We retrospectively reviewed 183 children with a simple fracture of the distal radius, with or without fracture of the ulna, treated by closed reduction and cast immobilisation. The fracture redisplaced after an initial, acceptable closed reduction in 46 (25%). Complete initial displacement was identified as the most important factor leading to redisplacement. Other contributing factors were the presence of an ipsilateral distal ulnar fracture, and the reduction of completely displaced fractures under deep sedation or local haematoma block. We recommend that completely displaced fractures of the distal radius in children should be reduced under general anaesthesia, and fixed by primary percutaneous Kirschner wires even when a satisfactory closed reduction has been achieved.