What’s the difference between scoliosis and a spinal fusion?

A friend asked me what’s the difference between scoliosis and a spinal fusion. She thought that the fusion was something present at birth. There is a bone disorder in which two or more bones of the cervical vertebrae have fused together. However, a spinal fusion due to severe scoliosis is a surgery that permanently connects two or more vertebrae and eliminates your motion between them. The goal of the surgery is to stop the progression of the sideways curvature of the spine, provide stability, and hopefully reduce pain in some cases. Besides scoliosis, there are numerous other conditions which may lead to a spinal fusion, and these tend to be shorter fusions.

Pictured here is my spine after spinal fusion, and Harrington rods were used to provide stability for my new spine as it fused.