Radius

Definition

The radius is one of the two long bones in the forearm, located on the lateral side (thumb side) when in the standard anatomical position. It plays a crucial role in wrist and elbow movements by articulating with the humerus, ulna, and carpal bones.

5 Must Know Facts For Your Next Test

1. The radius is shorter than the ulna but thicker and stronger.
2. It articulates with the humerus at the elbow joint and with carpal bones at the wrist joint.
3. The radial tuberosity serves as an attachment point for biceps brachii muscle.
4. The distal end of the radius features a styloid process that helps stabilize the wrist.
5. Fractures of the radius, especially near the wrist (Colles' fractures), are common injuries.

Review Questions

• What muscles attach to the radial tuberosity?
• Where is the radius located in relation to the ulna?
• What type of fracture commonly occurs at the distal end of the radius?

Related terms

ulna:

One of two long bones in the forearm, located on the medial side opposite to the radius.

humerus:

The single bone of the upper arm that connects with both radius and ulna at its distal end.

carpals: A group of eight small bones that form part of the wrist joint by articulating with both ends of radius and ulna.