When the facet is stuck in extension, which movement is restricted?

When the facet is stuck in extension, which movement is restricted?

• A. Flexion
• B. Extension
• C. Ipsilateral rotation
• D. Ipsilateral side flexion

Answer: (A)

Moving toward flexion is restricted when a facet joint is stuck in extension. The facet joints guide and limit spinal motion by their orientation and contact surfaces. When a facet is in extension, the joint surfaces are already pressed together, closing the posterior joint space. Flexion, which would require the facets to separate and slide to allow the spine to bend forward, is therefore hindered. In contrast, extension isn’t restricted because the spine is already in that position, and the other movements (like rotation or side bending) may be variably affected but are not the direct consequence of a facet held in extension.

Moving toward flexion is restricted when a facet joint is stuck in extension. The facet joints guide and limit spinal motion by their orientation and contact surfaces. When a facet is in extension, the joint surfaces are already pressed together, closing the posterior joint space. Flexion, which would require the facets to separate and slide to allow the spine to bend forward, is therefore hindered. In contrast, extension isn’t restricted because the spine is already in that position, and the other movements (like rotation or side bending) may be variably affected but are not the direct consequence of a facet held in extension.