Joints

Joint-brain axis

Joints are driven by the brain since joint disorders are influenced by all factors of the nervous system.

The nervous system controls key aspects of joint problems by regulating joint position, muscle and tendon length, the stress axis, metabolism, and inflammation. All these factors and more can influence how a joint functions. Therefore, joint stability is achieved by not only addressing the joint itself, but also other systems that support its position.

Joints also provide important information to the brain about where the body is in space. This is called joint position sense. Information from joints of the neck, for example, play an important role in head-on-body orientation. The joints communicate information to the visual and balance (vestibular) centres in the brain and brainstem and maintain posture.

Central nervous system sensitivity

Joints can be a major source of pain. Mechanical aggravation of a joint can lead to ongoing pain signals in the nervous system because of the many pain receptors found in a joint. Chemicals are also released in and around a joint that can increase pain and inflammation. Over time, ongoing pain signals can cause nerves to become sensitive and lead to more pain signals within the spinal cord and brain. Sometimes, the brain and brainstem is also not able to control these pain signals very well and a chronic pain condition manifests.

Well-working joints and good joint-brain communication is important for preventing musculoskeletal injuries by telling the brain to avoid excessive movements. Injuries and ongoing pain can arise when the joint-brain axis is disrupted through misalignment, inflammation or stress.