radius: Quick Facts

Written and fact-checked by

The Information Architects of Encyclopaedia Britannica

Photos

Anterior view illustration of the right radius and ulna arm bones in supination, with labeled anatomical features including the head of radius, olecranon process, trochlear notch, and styloid processes.

Anterior anatomical illustration of the human elbow joint showing the humerus, ulna, and radius bones, with labels for the trochlea, trochlear notch, and annular ligament.

Anterior view illustration comparing the bones of the human forearm (radius and ulna) on the left and the lower leg (tibia and fibula) on the right, with major anatomical features labeled.

Diagram comparing the forelimb bone structures of a human, horse, dolphin, box turtle, fruit bat, and chicken, with color-coded bones showing homologous parts to illustrate evolutionary relationships.

See All Images and Interactives →

Topics

radial tuberosity interosseous border styloid process arm forearm bone vertebral column hyoid bone ear bone rib ulna skull sternum femur fibula humerus

Superficial arteries and veins of face and scalp, cardiovascular system, human anatomy, (Netter replacement project - SSC)

The Human Body

Muscles of facial expression, human anatomy, (Netter replacement project - SSC). Human face, human head.

Characteristics of the Human Body

Bones of the wrist and hand: dorsal view. skeletal system, human anatomy, appendage, hand bones, wrist bones, metacarpal bones, finger bones, phalanges.

Human Bones Quiz

full human skeleton

The Skeletal Puzzle