Lesson 1.5: Movement Dysfunction

1. Neurological Dysfunction

2. Soft Tissue Dysfunction

3. Systemic Inflammatory Process

4. Osteoarthritic Dysfunction

5. Mechanical Joint Dysfunction

(I will define the seperate movement dysfunctions in Chapter 2. You will learn how to differentiate the 5 movement dysfunctions in Chapter 3 and how to fix a mechanical joint dysfunction in Chapter 5.)

During mechanical joint dysfunction, there are three locking mechanism that will decrease passive and active movement. There is an arthro-mechanical locking locally at the joint level. Myo-mechanical locking results as a co-contraction of the muscles above and below the affected joint to stabilize and protect it from painful movement. There is also a peripheral-mechanical locking resulting in compromised movement at the joints above and below the primary joint restriction. This is due to movement changes above and below the primary joint dysfunction and results in the kinetic chain effect where an entire chain of joints are not able to move through their full range of motion.

There are three precipitating factors that result in mechanical joint dysfunction and related irritation: repetition, systemic issues, and trauma. 

Repetitive motion puts a person at risk for mechanical joint dysfunction. The joint is most vulnerable to dysfunction in the position of greatest movement, which is flexion. Normal asymmetry of the skeleton increases this mechanical vulnerability. The joints form differently from one side to another during normal development.  Most individuals are asymmetrical right to left.  Adoption of the upright posture is one of the causes of back pain. As we evolved, humans went from walking on all fours to walking on two feet. In the upright position, gravity pushes the skeleton down into flexion causing mechanical vulnerability.

Sitting is an act of repetition. A person who leads a sedentary lifestyle exhibits structural adaptive changes over the course of many years. Bed rest also results in joint immobility and decreased tissue pliability. This in turn gives rise to mechanical vulnerability along with significant effects on bone and tissue health.

A specific incident or trauma can cause mechanical joint dysfunction. A relatively minor traumatic insult to a joint capsule results in an excess of normal synovial fluid, or swelling.  This can lead to sensory receptor activity and motor disturbances, which then results in mechanical joint dysfunction and pain. If there is neural tissue damage this can also lead to an altered arthrokinetic reflex and mechanical dysfunction. Nerve tissue damage is inevitable with joint surgery and will result in a disturbance of the arthokinetic reflex and therefore mechanical joint dysfunction.

 A medical condition can make one vulnerable to mechanical joint dysfunction. Neuromuscular conditions such as a stroke can cause muscle weakness or pain and result in loss of joint motion. A congenital anomaly can cause asymmetrical movement patterns and make one susceptible to mechanical joint dysfunction. Degeneration, such as arthritic changes of an aging joint, can also make a person vulnerable. Endocrine changes, metabolic changes and infections can change tissue extensibility and mechanical patterns as well.