What is the term for forward slippage of one vertebra over another?

• A. Spondylolisthesis
• B. Scoliosis
• C. Kyphosis
• D. Lordosis

Answer: (A)

The forward slippage of one vertebra over the one beneath it is called spondylolisthesis. This term specifically describes the anterior displacement of a vertebral body relative to the vertebra below it, most commonly occurring at the L5–S1 level. It can result from defects in the pars interarticularis (spondylolysis) or from degenerative changes, and it may lead to nerve compression or back pain.

Scoliosis refers to a lateral (sideways) curvature of the spine, kyphosis to an excessive forward rounding of the upper back, and lordosis to an exaggerated inward curve in the lumbar (low back) region. None of these describe a vertebral body slipping forward, which is why spondylolisthesis is the correct term.