In whiplash-related intervertebral disc injury, annular tears involve which part of the disc?

• A. Inner nucleus
• B. Outer layers
• C. Endplates
• D. Vertebral body

Answer: (B)

Annular tears are fissures in the annulus fibrosus, the tough outer ring of the intervertebral disc. In whiplash, the rapid flexion–extension and shear forces stress the disc, and the outer layers bear the brunt of that tensile loading, so tears occur in the outer portion of the annulus. The nucleus pulposus lies at the center and remains largely intact initially, endplates and vertebral bodies are separate structures at the disc’s interfaces rather than the site of the tear. So, the part involved by annular tears is the outer layers of the disc’s fibrous ring.