Which vertebral body region is most commonly affected in Pott disease?

Explanation

## Anatomical Site of Pott Disease **Key Point:** Pott disease (spinal tuberculosis) characteristically affects the **anterior vertebral body and the adjacent intervertebral disc**, distinguishing it from pyogenic infections which typically spare the disc initially. ### Pathophysiology 1. Infection spreads via **Batson's venous plexus** (valveless vertebral veins) 2. Lodges in the **rich vascular metaphyseal region** of the vertebral body 3. Spreads to adjacent vertebrae and disc space (unlike pyogenic spondylitis) 4. Leads to vertebral body collapse and kyphotic deformity ### Classic Features - **Anterior vertebral body involvement** (90% of cases) - **Disc space involvement** (early and characteristic) - **Multiple contiguous vertebrae** affected (e.g., T12–L1) - Gradual destruction over months to years **Clinical Pearl:** The combination of anterior vertebral body destruction + disc involvement is pathognomonic for TB spine and helps differentiate from pyogenic spondylitis (which shows disc sparing initially) and metastatic disease (which is typically posterior). **High-Yield:** On imaging, look for the **"paradiscal" or "juxta-discal" sign** — TB affects the disc and adjacent vertebral bodies, creating a characteristic pattern that is a key diagnostic clue. [cite:Robbins 10e Ch 8]