Which statement about the thoracic spine's Fryette's principles is accurate?

• A. Only Type I dysfunction occurs in the thoracic spine.
• B. Only Type II dysfunction occurs in the thoracic spine.
• C. Both Type I and Type II dysfunctions can occur in the thoracic spine.
• D. Fryette's principles do not apply to the thoracic spine.

Answer: (C)

In the thoracic spine, you can see both Fryette Type I and Type II patterns. Type I occurs when multiple vertebrae move as a group in a neutral position, with rotation and side-bending happening in opposite directions. This group pattern fits well with the thoracic region’s constraints from the rib cage, so you often see a cluster of segments rotating one way while side-bending the other way.

Type II appears when a single thoracic segment is non-neutral (flexed or extended). In that situation, rotation and side-bending occur to the same side for that segment.

Fryette’s principles describe how motion couples across the spine, and they apply to the thoracic region just as they do elsewhere. The idea that only one type occurs or that these principles don’t apply to the thoracic spine isn’t accurate.