Introduction and objectives: The most commonly used treatment for extraarticular fractures of distal radius is closed reduction and maintenance of reduction in a cast. Two types of casts are used: plaster splint for 7–10 days and later exchanged to a circular cast and the use of circular cast immediately. The objective of this work is to compare both types of treatment in terms of ability to achieve reduction and to maintain it during healing.

Methods: A prospective, randomized and blinded study was designed. To date, 21 patients enrolled the study. Informed consent was given. The inclusion criteria were: older than 35 years, extraarticular distal radius fracture sustained less than 24 hours before and not previously treated. Exclusion criteria included previous injury in the same wrist, open fracture, and not compliance with the protocol. After intrafocal anesthesia with mepivacaine 1%, fracture was reduced under traction and immobilized in a dorsal short plaster splint (splint group) or a circular short plaster cast (circular group) randomly. After 10 days of immobilization, the plaster splint was changed to a circular short plaster cast. AP and lateral X-Rays were taken before reduction, after reduction, after 10 days (before changing cast), and at 21 days. Volar inclination of lunate fossa on the lateral X-Ray was obtained. On the AP proyection, the radial inclination and radial length was measured. Complications were recorded. Data was analysed through ANOVA between groups.

Results: When comparing X-rays before and after reduction, the volar inclination of the lunate fossa on lateral projection changed from −21,4° to 8,60° (30° change) after reduction in splint group and from −15,22° to 1,78° (17° change) in circular group (p< 0.05). The other comparisons were N.S. When comparing after reduction and 10 days later, the radial inclination changed from 20,20° to 18,80° (1,40° change) in the splint group and from 20,89° to 20,44 (0,44° change) in the circular group (p< 0.05). Other comparisons were N.S. No differences were found between 10 days and 21 days in any X-Ray parameter. No complications were found.

Conclusions: A better reduction was achieved with the plaster splint method in the immediate X-Ray control. Nevertheless, reduction was better maintained during the first 10 days with the circular plaster cast method.