Functional scoliosis: A structurally normal spine that appears to have a lateral curve (scoliosis).
Nonstructural scoliosis involves a temporary change of spinal curvature. This is caused by an underlying condition such as a difference in leg length, muscle spasms, or inflammatory conditions, (e.g. appendicitis), which may produce muscle spasm. Functional scoliosis is treated by correcting the underlying problem. The spine itself needs no treatment.
Functional scoliosis is also called nonstructural scoliosis as opposed to structural scoliosis in which there is a fixed curve of the bones of the spine (the vertebrae).