Differences between the Overt and Chronic Instability and the Reflection of These Differences in the Treatment

White and Panjabi (1) defined the concept of “clinical stability” as the ability of spine to limit the deformation examples to prevent damaging and irritation of the spinal cord and nerve roots by the spine under physiological loads and to prevent pain arising from deformation or structural changes. Spinal stability responds differently to various forms of physiological loading and provides the spine with support in variable levels depending on the condition. Therefore, spinal stability must be defined also depending on the condition. Although defining the stability is difficult, evaluation of instability is less so.