bubbles to form, which transmit the vibrations in a way that directly stimulates cell membranes, and physical stimulation appears to enhance the cell-repair effects of the inflammatory response.
Ultrasound is applied using a transducer or applicator that is in direct contact with the patient’s skin.
Gel is used on all surfaces of the head to reduce friction and assist transmission of the ultrasonic waves.
Therapeutic ultrasound in physical therapy is alternating compression and rarefaction of sound waves with a frequency of 0.7 to 3.3 MHz.
The maximum energy absorption in soft tissue occurs from 2 to 5 cm.
Intensity decreases as the waves penetrate deeper.
The waves are absorbed primarily by connective tissue: ligaments, tendons, and fascia and also scar tissue.
Ultrasound aims to stimulate specific muscles beneath the skin, and provides a way for physical therapists to better locate superficial musculature.
Ultrasound may be used for treatment include ligament sprains, muscle strains, tendonitis, joint inflammation, plantar fasciitis, metatarsalgia, facet irritation, impingement syndrome, bursitis, rheumatoid arthritis, osteoarthritis, and scar tissue adhesion.
No evidence to support the use of ultrasound for the treatment of low back pain.
Ultrasound therapy demonstrates that therapeutic ultra sound is effective in improving pain, function, and cartilage repair in knee osteoarthritis.
A meta-analysis of low-intensity pulsed ultra sound on knee osteoarthritis a significant effect on pain reduction and knee functional recovery was demonstrated.
Ultrasound used for calcific tendonitis has a positive short term effect, but for the long term, there was no significant difference with ultrasound use.
Therapeutic ultrasound can provide pain relief, in the short-term for calcific tendinitis
In five small placebo‐controlled trials, no support for the use of ultrasound in the treatment of acute ankle sprains and the potential treatment effects of ultrasound appear to be generally small and of probably of limited clinical importance, especially in the context of the usually short‐term recovery period for these injuries.
Therapeutic ultrasound reported to have beneficial effects in sports injuries with pain relief, edema control, and range of joint motion, possibly by increasing pain thresholds, collagen extensibility, reducing edema, and therefore inflammation, muscle spasms, and joint stiffness.
A meta-analysis found ultrasound therapy is effective in reducing pain, increasing ROM, and reducing WOMAC functional scores in patients with knee osteoarthritis.
Therapeutic ultrasound has not shown any significant improvement for chronic low back pain, chronic neck pain, and hip pain in combination with other physiotherapeutic techniques.
The most conclusive evidence to support therapeutic ultrasound use is seen with its use in patients with knee osteoarthritis.
Knee osteoarthritis affects approximately 250 million people worldwide.
In a review of 15 studies, patients who received ultrasound treatments were compared to those who received a placebo treatment.
Therapeutic ultrasound significantly relieved pain, increases range of motion, and functional scores in patients with knee osteoarthritis when compared to the placebo group.
Therapeutic ultrasound is a safe non-pharmalogical treatment option that may provide additional pain relief as well as functional improvement when used secondarily to therapy in patients with knee osteoarthritis.
Low-intensity ultrasound could be its potential to disrupt the blood–brain barrier for drug delivery.
Ultrasound has been shown to contribute to improvement of muscular strength of the forearm muscles and humerus muscles and an increase in range of motion in the elbow joint in flexion and outward rotation when accompanied with therapeutic exercise as well as a reduction in pain in men ages 30-40 with tendinitis.