Ultrasound physiotherapyBy Nigel Chua
Most patients, when they hear about "ultrasound" treatment for their injuries, think of the imaging ultrasound used during pregnancy to see the baby's image on the screen.
That's the more common and familiar use of ultrasound, but we'd also like to share with you that there is a non-imaging, therapeutic form of ultrasound, This is used to treat:
- "soft tissues" like muscle injuries, tendon injuries, ligament injuries
- "hard tissues" like bone bruising, bone fractures.
In fact, research has shown that ultrasound treatment accelerates both soft tissue and hard tissue healing.
FIRST OF ALL, WHAT IS ULTRASOUND?
Therapeutic ultrasound machines that our senior physiotherapists use in our physio clinics produce specialize healing sound waves that create a healing effect on:
Because these healing ultrasound waves are beyond the upper limits of human hearing, we can't hear them whilst they're being effected.
The two most commonly used frequencies of sound waves are 1 MHz (megahertz) and 3 MHz, which determine how deep the sound waves go. We use 3 MHz for more superficial injuries and 1 MHz for deeper ones.
These ultrasound waves travel through the skin and get absorbed by the soft tissues and bones.
SO HOW DOES ULTRASOUND HELP IN HEALING?
For soft tissues such as tendons, cartilage, muscles and ligaments, there are two ways the therapeutic ultrasound waves work, which are:
- thermal (heating effect)
- non thermal (non heating effect).
High intensity continuous ultrasound can cause the tissues to have a heating effect.
This heating effect causes the surrounding blood vessels to expand, improving the blood circulation to that area. The heat also increases the metabolic rate of the cells of the soft tissues, increasing their healing capability.
This needs to be used cautiously, because in the event of acute (fresh) injuries to the soft tissues or bony tissues, using a heating element can increase the inflammation.
For acute injuries, low intensity pulsed ultrasound is preferred as it increases the cellular activity of the injured soft tissue and promotes a faster healing, without the detrimental effects of heating.
I FELT NOTHING DURING THE TREATMENT. DOES IT REALLY WORK?
During the treatment, patients typically will not feel much. The most that you may feel during a session is mild warmth.
EVIDENCE FOR ULTRASOUND
As for the efficacy of ultrasound therapy in the healing of soft tissues, there is unfortunately no conclusive consensus on its therapeutic effects.
Current research suggests that effective evidence based application of ultrasound is highly dependent on therapist knowledge and appropriate training in ultrasound application. This is why we only work with very experienced senior and principal physiotherapists in Phoenix Rehab physio clinics.
It remains a popular choice for physiotherapists, mainly due to the clinical effectiveness reported by many clients. Patients and doctors anecdotally report effectiveness in 50-75% of cases in which ultrasound physiotherapy is applied.
STRONG EVIDENCE FOR USE OF ULTRASOUND IN FRACTURE HEALING
There is very strong evidence in recent research to show that low intensity, pulsed ultrasound, started seven days after a diagnosed fracture of the bone, applied daily for one time of 20 minutes each time, can induce healing of the bones and reduces the healing time by 20-40%.
Should you wish to find out more about ultrasound and how It may help you, please feel free to get in touch.
- Nussbaum, E.L. (1997). Ultrasound: To heat or not to heat-that is the question. Physical Therapy Review, 2, 59-72.
- Watson, T. (2008). Ultrasound in contemporary physiotherapy practice. Ultrasonics, 48, 321-329.
- Dyson, M. (1987). Mechanisms involved in therapeutic ultrasound. Physiotherapy, 73(3), 116-120.
- Heckman et al. (1994). Acceleration of tibial fracture0healing by non-invasive, low intensity, pulsed ultrasound. The journal of Bone and Joint Surgery Am, 76:26-34.