The sacrum, which is a triangular-shaped bone located at the base of the spine, typically begins to fuse during adolescence and completes its fusion by the age of 30. The sacrum is made up of five individual vertebrae (S1 to S5) that start as separate bones but gradually fuse together to form a single, solid structure.
This fusion process is influenced by several factors, including genetics and hormonal changes. For many individuals, the fusion may start around the age of 16 to 18 years, and by the time one reaches their late twenties, the fusion is often complete. However, the exact timing can vary from person to person.
Understanding when the sacrum fuses is important for various medical fields, including orthopedics and pediatrics, as it helps in diagnosing conditions related to spinal development and alignment.