Joint stability refers to the resistance offered by various musculoskeletal tissues that surround a skeletal joint. Several subsystems ensure the stability of a joint. These are the passive, active and neural subsystems.[1] It is believed that one or more of the subsystems must have failed if joint instability occurs, usually a torn or overstretched ligament. Instability of joints can cause unhealthy ranges of movement in your joints, which can result in the joints fracturing.[citation needed]
The bony components that may relate to the potential for joint instability can be measured by use of x-rays. Plain film lateral x-rays can be used to evaluate for translations anteriorly (anterolisthesis) or posteriorly (retrolisthesis). Where plain films indicate the likelihood of these translations being significant, flexion-extension views can be utilized to determine the dynamic range of movement of joints. This allows for a more accurate view of any potential instability issues.[2]