Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
A primary curve refers to the spinal curvatures present at birth, which are convex posteriorly and include the thoracic and sacrococcygeal (pelvic) curves. These curves are essential for distributing mechanical stress during movement.
Related terms
Thoracic Curve: The thoracic curve is part of the primary curvature of the spine, characterized by a convex shape posteriorly, supporting the chest and upper back.
Sacrococcygeal Curve: This curve forms the bottom part of the spine's primary curvature, contributing to pelvic stability and weight distribution while sitting.
Secondary Curve: Secondary curves are spinal curvatures that develop after birth, including the cervical and lumbar curves, which are convex anteriorly and aid in human posture and movement