Updated: Jul 14
High Volume Injections as treatment for Achilles tendinopathy (this article)
A high volume injection is one of the treatment options for patients with mid-portion Achilles tendinopathy. In this article, I take a look at how this injection is thought to work and whether this is backed up by research.
In this article:
How are high volume injections thought to work?
They inject a high volume of normal saline (sterile water) into the tendon. It should be done under ultrasound guidance so that they can target the injured part of the tendon. They also inject a small amount of anaesthetic so that the injection isn’t painful. Sometimes they also include a small amount of corticosteroid.
The main objective with a high volume injection is to decrease pain. It is mostly used for patients whose pain levels are preventing them from progressing with their rehab exercises. Remember, pain is not an indicator of the severity of an injury, so it is OK to use adjunct treatments to decrease your pain and allow you to get on with the rehab that will make your tendon strong again.
A high volume injection is not a standalone “cure” for Achilles tendinopathy, and it's usually used in conjunction with a progressive rehab programme. When you have Achilles tendinopathy, you lose some of the strength in your tendon, so the rehab programme is important because it’s the only way to get your tendon back to its pre-injury strength. If you jump back into full sport without doing your rehab first, you’ll likely just flare your pain up again.
What does the research say – do they actually work?
There’s really not a lot of high quality research available yet, but the current studies do seem to suggest that high volume injections can be useful when combined with a structured rehab programme.
We’re not sure how exactly these injections manage to decrease the pain. One theory is that the high volume of fluid and the movement of the needle has a mechanical effect on the tendon and that also collapses the small blood vessels that usually grow into the injured part of a tendon. These blood vessels aren’t found in healthy tendons. Each blood vessel has a little nerve that grows with it and these nerves are thought to cause some of the pain when you have a tendinopathy. When the blood vessels collapse, it also gets rid of the little nerves which is then thought to be the reason why your pain decreases.
We know that corticosteroid is a very good pain killer in the short term, so another school of thought is that it’s actually the steroids that is behind the drop in pain. However, there are studies that have shown that high volume injections can be effective even if the corticosteroid is left out.
Nobody has so far investigated the effect that the anaesthetic has on how well these injections work. We know that the pain created by ongoing injuries can become disproportionately high, and it may very well be that the anaesthetic just resets the pain system back to normal.
If you’re struggling to progress with your rehab and your pain levels remain high despite doing all the right things, having a high volume injection may be a treatment option worth considering.
How we can help
Need more help with your Achilles injury? You’re welcome to consult one of the team at TMA online via video call for an assessment of your injury and a tailored treatment plan.
We're all UK Chartered Physiotherapists with Master’s Degrees related to Sports & Exercise Medicine. But at Treat My Achilles we don't just value qualifications; all of us also have a wealth of experience working with athletes across a broad variety of sports, ranging from recreationally active people to professional athletes. You can meet the team here.
About the Author
Boesen, A. P., et al. (2017). "Effect of high-volume injection, platelet-rich plasma, and sham treatment in chronic midportion Achilles tendinopathy: a randomized double-blinded prospective study." The American Journal of Sports Medicine 45(9): 2034-2043.
Boesen, A. P., et al. (2019). "High volume injection with and without corticosteroid in chronic midportion achilles tendinopathy." Scandinavian Journal of Medicine & Science in Sports 29(8): 1223-1231.