Osteopathic manipulation, or HVT (high-velocity thrust) as it is more technically known, is the “click” that many people associate with osteopathic treatment.
It is by no means always used by an osteopath, but when it is, it can prove to be a quick, efficient, and pain-free way of restoring function to a joint.
Many patients’ conditions may not be suitable for HVT, and many may not be keen to have it done anyway. In these cases, the osteopath will treat with a whole collection of other highly effective ways. HVT should be seen as a useful tool in some circumstances, but not a be-all and end-all of osteopathy.
So how does it work?
HVT is placing a short sharp tug though a joint, most often a spinal facet (which is what we will concentrate on here), a click may or may not be heard. The noise itself is a bit of a by-product. What it is has been disputed a little but the generally accepted explanation is that when the joint is stretched, the synovial fluid inside the joint itself physically does not stretch, so gas is forced out of solution causing gas bubbles that allow the joint to gap slightly, causing the clicking noise. This also explains why another click cannot be produced for a little while until the gas has been reabsorbed.
The gapping of the joint is the key to the effectiveness of HVT.
What I must point out at this point though is that the click is not a relocation of a joint.
Barely a day goes past that someone doesn’t tell me their osteopath “clicked something back in” often assuming it was a disc. As much as it can feel miraculous like this sometimes, and a patient can often feel and be quite a bit straighter following treatment, the HVT is about restoring function to the joint, not putting it back in place. Discs especially do not just “pop back in”.
So what does the gapping achieve?
Well, here we have to get a little technical. There are three predominant effects caused by HVT as far as we can tell.
Firstly, post-contractile sensory discharge or PCSD.
Imagine that the brain keeps many muscles at a gentle tension, this allows you to hold your posture. When an area is identified as problematic (painful or inflamed etc), the brain may choose to cause the muscles around the area to spasm, often to protect the area. The spasm itself may cause further pain. This then becomes a vicious circle and dysfunction.
Tension in the muscles is controlled by spindle fibres. This is what detects the short sharp tug of the muscles in HVT. Imagine the short sharp tug as a reset for these fibres. The brain then has to determine the level of muscle tension required and often can reset to the original tension, immediately bringing the joint out of spasm.
Massage of muscles, slow stretching over a longer period, has a similar effect but unfortunately can’t be performed on the small, deep muscles directly around and holding the joint.
Secondly, pain gate theory.
Even when nerves are reporting pain in a certain area, it is important that the body can still detect a soft touch in the same area. To achieve this soft touch and position detecting nerves override deep pain detecting ones. Where you ever told to rub your knee or elbow after you bumped it and it hurt? That’s pain gate, the soft-touch overrides the deep pain. It won’t stop it completely of course but even a little relief will make it feel better. In turn, this may again stop the brain causing the area to spasm.
HVT moves the joint quickly and sharply. This causes the positional detectors to immediately report this to the brain, inhibiting the deep pain.
Thirdly, meniscoid theory.
In a joint, smooth cartilaginous surfaces rub together, but they may not be quite as smooth as we used to think. Small pieces of cartilage appear to be in the joint. Possibly to fill small gaps; craters on a moonscape is a good way to think of it. It has been suggested that when the joint spasms, these small bits of cartilage, which are attached to the capsule around the joint can become trapped out of place. Gapping the joint allows the tethers to the capsule to quickly pull them back into place.
It’s possibly worth pointing out before I finish, that although I said earlier that the click is an unnecessary by-product, I do wonder if it could be argued that the psychological effect of hearing the click could be put forward as a fourth effect. Hearing a click and knowing that it may have relieved a painful joint does often make a patient immediately relax. This may itself be part of the healing process.
Osteopathic manipulation is often a quick efficient way of relieving dysfunction of a joint. It is not a miracle cure. Many other things have to be taken into account for the osteopath to treat fully and effectively.
HVT will not immediately heal damaged tissue or disperse inflammation, but it often is a good way to kick start the process.
By Andrew Doody | Osteopath | August 2019