September 11th 2015 | Physiotherapy
What is it?
There are many different types of joint and each is designed to move in a particular way. Some joints move in one direction (for example a hinge joint like the knee or elbow), and other joints move in many different directions (for example a ball and socket joint like the shoulder or hip).
In basic terms, a joint is where bones meet. Muscles make the bones, and therefore the joints move. A joint has bone ends which are covered in cartilage to protect them, a joint capsule (like a sack that holds everything together), ligaments to strengthen the joint capsule and then muscles and tendons close by to make it move. Any of these structures can send pain signals to the brain. Some joints are more complex than this but there are similarities in most joints in the body.
Joints are designed to have a normal available range of motion; the maximum amount of movement they can cope with before something is damaged. When something moves beyond this range of motion then it will cause pain. It has previously been shown for example in the spine during a forward bending movement that the posterior elements – including joint capsule, ligaments and intervertebral disks are under a lot of strain. If the movement happens too quickly, with too much force or for too long, one of these structures is likely to be damaged and therefore painful.
The axis of rotation of a joint is the pivot point or the central part of the movement. In the hip or shoulder the axis is through the centre of the joint and the joint effectively spins around that axis.
When the axis of rotation is changed, it places different parts of the joint under more strain.
Remember that muscles cause joints to move. Tight muscles on one side of the joint and weak muscles on the other side of the joint can change that axis of movement.
In the early stages that will cause the joint capsule and possibly ligaments to send warning signals to the brain. If this goes on for long enough, it will cause wear and tear to parts of the joint. Joint wear and tear is technically called osteoarthritis. Similarly, tight muscles can cause joint compression (squashing a joint together). A joint that is more compressed is again more susceptible to osteoarthritis.
Joint pain is usually well localised to a particular area. The symptoms do not radiate that far away from the joint. Pain is sometimes described as being deep (although this depends on the structure of the joint in question). Joints may be noisy. This can include a grinding type noise, clicking and cracking. Join ts that have become a bit worn out are often stiffer in the mornings or after periods of not moving and prefer to keep moving to keep them mobile.
What can cause this?
Postural dysfunctions can cause some joints to be compressed. The same postural dysfunction will cause muscles to adapt to a shortened position which will change how the joint moves. When these muscles start to be stiffer or tighter, movement throughout the whole body will change which can then affect other joints as well.
There are different muscles that help to control joints. There are deep stabilising muscles and bigger mobiliser muscles. If the deeper stabilising muscles are not doing their jobs properly (core weakness or lack of core control) then the bigger ones take over. As the bigger muscles are not designed to do this, they often get tight and sore. Deep stabilising muscles can become inefficient in cases of pain, trauma, surgery and postural dysfunction. As described above osteoarthritis potentially happens in different stages: something is not moving properly and some muscles become tight; the joint starts to send warning signals to the brain; the joint starts to get damaged and then in later stage osteoarthritis the joint is totally worn out and bone is effectively rubbing on bone with no protection.
If you think that you might have a Tendinopathy or want some advice on why it has happened and how to fix it, then call us on 01595 692727 or email on firstname.lastname@example.org