Which bone in the forearm is located on the same side as the thumb?

The radius is the bone in the forearm that is located on the same side as the thumb. In human anatomy, the forearm consists of two main bones: the radius and the ulna. The radius is situated laterally (on the thumb side) when the body is in the standard anatomical position, which is standing upright with palms facing forward. This positioning illustrates that the thumb points outward, thereby aligning with the radius.

The ulna, on the other hand, is positioned medially (on the side opposite to the thumb). The carpals are wrist bones and do not contribute directly to the thumb's positioning. The tibia is not relevant in this context, as it is located in the lower leg and does not pertain to the bones of the forearm. Therefore, understanding the relative positioning of the radius and ulna is essential for identifying which bone aligns with the thumb.