What is the shape of the structure referred to as the manubrium?

The manubrium is a part of the sternum, which is the bone located in the center of the chest that connects to the ribs. The shape of the manubrium is described as handle-shaped, resembling the handle of a sword or an umbrella. This unique shape allows for articulation with other structures, specifically the clavicles (collarbones) and the first two pairs of ribs, facilitating the expansion of the ribcage during breathing. The handle-like configuration is essential for its functional role in the thoracic skeleton, providing support and stability while also allowing for movement. Additionally, other shapes like square, round, or triangular do not accurately describe the manubrium's geometry, underscoring why the handle-shaped description is appropriate.