Which bone is the exterior bone of the forearm, descending from the elbow to the wrist?

Which bone is the exterior bone of the forearm, descending from the elbow to the wrist?

• A. Ulna
• B. Humerus
• C. Radius
• D. Scapula

Answer: (C)

The outside bone of the forearm that runs from the elbow to the wrist is the radius. In the anatomical position, it sits on the thumb side (lateral) of the forearm, making it the exterior bone as you travel from the elbow toward the wrist. The radius extends from the distal end of the humerus at the elbow down to the carpal bones of the wrist, and it plays a key role in forearm rotation because it crosses over the ulna when you turn the palm up or down. The other long bone in the forearm is the ulna, which is on the pinky side (medial) and not the exterior bone in this sense. The humerus is the upper arm bone, and the scapula is the shoulder blade.

The outside bone of the forearm that runs from the elbow to the wrist is the radius. In the anatomical position, it sits on the thumb side (lateral) of the forearm, making it the exterior bone as you travel from the elbow toward the wrist. The radius extends from the distal end of the humerus at the elbow down to the carpal bones of the wrist, and it plays a key role in forearm rotation because it crosses over the ulna when you turn the palm up or down. The other long bone in the forearm is the ulna, which is on the pinky side (medial) and not the exterior bone in this sense. The humerus is the upper arm bone, and the scapula is the shoulder blade.