Which sequence correctly describes the order of involvement in adult spondylodiscitis?

• A. Anterior vertebral endplate followed by osseous destruction of the vertebral body
• B. Intervertebral disc first
• C. Posterior elements
• D. Spinous processes

Answer: (A)

In adult pyogenic spondylodiscitis, the infection typically seeds the spine through the blood and first targets the anterior vertebral endplates. The endplates are where the inflammation begins, so imaging and pathology show endplate involvement early. From there, the infection spreads into the adjacent vertebral body, causing osseous destruction. The intervertebral disc is avascular, so it is not the initial site and tends to become involved only after the endplates and vertebral bodies are affected. Involvement of the posterior elements or spinous processes is not the usual early pattern in this condition. So the order described—anterior vertebral endplate first, followed by destruction of the vertebral body—best reflects the typical progression.