Osteopathy is a very broad discipline within manual medicine that uses a lot of different techniques to treat our patients. This diversity within our treatment “tool kit”, so to speak, is what gives us the ability to adapt and tailor our treatment approach to each individual that walks into the treatment room. Each technique has its own mechanism, benefits and risks associated with it, all of which you should be aware of before undergoing treatment.
Of all the techniques manual therapists employ, likely the most polarizing is manipulation or “HVLA”. There is a great deal of stigma around this technique, both positive and negative, so I’d like to try and unpack exactly what it is, how it works, why we do it and the risks associated with it.
What is Manipulation?
Manipulation, put quite simply, is the passive movement of a joint. It can be broken down into 2 types being high velocity techniques (usually termed HVLA) and low velocity techniques (usually termed articulation). HVLA is the technique associated with the “pop” sound when it is performed and the technique that I will be focussing on. HVLA is used by all kinds of different manual therapists including Osteopaths, Physiotherapists and Chiropractors and even predates manual therapy itself! The early recorded evidence of HVLA we have is from 400 BC in Ancient Greece.
The technique is performed by placing a specific amount of “loading” or tension through the joint. Loading is what makes the technique more specific to a certain joint and safer overall as, the more specific the loading, the less force required to get the pop. The second part of the technique is where the “pop” or, more correctly, cavitation, takes place in the form of a high velocity, low amplitude (HVLA) thrust.
How does it work?
The goal of HVLA is to achieve cavitation of a particular joint, usually a stiff or sore one. The majority of joints in our body are filled with fluid which, when placed under specific tension undergoes a process called cavitation where we get the rapid formation of a gas bubble within the joint. This is what causes the “pop”.
The formation of the gas bubble decreases pressure within the joint allowing for increased range of motion which helps to decrease pain. The changes that occur within a joint are temporary which means HVLA is at its most effective when coupled with other techniques or with exercises and movement based activities.
Some old theories around HVLA were that we are moving joints or bones around or “putting joints back in”. This is no longer the accepted understanding of the technique. Nothing is moving or being “realigned” which is backed up by recent evidence of HVLA done under live MRI scans. Here’s a great video of a knuckle being manipulated!
Why do we do it?
HVLA provides a great short term window to see greater long term change. The decrease in pain and increase in movement it creates in joints allows for greater overall function. Greater function emphasises more efficient movement which is great for long term improvement of pain and discomfort. However as mentioned previously, HVLA is at it best when coupled with other techniques. Ultimately its greatest use is to create a window for you to move through life!
Side-effects and risks?
Every technique or intervention has its own risks associated with it and HVLA is no exception. Manual therapy and HVLA by extension doesn’t come in a box with the side effects printed in fine print on the back, this is why in your first appointment you will read through a consent form and your practitioner will have a discussion with you about the risks involved with the technique.
The side-effects of HVLA are usually transient/short-term in nature so you may experience some tenderness in the area or a fatigue like sensation for 1 to 2 days after. This is relatively common but if you are concerned or unsure contact your manual therapist.
Larger risks associated with HVLA are actually rarely reported in the literature however, they can sometimes occur and are usually associated with underlying predisposing factors which is why we take such a thorough history during your first visit and continuing questioning during follow up appointments as well. These risks include fractures, vascular complications (more often associated with neck HVLA) or neurological complications (compression of nerves). Whilsts cases of these events have occurred they are, overall, extremely uncommon. Your practitioner is trained to weigh up the risks and benefits of treatment and to screen for certain factors that may make HVLA unsafe.
The final say always comes down to you, the patient. If you don’t feel comfortable with HVLA or any technique we may use, be sure to tell your practitioner. Even if you have given consent for a technique to be used at a prior appointment you can always change your mind. Some people find the technique uncomfortable in certain areas (such as the neck) which is completely fine as well.
Whilst HVLA is a great tool in our arsenal of techniques it is NOT compulsory to you getting better. There are always other treatment options and different avenues to explore. Make sure to ask your practitioner any questions you may have about HVLA or any other techniques if you are concerned or, if you are like me, just like knowing a little bit more about everything!