Ultrasound is an oscillating sound pressure wave with a frequency greater than the upper limit of the human healing range. Ultrasound is thus not separated from ‘normal’ (audible) sound based on differences in physical properties, only the fact that humans cannot hear it.
Ultrasound was first developed as a diagnostic tool in Glasgow in the 1950s. Orthopaedic surgeon Angus MacLean has been using the ultrasound technology at Glasgow’s Royal Infirmary’s fracture clinic.
It has been shown to speed up recovery times for patients with severe fractures by more than a third. It is used for difficult fractures, the ones with problems with healing, and it’s a very simple, painless treatment that we can give. It’s an interesting scientific development and there’s good evidence that it just vibrates the cells a little which then stimulates healing and regeneration in the bone.
A team of specialists, led by Professor Ian Donald, produced the first images of the body using a technology adapted from sonar at Glasgow’s Western Infirmary.
It has become one of the most common medical technologies in the world. It is only now, 50 years later, that its potential for aiding the healing process is being unlocked.
Apprentice engineer Gary Denham was offered ultrasound treatment after he fell 20ft (6m) from a water tank and broke his ankle into eight pieces. “It’s got a wee strap and that goes round where the break was,” he explained.
“I put some gel on the probe and then I just put the probe inside the strap and then just basically leave it for 20 minutes. There’s no sensation at all, it’s completely painless.”
Mr Denham’s injury was so severe that there was a chance it would never heal and might eventually have to be amputated. After ultrasound treatment, he was back on his feet within months.
He added: “I’d never heard of it before, but my leg healed after four months and I’m looking to go back to work within eight months.”
Because of the costs involved – around £1,000 per patient – ultrasound is only being used on complex fractures at Glasgow Royal Infirmary but Mr Denham’s doctor, Mr MacLean, is very happy with the results. “Before we used ultrasound I would expect to see this kind of injury healing with some difficulty, and some of them don’t heal at all,” he said. Even if they do heal, it can take between six and 12 months and patients have ongoing pain during that time.
“The evidence suggests that ultrasound speeds things up by about 40%, but the main interest for me is to use it to make sure the bone heals rather than the bone not ‘knitting’ together which then leads to serious problems.”
It is expected that the cost of using ultrasound to treat fractures will reduce over time, making it more economical to speed up the healing of common fractures as well as complex ones.