A Colles Fracture is a complete fracture of the radius bone of the forearm close to the wrist resulting in an upward (posterior) displacement of the radius and obvious deformity. Colles' fractures most often occur with a fall onto an outstretched hand. The fall sends force through the bones and displaces the distal radius toward the back of the hand or forearm. Doctors can treat most Colles' fractures with casting or splinting.