According to Fryette's laws of vertebral motion, which regions of the spine do they apply to?

Fryette's laws of vertebral motion specifically apply to the thoracic and lumbar regions of the spine. These laws describe the mechanics of spinal motion in these segments, particularly how vertebrae move in relation to one another in various planes of motion.

The first law states that in group motion, if the thoracic or lumbar spine is in neutral, side bending and rotation occur in opposite directions. The second law applies when the spine is in a non-neutral position (flexed or extended), indicating that side bending and rotation occur in the same direction. The third law states that motion in one plane affects motion in the others, meaning that if the spine is moved in one plane, the motion will affect its motion in the other planes.

These principles are primarily applicable to the thoracic and lumbar regions due to their functional anatomy and mechanical behavior, distinguishing them from the cervical spine, which has a different model of motion mechanics due to its unique structure and range of motion. The cervical spine exhibits a greater degree of flexibility and allows for distinct rotational and translational movements that do not conform strictly to Fryette's laws.

Thus, the correct understanding that Fryette's laws apply to the thoracic and lumbar spine allows clinicians to better assess and treat conditions linked