West Coast EMT Block One Exam

Which part of the body is both the mechanical weight-bearing base of the spinal column and the fused central posterior section of the pelvic girdle?

1. coccyx.

2. ischium.

3. sacrum.

4. thorax.

The correct answer is: sacrum.

The sacrum serves as both the mechanical weight-bearing base of the spinal column and the fused central posterior section of the pelvic girdle. It is a triangular-shaped bone located at the lower end of the vertebral column and consists of five fused vertebrae. The sacrum connects the spine to the pelvis, providing crucial support during various activities such as walking, sitting, and lifting. In terms of its anatomical structure, the sacrum helps distribute body weight through the pelvis and to the lower extremities, making it essential for stability and mobility. Its fusion provides strength and rigidity to the pelvic girdle, reinforcing the body's overall structural integrity. The coccyx is also part of the vertebral column but serves as a small, terminal portion and is not involved in the mechanical weight-bearing function to the same degree as the sacrum. The ischium is one of the three components of the pelvic bone but does not serve as the weight-bearing base for the spinal column. The thorax refers to the chest region, which includes the ribs and sternum, and is not relevant to the question regarding the spinal column and pelvic girdle.