What's The Crack? Manipulation explained
Are you familiar with videos that circulate social media showing someone ‘cracking” joints or the spine? But what makes that satisfying sound and what does it achieve? In this blog, I will explain what manipulation is, how and why it is done and briefly explore the other possible causes of back cracking. Contrary to the old wives’ tale, there is no evidence to suggest that this technique can cause arthritis. Another outdated belief is that the click is produced by bone rubbing on bone. Again, this is not correct.
Osteopaths, Physiotherapists and also Chiropractors can use this technique for treating neck and back pain. Manipulation is often also associated with an audible ‘crack’ or ‘click’ (which often feels very satisfying) and can be applied to various joints in the body. As an osteopath myself, I do use joint manipulation as part of my treatments but I only perform them on people who one – would actually benefit from it (as not everybody needs manipulation) and two – only with other techniques to maximise the effectiveness of the treatment.
In order to understand how a manipulation works, a basic understanding of spinal anatomy is required. The spine is made up of blocks called vertebrae which are stacked on top of each other like a tall tower. Each vertebrae is separated from each other by a spinal disc that sits in between each one. Each vertebrae has two facet joints attached to it, one on the left and one on the right. The facet joints of one vertebrae connect with the facet joints on the vertebrae above and with the facet joints on the vertebrae below so that each vertebrae are in contact with each o
ther. These facet joints are strengthened by ligaments and muscles and are surrounded by a little joint capsule. Fluid known as synovial fluid sits within the joint capsule and its role is to lubricate the joint so that the facet joints can move smoothly without getting stuck on each other. During an osteopathic manipulation, it is the movement of these facet joints that causes the audible ‘pop’ or ‘crack’ you can hear.
During the manipulation
During the manipulation, the osteopath will focus a little pressure onto the appropriate facet joint. The manipulation may involve a little twist or thrust movement. During the thrust, the air pressure in the facet joint is suddenly altered. When this happens, gas escapes from the joint and produces a ‘pop’ or ‘crack’ sound. This shouldn’t be painful. When air pressure has changed in the joint, it takes around 20 minutes for the joint to regain normal air pressure again. During this period you will not be able to manipulate the joint again. (That’s why when you crack your knuckles, you have to wait for a little bit before you can do it again).
What Can Manipulation Achieve?
Stop the swelling of a joint capsule.
Reduce muscle tension.
Release endorphins (modulate inflammatory processes, promoting analgesia).
Increase the range of movement.
Relieve back pain.
Other causes of cracking spinal joints
It is possible to experience an involuntary crack from time to time. If the cause is not attributed to a direct manipulation, other likely causes are:
Ligament or tendon snapping – this is completely normal and involves surrounding ligaments and tendons flicking over each other or other bits of bone as they move. (This is also very common in the hips and knees).
Bone grinding – as we get older, the spine may start showing signs of wear and tear. This is a normal part of ageing. As the cartilage in the spine starts to break down, it provides less protection and cushioning for the bones of the spine and as a result they can start rubbing on each other which can create a ‘crack’, ‘pop’ or ‘grinding’ sound.
Is manipulation safe?
Whilst the long term benefits of back cracking is not known, it has shown to provide short term temporary relief for certain types of back and neck pain. That said, not all types of back and neck pain are suitable for manipulation. Other factors such as age, certain conditions or lifestyle habits may also mean that manipulation isn’t appropriate. Further research is required to fully understand the long term implications. This is also another reason why having your back or neck cracked should only be done when necessary. Other osteopathic techniques should be used alongside manipulation and advice on certain exercises and stretches should also be used as part of the treatment plan.
If you are concerned about your own back or neck, or you have any questions, feel free to get in touch!