The sacral curve consists of how many fused vertebrae?

The sacral curve is formed by the fusion of five vertebrae, which create the sacrum. In human anatomy, the sacrum is a triangular bone situated at the base of the spine, and it plays a critical role in connecting the spine to the pelvis. This fusion of vertebrae occurs during adolescence and results in a single, solid structure that contributes to the stability of the pelvic region. The five fused vertebrae also help to support weight and facilitate movement between the spine and the lower limbs. Understanding the structure of the sacral curve is essential for recognizing its function in biomechanics and posture during activities such as Pilates, where core stability and spinal alignment are fundamental.